Drilling fluids containing an alkali metal formate

Abstract

A drilling fluid or mud is described wherein the drilling fluid contains at least one alkali metal formate or monovalent carboxylic acid salt. The drilling fluid preferably further contains at least one emulsifier or surfactant and at least one hydrocarbon-based fluid. The drilling fluids of the present invention can contain other conventional ingredients. The present invention permits drilling fluids to be essentially solids free due to the use of the alkali metal formate.

Description

BACKGROUND OF THE INVENTION

The present invention relates to the drilling industry and more particularly relates to drilling fluids used in drilling, such as the drilling of a well for the recovery of hydrocarbons or other materials.

In drilling operations, such as the drilling that occurs in oil field operations, drilling fluids are designed/formulated to serve several functions. These functions include acting as a lubricant to the drill bit to reduce wear and friction during drilling and also to seal the formation surface by forming a filter cake. Currently, in the industry, both oil-based muds (OBMs) and water based muds (WBMs) are typically used. More commonly, synthetic based muds (SBMs) are also used in drilling operations. In the drilling fluid, agents for lubrication are present as well as weighting materials in order to achieve a density that typically produces a pressure greater than the surrounding pressure in the well bore. Furthermore, the drilling fluid will also contain a sealing or fluid loss agent, such as calcium carbonate for pore bridging especially polysaccharides and other polymers, in order to form the filter cake on the formation surface of the well bore. In addition, when the drilling fluids are used during drilling, the drilling fluid will also contain drilling fines, such as shale and sandstone fines. During the drilling operations and afterwards, the filter cake seals the formation surface of the well bore so that the well bore can be completely formed without any leakage from the formation surface into the well bore and/or without any leakage of the drilling fluids into the formation surface. While the filter cake is beneficial for these reasons, once the drilling is completed, and the recovery of hydrocarbons is the next step, the filter cake can act as a severe impediment to the recovery of hydrocarbons. For instance, the filter cake can prevent the recovery of hydrocarbons from the formation surfaces which have been blocked or sealed by the filter cake. Furthermore, when injectors are used to retain reservoir pressures, the injection of sea water, for instance, can be significantly reduced due to the filter cake preventing the sea water from entering the formation and hence restricting the flow of water into the reservoir. Accordingly, the industry prefers to remove the filter cake from the well bore in order to optimize productivity. If the filter cake is not removed, the filter cake can block the pores that are part of the formation surface of the well bore which will interfere with the recovery of hydrocarbons. In many drilling operations, the drilling fluid can contain up to 5% by weight of a pore bridging material such as calcium carbonate. Calcium carbonate (CaCO3) is typically a blend of particle sizes with a particle size distribution designed to optimize the bridging of the pores found in the formation. The pore size distribution of the formation is determined from its permeability, preferably by direct porosity and permeability measurements of core plugs extracted from the reservoir.

Once drilling operations have been completed, the well is prepared for the completion operations whereby the mud used for drilling is often displaced by a completion fluid. Completion fluids are typically water based clear fluids and are formulated to the same density as the mud used to drill the well in order to retain the hydraulic pressure on the well bore. There are numerous methods of completing a well, amongst which are open hole completions and gravel packed screened systems. The clear fluids are typically halide based brines such as calcium bromide, calcium chloride, and zinc bromide; or organic based brines such as the formate based fluids.

In drilling an oil or gas well, the use of hydrocarbon-based drilling fluids are greatly preferred because of the inherent advantages of having an external phase fluid in contact with the formation. However, one severe disadvantage to a hydrocarbon-based drilling fluid is that weighting materials, such as barite, calcium carbonate, or hematite must be added to increase the density of the fluid. These weighting-material solids are capable of inducing formation damage to producing formations.

Thus, there is a need to provide hydrocarbon-based drilling fluids that are preferably solids free or have low solids in the contents in the drilling fluid in order to avoid the above-mentioned disadvantages.

SUMMARY OF THE PRESENT INVENTION

A feature of the present invention is to provide drilling fluids which are solids free or contain low amounts of solids in the drilling fluids.

Another feature of the present invention is to provide drilling fluids which are a hydrocarbon-water emulsion which are suitable for use as drilling fluids.

A further feature of the present invention is to provide drilling fluids which can have a variety of different densities in order to be useful in a variety of drilling situations depending on drilling depth and/or other variables.

Another feature of the present invention is to provide a more environmentally friendly drilling fluid that can be primarily aqueous based.

Additional features and advantages of the present invention will be set forth in part in the description that follows, and in part will be apparent from the description, or may be learned by practice of the present invention. The objectives and other advantages of the present invention will be realized and attained by means of the elements and combinations particularly pointed out in the description and appended claims.

To achieve these and other advantages, and in accordance with the purposes of the present invention, as embodied and broadly described herein, the present invention relates to a drilling fluid which contains at least one alkali metal formate and preferably at least one surfactant. Additional alkali metal formates, wetting agents, hydrocarbons, solid weighting materials, sealing or fluid loss agents, filtration control agents, and/or polymers to further control viscosity and/or other conventional additives such as organoclays and the like can also be optionally present for purposes of the present invention.

The present invention further relates to a method to drill a well comprising drilling of a well in the presence of the above-mentioned drilling fluid of the present invention.

The present invention further relates to a method to minimize or eliminate solids in a drilling fluid by substituting at least a portion of the solids weighting material with at least one alkali metal formate and preferably at least one surfactant.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are intended to provide a further explanation of the present invention, as claimed.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

The present invention relates to drilling fluids for use in drilling operations. For instance, the drilling fluid can be used in the drilling of a well for hydrocarbon recovery such as oil and/or gas. The drilling fluids of the present invention can also be used in other drilling operations where drilling fluids are used.

The drilling fluid of the present invention contains at least one alkali metal formate or monovalent carboxylic acid salt and preferably at least one surfactant or emulsifier. The drilling fluid of the present invention can contain an emulsion of an aqueous-based solution with a hydrocarbon-based fluid for purposes of forming the drilling fluid wherein the drilling fluid contains at least one alkali metal formate and preferably at least one surfactant along with at least one hydrocarbon-based fluid.

Preferably, the drilling fluid contains cesium formate as the alkali metal formate. More preferably, the drilling fluid contains two or more alkali metal formates, wherein preferably one of the alkali metal formates is cesium formate. A preferred combination of formates includes, but is not limited to, cesium formate with potassium formate. Other combinations of alkali metal formates can be used, such as sodium formate and potassium formate or sodium formate and cesium formate. Essentially, any combination of one or more monovalent carboxylic salts can be used for purposes of the drilling fluids of the present invention.

The alkali metal formates are commercially available. For instance, the cesium formate can be obtained from Cabot Corporation. The cesium formate can be made, for instance, by following the description as set forth in International Published Patent Application No. WO 96/31435, incorporated in its entirety by reference herein. The cesium formate that is present in the drilling fluid, preferably as a soluble salt, as stated above, can be present in any concentration and the cesium formate solution is a liquid at room temperature. Therefore, the concentration of the cesium formate in the drilling fluid can be from about 1% to about 100% by weight, and more preferably is present in an amount of from about 40% to about 95% by weight, and even more preferably is present in the drilling fluid at a range of from about 55% to about 85% by weight or is present in the drilling fluid at a range of from about 70% to about 85% by weight based on the weight of the drilling fluid. Besides the optional ingredients and preferably the surfactant and/or hydrocarbon fluid, the remainder of the drilling fluid can be water or other aqueous solutions. Conventional ingredients used in drilling fluids can also be used with the drilling fluid of the present invention.

Other alkali metal formates that can be used in the present invention are potassium formate and sodium formate which are commercially available. These alkali metal formates can also be prepared in a similar fashion as the cesium formate solution described above, and are also frequently obtained as by-products from ester hydrolysis.

Preferably, with respect to the drilling fluid of the present invention, at least 35% by volume of the fluid in the drilling fluid is an aqueous-based solution containing at least one alkali metal formate. More preferably, at least 50% by volume of the fluids present in the drilling fluid is an aqueous-based solution containing at least one alkali metal formate and even more preferably at least 75% by volume of the fluids present in the drilling fluid of the present invention is an aqueous-based solution containing at least one alkali metal formate. Most preferably, at least 90% by volume of the fluids present in the drilling fluid of the present invention is an aqueous-based solution containing at least one alkali metal formate. In another embodiment, at least 95% or more by volume of the fluids of the present invention contain an aqueous-based solution containing at least one alkali metal formate. In one embodiment, all of the fluids present are an aqueous-based solution containing at least one alkali metal formate wherein essentially no hydrocarbon, or oil is present in the drilling fluid. Since the alkali formate is preferably dissolved in the aqueous solution, the drilling fluid can be solids free since the alkali formate preferably acts as a lubricant and a weighting material.

When a hydrocarbon fluid or synthetic mud fluid is present in the drilling fluids of the present invention, conventional hydrocarbon fluids or synthetic mud fluids can be used in the drilling fluids of the present invention. Examples include, but are not limited to, diesel oil such as diesel oil number 2, crude oil, synthetic oils (such as paraffin oils, olefin oils, vegetable oils, and the like), as well as other conventional hydrocarbon fluids. Combinations of various hydrocarbon fluids or synthetic mud fluids can be used for purposes of the present invention. If a hydrocarbon or synthetic mud fluid is present in the drilling fluid of the present invention, various ratios of the hydrocarbon fluid to the aqueous-based solution described above can be used, such as ratios of 65% by volume hydrocarbon fluid: 35% aqueous based solution to 1% by volume hydrocarbon fluid: 99% by volume aqueous based solution.

When a hydrocarbon fluid is present with the aqueous-based solution containing at least one alkali metal formate, at least one emulsifier or surfactant is preferably present in order to produce an emulsion of the ingredients. Essentially any emulsifier(s) or surfactant(s) capable of forming an emulsion between the hydrocarbon fluid and the aqueous based solution can be used for purposes of the present invention. Examples include, but are not limited to, a dimer trimer acid such as Witco DTA 350, imidazoline, tall oil (stearic acid), Integrity Synvert IV, Integrity Synvert TWA, and the like. Any amount of surfactant or emulsifier can be used to form the emulsion such as from about 1 to about 30 pounds per barrel, wherein a barrel is about 42 gallons.

Other optional ingredients that can be present in the drilling fluids of the present invention include a filtration control agent or pore bridging materials such as Gilsonite and the like. These filtration control agents can be used in conventional amounts.

Other ingredients that can be present in the drilling fluids of the present invention include solid weighting materials such as barite, hematite, and/or calcium carbonate. These solid weighting materials can be used if desired. The amount of solid weighting material, which is optional, can be from about 0.5 pound per barrel to about 500 pounds per barrel.

Another optional ingredient in the drilling fluids of the present invention is a wetting agent which can be helpful in emulsifying the alkali metal formate fluids with the hydrocarbon-based external fluids. An example of a suitable wetting agent is Integrity Synvert TWA. Conventional amounts can be used in combination with the emulsifiers described above in order to achieve desired emulsions of the formate fluids with the hydrocarbon-base external fluids.

Other ingredients that can optionally be present include, but are not limited to, other drilling fluid products such as polymer(s) to add to viscosity, hydrophilic clays, organophilic clays, fluid loss control additives, amine-treated clays, clays treated such that they provide viscosity in non-aqueous fluids, and the like. These other optional ingredients can be used in conventional amounts known to those skilled in the art.

The alkali metal formate that is present as part of the aqueous-based solution can be not fully saturated in the aqueous-based solution so as to permit any remaining water-soluble components to preferably solubilize in the solution along with the alkali metal formate. Thus, the alkali metal formate that is present in the aqueous-based solution can be present in an amount of less than 80% by weight, based on the aqueous-based solution basis, and more preferably is from about 60% to about 80% by weight.

The important advantage of the present invention is the ability for the density of the drilling fluid to be adjusted to any desired density. This can especially be done with the introduction of a combination of alkali metal formates, such as potassium formate with cesium formate. As an example, an aqueous-based portion of the drilling fluid can contain cesium formate which can range from about 1.8 to about 2.4 s.g. This density range can be adjusted with the introduction of potassium formate. For instance, when 0 to 100% by weight of potassium formate is included in the aqueous-based portion of the drilling fluid, the density of the overall aqueous-based portion of the drilling fluid can range from about 1.2 to about 2.4. Thus, the density of the drilling fluid can essentially be “dialed-in” to meet the density needed for the drilling fluid to be used in the drilling of the well bore at the appropriate depths. For lower density ranges, sodium formate can be added to the potassium formate, hence, “dialing-in” lower density drilling fluids.

Thus, the drilling fluids of the present invention make it possible to achieve a variety of different densities and to minimize or completely eliminate the solid weighting material that is present in conventional drilling fluids.

The drilling fluids of the present invention can be introduced into the well bore by any conventional technique such as, but not limited to, being pumped into the drill pipe. Further, the drilling fluids can be recovered using conventional techniques.

The drilling fluids of the present invention can be prepared by mixing all of the components together. When an emulsion is prepared, typically, the components will be mixed together such as by shearing in order to ensure a dispersion that is preferably uniform with respect to the components.

For example, a typical paraffinic hydrocarbon oil such as ESCAID 110, having a density of 0.803 s.g. (6.7 ppg) and a cesium formate solution having a density of 2.2 s.g. (18.36 ppg) when combined in a ratio of 1:1 and by addition of an emulsifier or a series of emulsifiers admixed by shearing, the fluids together can produce an emulsion or microemulsion that has a cesium formate invert phase or (internal phase) and an oil external phase. The density of the combined mixture of this example is 1.51 s.g. (12.6 ppg).

For purposes of the present invention, when a hydrocarbon-based external fluid is used with at least one formate fluid as described above, the formate fluids can be partially or totally emulsified into the hydrocarbon-based fluid. Or, in the alternative, when a majority of the drilling fluid is a formate fluid, the hydrocarbon-based fluid, if present, can be partially or totally emulsified into the formate fluid.

Optionally, the drilling fluids of the present invention can also contain at least one acid. Preferably, the acid is an acid containing at least one carboxylic group and more preferably is formic acid or an acid derivative thereof. Other examples of acids that can be used include, but are not limited to, acetic acid, ascorbic acid, citric acid, tartaric acid, phthalic acid, glycolic acid, and combinations thereof. The acid can be present in various amounts such as from about 1% or less to 25 weight % or more based on the weight of the drilling fluid. The presence of the acid has the capability of adjusting the pH of the drilling fluid as well as providing other benefits to the drilling fluid. When an acid is present, for instance, the alkali metal formate fluid, such as cesium formate, can be present in any molar amount, but is preferably present in an amount of about 3 M. Similarly, the acid, when present, can be present in any molar amount, and is preferably present in an amount of from about 2.2 M to about 15 M. The pH of the drilling fluid can be any pH.

The present invention will be further clarified by the following examples, which are intended to be purely exemplary of the present invention.

EXAMPLES

Various drilling fluid formulations were prepared and tested to determine the ability of the drilling fluids to serve as suitable fluids for drilling.

In the Examples, cesium formate was used and as can be seen in the results summarized in the various tables, a drilling fluid was made that had low or zero solids content and had the capability to “dial-in” various densities using a combination of components described herein.

In the examples, a barrel is generally 42 gallons of liquid. IA-35 is a synthetic oil from Integrity Industries. Integrity Synvis is a viscosifier. Witco DTA 350 is a wetting agent. Baroid Baracarb 50 is calcium carbonate. Initial ES (volts) is electrical stability at the temperature shown below the values. Initial properties refers to apparent viscosity using a Fann 35 viscometer. SA refers to static-aged ES testing and 250 refers to testing at 250° F. for 16 hours. “Silv” refers to a Silverson mixer.

The tests in the Tables were conducted in accordance with Recommended Practice Standard Procedure for Field Testing oil-based drilling fluids, API, 13B-2 (2 nd Ed., Dec. 1, 1991), and Recommended Practice Standard Procedure API Recommended Procedure 13-I (5 th Ed., Jun. 1, 1995), incorporated in their entirety by reference herein.

	Cesium formate, IA - 35 (50/50 mixture, 2.3 s.g. CsF) 2.3 sg csf
	Mixing Procedure:
	1.	Measure out IA - 35
	1A.	Add Synvis, mix 5 minutes
	2.	Add CsF, mix 10 min.
	3.	Add Emulsifier Synvert, mix 10 minutes
	3A.	Add calcium carbonate, mix 10 minutes
	4.	Run initial ES, viscosities at 120° F.
	5.	Put 10 ml sample in a vial, SA for 24 hrs at 75° F.,
		measure volumes
	6.	Hot-roll for 16 hours at 150° F.
	7.	Remix, run rheology, ES, API, HTHP at 150° F.
	8.	Put vials in oven and static-age at 150° F. for 24 hrs,
		measure volumes
	9.	If 150° F. HTHP is good, run at 250° F.
41.6/58.4 oil/csf ratio
	Sample #
	337	338	339
IA - 35,	98.26	98.26	93.26
grams
Cesium	445 (2.366)	445 (2.366)	445 (2.366)
Formate,
grams
Integrity	25	25	20
Emulsifier,
lb/bbl
Integrity	0.5	1	0.5
Synvis,
lb/bbl
Witco	—	—	—
DTA 350,
lb/bbl
Baroid	50	50	50
Baracarb
50, lb/bbl
Initial ES,	103	129	167	166	114	151
volts
Hot-rolled	114	102	148	140	139	138
16 hrs, ES
Initial Properties	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.
600 rpm	162	116	186	118	164	115
300 rpm	93	65	114	67	96	66
200 rpm	67	47	83	49	70	48
100 rpm	40	27	49	29	41	28
6 rpm	8	7	9	6	7	6
3 rpm	6	5	7	5	5	5
Plastic	69	51	72	51	68	49
Viscosity, cP
Yield Pt, lb/	24	14	42	16	28	17
100 ft{circumflex over ( )}2
Gels, 10 sec/	6/7	6/6	6/7	5/6	5/6	5/5
10 min.
Settling in	no	no	no	no	no	no
thermocup
HR 16 hrs
at 150° F.
600 rpm	161	113	187	123	162	114
300 rpm	93	64	116	70	97	66
200 rpm	68	46	86	52	72	48
100 rpm	39	27	52	30	473	28
6 rpm	8	6	10	6	7	6
3 rpm	6	5	8	5	5	4
Plastic	68	49	71	53	65	48
Viscosity, cP
Yield Pt,	25	15	45	17	32	18
lb/100 ft{circumflex over ( )}2
Gels, 10	6/6	5/6	7/9	5/6	6/6	5/5
sec/10 min.
API filt,	1.0	0.2	0.4
ml total
API filt,	—	—	—
ml oil
API filt,	1.0	0.2	0.4
ml emulsion
API filt,	—	—	—
ml brine
HTHP at			0.2
150° F., ml
HTHP at			11.4
250° F., ml
250° F. oil			0.0
250° F.			6.8
emulsion
250° F. brine			4.6
Comments
NOTE:
1. Sample 337 and 338 looked grainy with 15 lb/bbl Synvert V.
Concentration was increased to 25 lb/bbl.
After hot-rolling at 150° F., #337
and #338 still appear grainy.
2. Mud weight of 339 is 14.7 lb/gal (CsF in
337-339 is 2.366 s.g)
41.6/58.4 oil/csf ratio
	Sample #
	340	347	348
IA - 35, grams	93.26	88.26	88.26
Cesium	455 (2.366)	445 (2.3)	445 (2.3)
Formate,
grams
Integrity	20	25	25
Emulsifier,
lb/bbl
Integrity	1	—	—
Synvis,
lb/bbl
Witco	—	0.5	1
DTA 350,
lb/bbl
Baroid	50	50	50
Baracarb 50,
lb/bbl
Initial ES,	117	128	212	192	205	243
volts
Hot-rolled	122	118	148	145	252	247
16 hrs, ES
Initial Properties	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.
600 rpm	183	126	177	132	182	132
300 rpm	109	73	106	78	111	80
200 rpm	80	53	77	57	83	61
100 rpm	47	31	46	347	52	38
6 rpm	8	6	8	7	10	8
3 rpm	6	5	6	5	7	6
Plastic	74	53	71	54	71	52
Viscosity, cP
Yield Pt, lb/	35	20	35	24	40	28
100 ft{circumflex over ( )}2
Gels, 10 sec/	6/7	5/5	6/6	6/6	8/8	6/7
10 min.
Settling in	no	no	no	no	no	no
thermocup
HR 16 hrs at
150° F.
600 rpm	184	129	179	140	184	144
300 rpm	111	75	109	84	113	88
200 rpm	82	55	80	62	85	66
100 rpm	49	32	48	37	52	41
6 rpm	8	6	8	7	10	9
3 rpm	6	5	6	5	8	7
Plastic	73	56	70	56	71	56
Viscosity, cP
Yield Pt,	38	28	39	32	42	32
lb/100 ft{circumflex over ( )}2
Gels, 10	6/7	5/6	6/6	5/5	8/8	7/9
sec/10 min.
API filt,	0.3	3.5	6.2
ml total
API filt,	—	—	—
ml oil
API filt,	0.3	3.5	6.2
ml emulsion
API filt,	—	—	—
ml brine
HTHP at	0.2	19.4	(0.8 brine)
150° F., ml
HTHP at	4.4
250° F. ml
250° F. oil	0.0
250° F.	3.2
emulsion
250° F.	1.2
brine
Comments
NOTE
1. Mud weight of 339 is 14.7 lb/gal (CsF in 340 is
2.366 s.g)
2. Mud weight of 347 is 14.6 lb/gal (CsF in 347-348
is 2.30 s.g)
41.6/58.4 oil/csf ratio
	Sample #
	341	342	343	344	345	346
IA - 35,	88.26	88.26	98.26	98.26	93.26	93.26
grams
Cesium	445	445	445	445	445	445
Formate,
grams
Integrity	25	25	15	15	20	20
Emulsifier,
lb/bbl
Integrity	0.5	1	—	—	—	—
Synvis,
lb/bbl
Witco	—	—	0.5	1	0.5	1
DTA 350,
lb/bbl
Baroid	50	50	50	50	50	50
Baracarb 50,
lb/bbl

Cesium Formate, Escaid 110 (50/50 mixture)
Mixing Procedure:
1. Measure out Escaid 110, add Organoclay, mix 10 minutes
2. Add emulsifier(s), mix 5 minutes, add Gilsonite, mix 10 minutes
3. Add CsF, mix 10 min on HB, add CaCO3, mix 10 min on HB
4. Run initial ES, viscosities at 120 F.
5. Put 10 ml sample in vial, SA for 24 hrs at 75 F., measure volume
6. Hot Roll for 16 hrs. at 150 F.
7. Remix, run rheology es, HPHT @ 250 F.
8. Put vial in oven SA 24 hrs @ 150 F.
Sample #	E-1	E-2	E-3	E-4
Integrity Synvert IV, lb/bbl	10	15	10	10
Dimer-Trimer acid, lb/bbl	0	0	0	1
Integrity Synvert TWA, lb/bbl	0	0	0	6
Organoclay, lb/bbl	0	0	4	4
Gilsonite, lb/bbl	0	0	5	5
CaCo3, lb/bbl	0	0	50	50
ES @ 120 F.	225	289	170	175
Hot-rolled 16 hrs, ES @ 120 F.	395	440	365	350
Initial Properties
600 rpm @ 120 F.	28	30	85	92
300 rpm @ 120 F.	15	16	40	50
200 rpm @ 120 F.	10	11	31	41
100 rpm @ 120 F.	5	6	15	25
6 rpm @ 120 F.	0	1	3	6
3 rpm @ 120 F.	0	0	1	5
Plastic Viscosity, cP	13	14	45	42
Yield Point, lb/100 ftsq	2	2	5	8
Gels, 10 sec/10 min	0/0	0/1	1/4	5/8
HR 16 hrs @ 150 F.
600 rpm @ 120 F.	31	33	96	110
300 rpm @ 120 F.	16	18	49	62
200 rpm @ 120 F.	10	12	35	53
100 rpm @ 120 F.	5	6	20	40
6 rpm @ 120 F.	0	2	4	10
3 rpm @ 120 F.	0	1	2	6
Plastic Viscosity, cP	15	15	47	48
Yield Point, lb/100 ftsq	1	3	4	14
Gels, 10 sec/10 min.	0/0	1/1	3/4	7/9
HPHT @ 250 F., ml	30	26	8	6
Water in filtrate, ml	4	3	0	0
24 hrs @ 75 F.
Free Oil %	10	8	5	3
Emulsion %	90	92	95	97
Free Brine %	0	0	0	0

Cesium Formate, IA-35 (75/25 mixture)
	Mixing Procedure:
	1. Measure out IA-35, add Organoclay, mix 10 minutes
	2. Add emulsifier(s), mix 5 minutes, add Gilsonite, mix 10 minutes
	3. Add CsF, mix 10 min on HB, add CaCO3, mix 10 min on HB
	4. Run initial ES, viscosities at 120 F.
	5. Put 10 ml sample in vial, SA for 24 hrs at 75 F. measure volume
	6. Hot Roll for 16 hrs. at 250 F.
	7. Remix, run rheology es, HPHT @ 150 F.
	8. Put vials in oven SA 24 hrs @ 150 F.
	Sample #
	1	2	3	4	5
Integrity Synvert IV, lb/bbl	10	15	10	10	15
Dimer-Trimer acid, lb/bbl	0	0	0	1	1
Integrity Synvert TWA, lb/bbl	0	0	0	6	6
Organoclay, lb/bbl	0	0	4	4	4
Gilsonite, lb/bbl	0	0	5	5	5
CaCo3, lb/bbl	0	0	50	50	50
ES @ 120 F.	226	250	270	175	225
Hot-rolled 16 hrs, ES @ 120 F.	185	200
Initial Properties
600 rpm @ 120 F.	251	265	t	t	t
300 rpm @ 120 F.	169	172	o	o	o
200 rpm @ 120 F.	135	133	o	o	o
100 rpm @ 120 F.	92	184
6 rpm @ 120 F.	26	13	t	t	t
3 rpm @ 120 F.	20	8	h	h	h
			i	i	i
Plastic Viscosity, cP	82	93	c	c	c
Yield Point, lb/100 ftsq	87	79	k	k	k
Gels, 10 sec/10 min	24/28	8/12
HR 16 hrs @ 150 F.
600 rpm @ 120 F.	276	259
300 rpm @ 120 F.	175	166
200 rpm @ 120 F.	140	101
100 rpm @ 120 F.	99	22
6 rpm @ 120 F.	29	14
3 rpm @ 120 F.	22	8
Plastic Viscosity, cP	101	93
Yield Point, lb/100 ftsq	74	73
Gels, 10 sec/10 min.	22/23	8/12
HPHT @ 250 F., ml	23	16
Water in filtrate, ml	8	4
24 hrs @ 75 F.
Free Oil %	1	0	0
Emulsion %	99	100	100
Free Brine %	0	0	0
24 hrs @ 150 F.
Free oil %	2	2	0
Emulsion %	98	98	100
Free Brine %	0	0	0
Observational Notes:
Emulsion is clear at temperatures above 130 F.
Amount of shear imparted to system is directly related to emulsion stability
Heating the emulsion to 150 F. acts to stabilize emulsion (similar to shearing)
Oil/Water ratios as low as 25/75 are achievable with this system

Cesium Formate, IA-35 (50/50 mixture)
Mixing Procedure:
1. Measure out IA-35, add Organoclay, mix 10 minutes
2. Add emulsifier(s), mix 5 minutes, add Gilsonite, mix 10 minutes
3. Add CsF, mix 10 min on HB, add CaCO3, mix 10 min on HB
4. Run initial ES, viscosities at 120 F.
5. Put 10 ml sample in vial, SA for 24 hrs at 75 F., measure volume
6. Hot Roll for 16 hrs. at 150 F.
7. Remix, run rheology es, HPHT @ 250 F.
8. Put vials in oven SA 24 hrs @ 150 F.
	Sample #
	1	2	3	4	5
Integrity Synvert IV, lb/bbl	10	15	10	10	15
Dimer-Trimer acid, lb/bbl	0	0	0	1	1
Integrity Synvert TWA, lb/bbl	0	0	0	6	6
Organoclay, lb/bbl	0	0	4	4	4
Gilsonite, lb/bbl	0	0	5	5	5
CaCo3, lb/bbl	0	0	50	50	50
ES @ 120 F.	226	255	241	150	231
Hot-rolled 16 hrs, ES @ 120 F.	425	475	427	320	444
Initial Properties
600 rpm @ 120 F.	39	42	162	181	155
300 rpm @ 120 F.	20	22	93	131	92
200 rpm @ 120 F.	14	15	66	110	67
100 rpm @ 120 F.	7	8	36	81	39
6 rpm @ 120 F.	0	1	3	33	6
3 rpm @ 120 F.	0	0	2	28	4
Plastic Viscosity, cP	19	20	69	50	63
Yield Point, lb/100 ftsq	1	2	24	81	29
Gels, 10 sec/10 min	0/0	0/2	3/7	29/32	7/7
HR 16 hrs @ 150 F.
600 rpm @ 120 F.	51	55	169	195	188
300 rpm @ 120 F.	27	29	101	145	114
200 rpm @ 120 F.	14	14	75	113	86
100 rpm @ 120 F.	9	10	43	87	51
6 rpm @ 120 F.	1	1	4	37	8
3 rpm @ 120 F.	0	1	2	30	5
Plastic Viscosity, cP	24	26	68	50	74
Yield Point, lb/100 ftsq	3	3	33	95	40
Gels, 10 sec/10 min.	0/0	0/1	3/3	33/35	5/6
HPHT @ 250 F., ml	28	22	15	14	6
Water in filtrate, ml	4	3	2	2	0
24 hrs @ 75 F.
Free Oil %	5	10	4	3	2
Emulsion %	95	90	96	97	98
Free Brine %	0	0	0	0	0
24 hrs @ 150 F.
Free oil %	18	15	10	0
Emulsion %	92	85	90	94
Free Brine %	0	0	0	0

Cesium formate, Escaid 110 (50/50 mixture)
175 ml Escaid 110 (0.803 sg) - (140.5 grams)
175 ml Cesium Formate (2.2 sg) - (385 grams)
Mixing Procedure:
1.	Measure out Escaid 110, add Geltone II, mix 10 minutes
2.	Add emulsifiers (Below in bold), mix 5 minutes, add Barablock, mix 10 minutes
3.	Add CsF, mix 10 min. on HB, add Lo-Wate, mix 10 min. on HB
4.	Run initial ES, viscosities at 120° F.
5.	Put 10 ml sample in a vial, SA for 24 hrs at 75° F., measure volumes
6.	Hot-roll for 16 hours at 150° F.
7.	Remix, run rheology, ES, API, HTHP at 150° F.
8.	Put vials in oven and static-age at 150° F. for 24 hrs, measure volumes
9.	If 150° F. HTHP is good, run at 250° F.
	Sample #
	225	226	227	228	229	230
Integrity	7	7	7	7	7	7
Synvert II
(Lot# 991512),
lb/bbl
Witco DTA 350	1	1	1	1	1	1
(dimer-trimer),
lb/bbl
Integrity	2	4	6	2	4	6
Synvert TWA
(Jan. 24, 2000,
D116), lb/bbl
Baroid Geltone	—	—	—	4	4	4
II, lb/bbl
Baroid	—	—	—	—	—	—
Barablock 400,
lb/bbl
M-I Lo-Wate,	50	50	50	50	50	50
lb/bbl
Initial ES,	107	194	247	127	123	128
volts
Hot-rolled 16	426	450	290	150	185	170
hrs, ES
Initial Properties
600 rpm at	80	67	80	99	74	87
75° F.
300 rpm	58	48	60	75	52	60
200 rpm	49	40	51	64	43	48
100 rpm	37	31	39	49	31	35
6 rpm	13	10	13	18	12	13
3 rpm	10	5	4	15	10	11
Plastic	22	19	20	24	22	27
Viscosity, cP
Yield Pt,	36	29	40	51	30	33
lb/100 ft{circumflex over ( )}2
Gels, 10 sec/10 min.	11/7	5/7	7/3	15/15	10/10	10/11
HR 16 hrs at 150° F.
600 rpm at	71	89	95	94	75	70
120° F.
300 rpm	53	69	74	68	52	48
200 rpm	44	59	63	56	43	39
100 rpm	34	45	49	42	31	28
6 rpm	10	12	12	17	12	10
3 rpm	4	5	4	13	10	8
Plastic	18	20	21	26	23	22
Viscosity, cP
Yield Pt,	35	49	53	42	29	26
lb/100 ft{circumflex over ( )}2
Gels,	7/4	9/4	10/4	12/13	10/11	9/9
10 sec/10 min.
API filtrate,	0.8	1.1	1.1	1.6	0.9	0.6
ml
API Filtrate,	0	0	0	0	0	0
oil
API Filtrate,	0	0	0	0	0	0
brine
HTHP at	8.8	3.0	5.0	3.5	1.6	0.8
150° F., ml
Water in	6.0	2.5	2.5	1.5	0.4	0.0
filtrate?
HTHP at	24.0	18.0	12.0	8.2	4.2	2.5
250° F., ml
Water in	12.0	9.0	3.1	2.6	1.7	0.6
filtrate?
24 hrs at 75° F.
Total fluid	34	35	34	35	36	33
heighth
free oil	6	3	2	1	1	2
heighth
emusion	28	32	32	34	35	31
heighth
free brine	0	0	0	0	0	0
heighth
free oil, %	18%	9%	6%	3%	3%	6%
emusion, %	82%	91%	94%	97%	97%	94%
free brine, %	0%	0%	0%	0%	0%	0%
24 hrs at 150° F.
Total fluid	34	36	35	35	37	32
heighth
free oil	8	8	6	3	3	4
heighth
emusion	26	28	29	32	34	28
heighth
free brine	0	0	0	0	0	0
heighth
free oil, %	24%	22%	17%	9%	8%	13%
emusion, %	76%	78%	83%	91%	92%	88%
free brine, %	0%	0%	0%	0%	0%	0%
Difference (72 hrs/24 hrs at 150° F.)
free oil, %	6%	14%	11%	6%	5%	6%
emusion, %	−6%	−14%	−11%	−6%	−5%	−6%
free brine, %	0%	0%	0%	0%	0%	0%
	Sample #
	231	232	233	234	235	236
Integrity	7	7	7	7	7	7
Synvert II
(Lot# 991512),
lb/bbl
Witco DTA 350	1	1	1	1	1	1
(dimer-trimer),
lb/bbl
Integrity	2	4	6	2	4	6
Synvert TWA
(Jan. 24, 2000,
D116), lb/bbl
Baroid Geltone	—	—	—	4	4	4
II, lb/bbl
Baroid	5	5	5	5	5	5
Barablock
400, lb/bbl
M-I Lo-Wate,	50	50	50	50	50	50
lb/bbl
Initial ES,	139	263	249	105	133	161
volts
Hot-rolled	402	314	307	144	196	245
16 hrs, ES
Initial Properties
600 rpm at	81	90	85	86	81	84
75° F.
300 rpm	63	69	65	62	57	60
200 rpm	52	59	55	50	47	49
100 rpm	40	46	43	37	34	37
6 rpm	17	14	14	12	14	14
3 rpm	12	5	5	10	12	12
Plastic	18	21	20	24	24	24
Viscosity, cP
Yield Pt,	45	48	45	38	33	36
lb/100 ft{circumflex over ( )}2
Gels, 10	17/15	10/5	11/6	10/11	12/13	12/12
sec/10 min.
HR 16 hrs at 150° F.
600 rpm at	111	118	122	63	90	110
120° F.
300 rpm	84	92	96	43	62	76
200 rpm	71	78	83	35	50	62
100 rpm	53	61	65	25	37	45
6 rpm	17	18	21	9	13	16
3 rpm	7	7	7	7	11	14
Plastic	27	26	26	20	28	34
Viscosity, cP
Yield Pt,	57	66	70	23	34	42
lb/100 ft{circumflex over ( )}2
Gels, 10	13/5	12/6	13/5	7/8	10/11	13/14
sec/10 min.
API filtrate,	1.2	1.2	0.3	0.2	0.2	0.0
ml
API Filtrate,	0	0	0	0	0	0
oil
API Filtrate,	0	0	0	0	0	0
brine
HTHP at	2.6	2.0	1.4	2.0	trace	trace
150° F., ml
Water in	0.0	0.0	0.0	0.0	0.0	0.0
filtrate?
HTHP at	9.0	8.0	6.0	7.0	5.0	4.0
250° F., ml
Water in	0.0	0.0	0.0	0.0	0.0	0.0
filtrate?
24 hrs at 75° F.
Total fluid	35	35	35	34	34	34
heighth
free oil	3	2	3	2	1	1
heighth
emusion	32	33	32	32	33	33
heighth
free brine	0	0	0	0	0	0
heighth
free oil, %	9%	6%	9%	6%	3%	3%
emusion, %	91%	94%	91%	94%	97%	97%
free brine, %	0%	0%	0%	0%	0%	0%
24 hrs at 150° F.
Total fluid	35	36	35	34	35	35
heighth
free oil	7	6	6	6	4	3
heighth
emusion	28	30	29	28	31	32
heighth
free brine	0	0	0	0	0	0
heighth
free oil, %	20%	17%	17%	18%	11%	9%
emusion, %	80%	83%	83%	82%	89%	91%
free brine, %	0%	0%	0%	0%	0%	0%
Difference (72 hrs/24 hrs at 150° F.)
free oil, %	11%	11%	9%	12%	8%	6%
emusion, %	−11%	−11%	−9%	−12%	−8%	−6%
free brine, %	6%	0%	0%	0%	0%	0%

	Mixing Order:
	1. Measure out IA 35 base oil
	2. Add Synvert IV
	3. Add cesium formate
	4. Mix on HB, Silverson to 135° F.
	Sample #
	1	2	3	4	5
IA-35, %	90	75	50	25	10
Synvert IV,	20	20	20	20	20
lb/bbl
2.2 s.g. Cs	10	25	50	75	90
Formate, %
Initial Rheologies
Mud weight,	7.81	9.4	11.94	14.47	17.18
lb/gal
600 rpm at	7	13	42	>300	too
120° F.
300 rpm	4	7	21	274	thick
200 rpm	3	5	14	218	to
100 rpm	2	3	7	149	measure
6 rpm	0.2	0.5	1	38
3 rpm	0.2	0.5	0.5	28
PV	3	6	21	—	—
YP	1	1	0	—	—
Gels	.5/.5	1/1	1/1	28/32	—
ES	373	310	362	328	133
Vials 16 hrs at 75° F.
Total Heighth	32	32	32	31
Oil	18	1	0	0
Emulsion	14	31	32	31
Formate
Samples H.R. for 16 hours at 150° F.
600 rpm at	6	13	45	>300	too
120° F.
300 rpm	3	7	23	273	thick
200 rpm	2	4	16	222	to
100 rpm	1	2	8	158	measure
6 rpm	0	0	2	49
3 rpm	0	0	2	40
PV	3	6	22	—	—
YP	0	1	1	—	—
Gels	1/1	0/0	2/2	38/42	—
ES	1069	211	232	271	115
Vials 7 hrs at 150° F.
Total Heighth	32	32	32	32
Oil	22	3	1	0
Emulsion	10	29	31	32
Formate
Vials 64 hrs at 200° F.
Total Heighth	105	103	100	100	105
Oil	89	66	40	0	0
Emulsion	8	12	60	100	105
Formate	8	25	0	0	0
Vials 64 hrs at 250° F.
Total Heighth	103	100	100	100	110
Oil	95	70	30	32	0
Emulsion	8	7	65	60	110
Formate	0	23	5	8	0
Vials 64 hrs at 300° F.
Total Heighth	102	105	102	102	104
Oil	92	70	42	32*	19*
Emulsion	10	10	10
Formate	0	25	50	70	85
*combination oil and emulsion

Integrity Synvert IV Sample 1 gallon can
	Test Procedure
	1.	Mix sample
	2.	Place aliquots of sample in large test tubes
	3.	Static-age samples for 24 hours at 200, 250, and 300 F.,
		300 psi N2
	4.	Static-age samples for 72 hours at 200, 250, and 300 F.,
		300 psi N2
	5.	Measure total heighth, oil, emulsion, and brine
	200° F.	250° F.	300° F.
24 hour tests
Total heighth, mm	100	99	99
Free Oil, mm	9	16	30
Emulsion, mm	84	73	46
Free Brine, mm	7	10	23
% Oil	9.0%	16.2%	30.3%
% Emulsion	84.0%	73.7%	46.5%
% Brine	7.0%	10.1%	23.2%
72 hour tests
Total heighth, mm	96	101	97
Free Oil, mm	5	10	30
Emulsion, mm	81	71	22
Free Brine, mm	10	20	45
% Oil	5.2%	9.9%	30.9%
% Emulsion	84.4%	70.3%	22.7%
% Brine	10.4%	19.8%	46.4%
Note:
the 24 hr 300° F., and the 72 hour 200 and 250° F. fluids appeared
to have two phases in the emulsion portion. One phase is more
distinctly oil and the second phase is more distinctly emulsion.
Sample of 50/50 mix from Integrity (one gallon can)
	600 rpm at 75° F.	90
	300 rpm	49
	200 rpm	34
	100 rpm	18
	6 rpm	2
	3 rpm	1
	PV	41
	YP	8
	Gels	2/2
	ES	457
Integrity Turpene-Formate Sample
	3 days	7 days
	Vials 3 and 7 days at 200° F.
	Total Heighth	50	52
	Oil	20	15
	Emulsion	0	0
	Formate	30	37
	Vials 3 and 7 days at 250° F.
	Total Heighth	54	51
	Oil	17	15
	Emulsion	0	0
	Formate	37	36
	Vials 3 and 7 days at 300° F.
	Total Heighth	51	50
	Oil	15	15
	Emulsion	0	0
	Formate	36	35
	Sample #
		SA 250	SA 250		SA 250	SA 250
		Initial	Silv.		Initial	Silv.
	349	349.5	349.75	350	350.5	350.75	353
IA - 35, grams	94.26	94.26	94.26	94.26	94.26	94.26	89.26
Cesium Formate,	445	445	445	445	445	445	445
grams
Integrity	20	20	20	20	20	20	25
Emulsifier,
lb/bbl
Integrity	0.5	0.5	0.5	0.5	0.5	0.5	0.5
Synvis,
lb/bbl
Witco DTA	—	—	—	0.5	0.5	0.5	—
350, lb/bbl
Baroid	—	—	—	—	—	—	—
Barablock,
lb/bbl
M-I Lo Wate,	50	50	50	50	50	50	50
lb/bbl
Initial	227			256			301
ES, volts
Hot-rolled	109			209			339
16 hrs, ES
Static-aged		113			154
ES, volts
Initial Properties	120° F.	120° F.	120° F.	120° F.	120° F.	120° F.	120° F.
600 rpm	188	147	—	179	148	—	203
300 rpm	113	90	—	108	88	—	122
200 rpm	83	68	—	80	65	—	90
100 rpm	49	41	—	48	39	—	53
6 rpm	8	6	—	6	6	—	7
3 rpm	5	4	—	4	4	—	5
Plastic	75	57	—	71	60	—	81
Viscosity, cP
Yield Pt,	38	33	—	37	28	—	41
lb/100 ft{circumflex over ( )}2
Gels, 10	5/6	5/6	—	4/5	4/6	—	6/6
sec/10 min.
Settling in	no	no	—	no	no	—	no
thermocup
Initial	253			266			295
ES, volts
Hot-rolled	205	145	331	222	175	330	242
16 hrs, ES
HR 16 hrs at 150° F.	150° F.	150° F.	150° F.	150° F.	150° F.	150° F.	150° F.
600 rpm	137	98	121	137	104	121	158
300 rpm	81	58	70	82	60	70	95
200 rpm	60	42	51	61	44	51	70
100 rpm	36	25	30	37	26	30	42
6 rpm	7	4	5	7	5	5	8
3 rpm	5	3	3	5	3	3	6
Plastic	56	40	51	55	44	51	63
Viscosity, cP
Yield Pt,	25	18	19	27	16	19	32
lb/100 ft{circumflex over ( )}2
Gels, 10	6/6	3/3	3/4	5/5	3/4	3/4	6/6
sec/10 min.
API filt,	0.7	—	—	0.4	—	—	0.3
ml total
API filt,	0	—	—	0	—	—	0
ml oil
API filt,	0.7	—	—	0.4	—	—	0.3
ml emulsion
API filt,	0.0	—	—	0.0	—	—	0.0
ml brine
HTHP at	3.2	—	1.6	8.8	—	2.0	4.8
250° F., ml
250° F.	2.4	—	—	6	—	—	3.6
oil
250° F.	0.8	—	1.6	2.8	—	2.0	1.2
emulsion
250° F.	—	—	—	—	—	—	—
brine
Free Oil, %			22%			25%
	Sample #
	SA 250	SA 250		SA 250	SA 250
	Initial	Silv.		Initial	Silv.
	353.5	353.75	354	354.5	354.75
IA - 35, grams	89.26	89.26	89.26	89.26	89.26
Cesium Formate,	445	445	445	445	445
grams
Integrity	25	25	25	25	25
Emulsifier,
lb/bbl
Integrity	0.5	0.5	0.5	0.5	0.5
Synvis,
lb/bbl
Witco DTA 350,	—	—	0.5	0.5	0.5
lb/bbl
Baroid	—	—	—	—	—
Barablock,
lb/bbl
M-I Lo Wate,	50	50	50	50	50
lb/bbl
Initial ES,			384
volts
Hot-rolled 16			306
hrs, ES
Static-aged	150			240
ES, volts
Initial Properties	120° F.	120° F.	120° F.	120° F.	120° F.
600 rpm	159	—	224	205	—
300 rpm	97	—	138	125	—
200 rpm	73	—	103	93	—
100 rpm	44	—	65	56	—
6 rpm	7	—	10	9	—
3 rpm	5	—	7	7	—
Plastic	62	—	86	80	—
Viscosity, cP
Yield Pt,	35	—	52	45	—
lb/100 ft{circumflex over ( )}2
Gels, 10	6/7	—	7/8		—
sec/10 min.
Settling in	no	—	no	no	—
thermocup
Initial			387
ES, volts
Hot-rolled	161	369	314	218	336
16 hrs, ES
HR 16 hrs at 150° F.	150° F.	150° F.	150° F.	150° F.	150° F.
600 rpm	114	136	167	133	157
300 rpm	68	80	102	78	94
200 rpm	50	59	76	57	69
100 rpm	30	35	47	34	41
6 rpm	5	7	10	6	6
3 rpm	4	5	8	4	4
Plastic	46	56	65	55	63
Viscosity, cP
Yield Pt,	22	24	37	23	31
lb/100 ft{circumflex over ( )}2
Gels, 10	4/5	5/6	8/8	5/5	5/5
sec/10 min.
API filt,	—	—	1.8	—	—
ml total
API filt,	—	—	0.1	—	—
ml oil
API filt,	—	—	1.7	—	—
ml emulsion
API filt,	—	—	0.0	—	—
ml brine
HTHP at	—	2.4	3.6	—	4.8
250° F., ml
250° F. oil	—	—	0.4	—	0.3
250° F.	—	1.0	3.2	—	2.5
emulsion
250° F.	—	1.4	—	—	2.0
brine
Free Oil, %		25%			25%
	Sample #
	351	355	359
IA - 35,	94.26	89.26	84.26
grams
Cesium	445 (2.3)	445 (2.3)	445 (2.3)
Formate,
grams
Integrity	20	25	30
Emulsifier,
lb/bbl
Integrity	0.5	0.5	0.5
Synvis,
lb/bbl
Witco	0.5	0.5	0.5
DTA 350,
lb/bbl
Baroid	10	10	10
Barablock,
lb/bbl
M-I Lo Wate,	50	50	50
lb/bbl
Initial ES,	301	300	357	365	440	492
volts
Hot-rolled	308	348	328	325	368	389
16 hrs, ES
Initial Properties	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.
600 rpm	195	193	241	227	300+	300+
300 rpm	117	120	147	143	253	233
200 rpm	87	91	111	110	196	182
100 rpm	53	56	70	70	127	119
6 rpm	7	10	12	15	28	29
3 rpm	5	7	8	11	20	22
Plastic	78	73	94	84	—	—
Viscosity, cP
Yield Pt,	39	47	53	59	—	—
lb/100 ft{circumflex over ( )}2
Gels, 10	5/6	8/9	8/10	11/14	19/22	22/26
sec/10 min.
Settling in	no	no	1	2	9	10
thermocup
HR 16 hrs at
150° F.
600 rpm	300+	226	300+	274	300+	300+
300 rpm	201	140	246	171	300+	242
200 rpm	154	106	188	129	282	186
100 rpm	98	67	119	81	181	121
6 rpm	20	15	25	19	42	32
3 rpm	15	11	19	15	32	26
Plastic	—	86	—	103	—	—
Viscosity,
cP
Yield Pt,	—	54	—	68	—	—
lb/
100 ft{circumflex over ( )}2
Gels, 10	14/19	11/12	18/22	14/15	32/33	25/27
sec/10
min.
API filt,	0	0.0	0.0
ml total
API filt,	—	0.0	0.0
ml oil
API filt,	0	0.0	0.0
ml emulsion
API filt,	—	0.0	0.0
ml brine
HTHP at
150° F., ml
HTHP at	trace	1.2	trace
250° F., ml
250° F.		0.0	0.0
oil
250° F.		1.2	trace
emulsion
250° F.		0.0	0.0
brine

Cesium formate, IA - 35 (42/58 mixture, 2.3 s.g. CsF) 2.3 sg csf
Mixing Procedure:
1.	Measure out IA - 35
2.	Add Synvis, mix 5 minutes
3.	Add CsF, mix 10 min.
4.	Add Synvert 5, mix 10 minutes
5.	Add DTA 350, mix on Silverson to 120° F.
6.	Add calcium carbonate, mix 10 minutes on HB
7.	Run initial ES, viscosities at 120° F.
8.	Put 10 ml sample in a vial, SA for 24 hrs at 75° F., measure
9.	Hot-roll for 16 hours at 150° F.
10.	Remix, run rheology, ES, API, HTHP at 150° F.
11.	Put vials in oven and static-age at 150° F. for 24 hrs, measure
12.	If 150° F. HTHP is good, run at 250° F.
	Sample #
	349	350	351	352
IA - 35,	94.26	94.26	94.26	94.26
grams
Cesium	445 (2.3)	445 (2.3)	445 (2.3)	445 (2.3)
Formate,
grams
Integrity	20	20	20	20
Emulsifier,
lb/bbl
Integrity	0.5	0.5	0.5	0.5
Synvis,
lb/bbl
Witco DTA	—	0.5	0.5	1.0
350, lb/bbl
Baroid	—	—	10	—
Barablock,
lb/bbl
M-I Lo Wate,	50	50	50	50
lb/bbl
Initial	227	253	256	266	301	300	283	365
ES, volts
Hot-rolled	109	205	209	222	308	348	262	276
16 hrs, ES
Initial Properties	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.
600 rpm	188	138	179	134	195	193	179	146
300 rpm	113	81	108	80	117	120	112	92
200 rpm	83	59	80	59	87	91	84	70
100 rpm	49	35	48	35	53	56	53	43
6 rpm	8	6	6	5	7	10	7	6
3 rpm	5	5	4	4	5	7	4	4
Plastic	75	57	71	54	78	73	67	54
Viscosity, cP
Yield Pt,	38	24	37	26	39	47	45	38
lb/100 ft{circumflex over ( )}2
Gels, 10	5/6	5/5	4/5	4/5	5/6	8/9	4/5	5/5
sec/10 min.
Settling in	no	no	no	no	no	no	no	no
thermocup
HR 16 hrs
at 150° F.
600 rpm	187	137	196	137	300+	226	189	143
300 rpm	114	81	120	82	201	140	119	90
200 rpm	85	60	90	61	154	106	91	69
100 rpm	52	36	56	37	98	67	60	44
6 rpm	9	7	9	7	20	15	12	9
3 rpm	7	5	7	5	15	11	8	6
Plastic	73	56	76	55	—	86	70	53
Viscosity, cP
Yield Pt,	41	25	44	27	—	54	49	37
lb/100 ft{circumflex over ( )}2
Gels, 10	7/7	6/6	6/8	5/5	14/19	11/12	8/10	6/7
sec/10 min.
API filt,	0.7	0.4	0	1.2
ml total
API filt,	—	—	—	0.1
ml oil
API filt,	0.7	0.4	0	1.1
ml emulsion
API filt,	—	—	—	—
ml brine
HTHP at	—	—
150° F., ml
HTHP at	3.2	8.8	trace	3.6
250° F., ml
250° F. oil	2.4	6.0		2.8
250° F.	0.8	2.8		0.8
emulsion
250° F.	0.0	0.0		0.0
brine
Comments
24 hrs at
75° F.
Total fluid	38	38	38	38
heighth
free oil	0	0	0	0
heighth
emusion	38	38	38	38
heighth
free brine	0	0	0	0
heighth
free oil, %	0	0	0	0
emusion, %	100%	100%	100%	100%
free brine, %	0	0	0	0
24 hrs at
150° F.
Total fluid	38	38	38	38
heighth
free oil	0	0	0	0
heighth
emusion	38	38	38	38
heighth
free brine	0	0	0	0
heighth
free oil, %	0	0	0	0
emusion, %	100%	100%	100%	100%
free brine, %	0	0	0	0
	Sample #
	355	356	357	358
IA - 35, grams	89.26	89.26	84.26	84.26
Cesium Formate,	445 (2.3)	445 (2.3)	445 (2.3)	445 (2.3)
grams
Integrity	25	25	30	30
Emulsifier,
lb/bbl
Integrity	0.5	0.5	0.5	0.5
Synvis,
lb/bbl
Witco DTA	0.5	1.0	—	0.5
350, lb/bbl
Baroid	10	—	—	—
Barablock,
lb/bbl
M-I Lo Wate,	50	50	50	50
lb/bbl
Initial	357	365	329	311	335	316	344	321
ES, volts
Hot-rolled	328	325	307	307	298	301	301	272
16 hrs, ES
Initial Properties	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.
600 rpm	241	227	196	154	235	182	245	190
300 rpm	147	143	121	95	147	110	150	116
200 rpm	111	110	92	72	108	82	113	86
100 rpm	70	70	59	46	67	51	70	53
6 rpm	12	15	11	10	13	11	13	11
3 rpm	8	11	8	7	10	8	9	8
Plastic	94	84	75	59	88	72	95	74
Viscosity, cP
Yield Ft,	53	59	46	36	59	38	55	42
lb/100 ft{circumflex over ( )}2
Gels, 10	8/10	11/14	8/9	7/8	9/10	9/9	9/10	8/9
sec/10 min.
Settling in	1	2	3	4	5	6	7	8
thermocup
HR 16 hrs
at 150° F.
600 rpm	300+	274	201	153	229	174	245	185
300 rpm	246	171	124	94	140	106	151	112
200 rpm	188	129	95	71	105	79	114	84
100 rpm	119	81	60	49	65	49	70	52
6 rpm	25	19	12	10	13	12	14	11
3 rpm	19	15	9	8	10	9	10	8
Plastic	—	103	77	59	89	68	94	73
Viscosity, cP
Yield Pt,	—	68	47	35	51	38	57	39
lb/100 ft{circumflex over ( )}2
Gels, 10	18/22	14/15	9/10	8/8	10/10	9/10	10/11	8/9
sec/10 min.
API filt,	0.0	1.8	0.0	1.0
ml total
API filt,	0.0	0.1	0.0	trace
ml oil
API filt,	0.0	1.7	0.0	1.0
ml emulsion
API filt,	0.0	0.0	0.0	0.0
ml brine
HTHP at
150° F., ml
HTHP at	1.2	7.4	4.8	4.4
250° F., ml
250° F. oil	0.0	0.0	0.0	0.0
250° F.	1.2	7.4	4.8	4.4
emulsion
250° F.	0.0	0.0	0.0	0.0
brine
Comments
24 hrs at
75° F.
Total fluid	38	38	38	38
heighth
free oil heighth	0	0	0	0
emusion heighth	38	38	38	38
free brine	0	0	0	0
heighth
free oil, %	0	0	0	0
emusion, %	100%	100%	100%	100%
free brine, %	0	0	0	0
24 hrs at
150° F.
Total fluid	38	38	38	38
heighth
free oil	trace of oil	trace of oil	trace of oil	trace of oil
heighth
emusion	38	38	38	38
heighth
free brine	0	0	0	0
heighth
free oil, %	trace	trace	trace	trace
emusion, %	100%	100%	100%	100%
free brine, %	0	0	0	0
	Sample #
	353	354	359	360
IA - 35, grams	89.26	89.26	84.26	84.26
Cesium Formate,	445 (2.3)	445 (2.3)	445 (2.3)	445 (2.3)
grams
Integrity	25	25	30	30
Emulsifier,
lb/bbl
Integrity	0.5	0.5	0.5	0.5
Synvis,
lb/bbl
Witco DTA	—	0.5	0.5	1.0
350, lb/bbl
Baroid	—	—	10	—
Barablock,
lb/bbl
M-I Lo Wate,	50	50	50	50
lb/bbl
Initial	301	295	384	387	440	492	457	481
ES, volts
Hot-rolled	339	242	306	314	368	389	377	366
16 hrs, ES
Initial Properties	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.
600 rpm	203	155	224	171	300+	300+	261	219
300 rpm	122	92	138	104	253	233	167	142
200 rpm	90	68	103	77	196	182	129	109
100 rpm	53	41	65	47	127	119	84	70
6 rpm	7	7	10	8	28	29	14	12
3 rpm	5	5	7	7	20	22	9	8
Plastic	81	63	86	67	—	—	94	77
Viscosity, cP
Yield Pt,	41	29	52	37	—	—	73	65
lb/100 ft{circumflex over ( )}2
Gels, 10	6/6	5/6	7/8	7/7	19/22	22/26	9/11	8/10
sec/10 min.
Settling in	no	no	no	no	9	10	11	12
thermocup
HR 16 hrs
at 150° F.
600 rpm	212	158	225	167	300+	300+	262	192
300 rpm	131	95	140	102	300+	242	168	123
200 rpm	97	70	105	76	282	186	131	95
100 rpm	60	42	66	47	181	121	86	64
6 rpm	11	8	13	10	42	32	20	14
3 rpm	8	6	10	8	32	26	15	11
Plastic	81	63	85	65	—	—	94	69
Viscosity, cP
Yield Pt,	50	32	55	37	—	—	74	54
lb/100 ft{circumflex over ( )}2
Gels, 10	8/9	6/6	10/10	8/8	32/33	25/27	14/15	10/12
sec/10 min.
API filt,	0.3	1.8	0.0	0.3
ml total
API filt,	—	0.1	0.0	trace
ml oil
API filt,	0.3	1.7	0.0	0.3
ml emulsion
API filt,	—	—	0.0	0.0
ml brine
HTHP at
150° F., ml
HTHP at	4.8	3.6	trace	3.6
250° F., ml
250° F. oil	3.6	0.4	0.0	0.0
250° F.	1.2	3.2	trace	1.6
emulsion
250° F.	0.0	0.0	0.0	2.0
brine
Comments
24 hrs at
75° F.
Total fluid	38	38	38	38
heighth
free oil	0	0	0	0
heighth
emusion	38	38	38	38
heighth
free brine	0	0	0	0
heighth
free oil, %	0	0	0	0
emusion, %	100%	100%	100%	100%
free brine, %	0	0	0	0
24 hrs at
150° F.
Total fluid	38	38	38	38
heighth
free oil	0	0	0	0
heighth
emusion	38	38	38	38
heighth
free brine	0	0	0	0
heighth
free oil, %	0	0	0	0
emusion, %	100%	100%	100%	100%
free brine, %	0	0	0	0
	Sample #
		SA 250	SA 250		SA 250	SA 250
		Initial	Silv.		Initial	Silv.
	349	349.5	349.75	350	350.5	350.75	351	352
IA - 35, grams	94.26	94.26	94.26	94.26	94.26	94.26	94.26	94.26
Cesium Formate,	445	445	445	445	445	445	445	445
grams
Integrity	20	20	20	20	20	20	20	20
Emulsifier,
lb/bbl
Integrity	0.5	0.5	0.5	0.5	0.5	0.5	0.5	0.5
Synvis,
lb/bbl
Witco DTA	—	—	—	0.5	0.5	0.5	0.5	1.0
350, lb/bbl
Baroid	—	—	—	—	—	—	10	—
Barablock,
lb/bbl
M-I Lo Wate,	50	50	50	50	50	50	50	50
lb/bbl
Initial	227			256			301	283
ES, volts
Hot-rolled	109			209			308	262
16 hrs, ES
Static-aged		113			154
ES, volts
Initial Properties	120° F.	120° F.	120° F.	120° F.	120° F.	120° F.	120° F.	120° F.
600 rpm	188	147	—	179	148	—	195	179
300 rpm	113	90	—	108	88	—	117	112
200 rpm	83	68	—	80	65	—	87	84
100 rpm	49	41	—	48	39	—	53	53
6 rpm	8	6	—	6	6	—	7	7
3 rpm	5	4	—	4	4	—	5	4
Plastic	75	57	—	71	60	—	78	67
Viscosity, cP
Yield Pt,	38	33	—	37	28	—	39	45
lb/100 ft{circumflex over ( )}2
Gels, 10	5/6	5/6	—	4/5	4/6	—	5/6	4/5
sec/10 min.
Settling in	no	no	—	no	no	—	no	no
thermocup
HR 16 hrs
at 150° F.
600 rpm	187			196			300+	189
300 rpm	114			120			201	119
200 rpm	85			90			154	91
100 rpm	52			56			98	60
6 rpm	9			9			20	12
3 rpm	7			7			15	8
Plastic	73			76			—	70
Viscosity, cP
Yield Pt,	41			44			—	49
lb/100 ft{circumflex over ( )}2
Gels, 10	7/7			6/8			14/19	8/10
sec/10 min.
Comments
Initial	253			266			300	365
ES, volts
Hot-rolled	205	145	331	222	175	330	348	276
16 hrs, ES
Initial Properties	150° F.			150° F.			150° F.	150° F.
600 rpm	138			134			193	146
300 rpm	81			80			120	92
200 rpm	59			59			91	70
100 rpm	35			35			56	43
6 rpm	6			5			10	6
3 rpm	5			4			7	4
Plastic	57			54			73	54
Viscosity, cP
Yield Pt,	24			26			47	38
lb/100 ft{circumflex over ( )}2
Gels, 10	5/5			4/5			8/9	5/5
sec/10 min.
Settling in	no			no			no	no
thermocup
		SA 250	SA 250		SA 250	SA 250
		Initial	Silv.		Initial	Silv.
HR 16 hrs at 150° F.	150° F.	150° F.	150° F.	150° F.	150° F.	150° F.	150° F.	150° F.
600 rpm	137	98	121	137	104	121	226	143
300 rpm	81	58	70	82	60	70	140	90
200 rpm	60	42	51	61	44	51	106	69
100 rpm	36	25	30	37	26	30	67	44
6 rpm	7	4	5	7	5	5	15	9
3 rpm	5	3	3	5	3	3	11	6
Free Oil, %			22%			25%
	Sample #
		SA 250	SA 250		SA 250	SA 250
		Initial	Silv.		Initial	Silv.
	353	353.5	353.75	354	354.5	354.75	355
IA - 35,	89.26	89.26	89.26	89.26	89.26	89.26	89.26
grams
Cesium	445	445	445	445	445	445	445
Formate,
grams
Integrity	25	25	25	25	25	25	25
Emulsifier,
lb/bbl
Integrity	0.5	0.5	0.5	0.5	0.5	0.5	0.5
Synvis,
lb/bbl
Witco DTA	—	—	—	0.5	0.5	0.5	0.5
350, lb/bbl
Baroid	—	—	—	—	—	—	10
Barablock,
lb/bbl
M-I Lo Wate,	50	50	50	50	50	50	50
lb/bbl
Initial	301			384			357
ES, volts
Hot-rolled	339			306			328
16 hrs, ES
Static-aged		150			240
ES, volts
Initial Properties	120° F.	120° F.	120° F.	120° F.	120° F.	120° F.	120° F.
600 rpm	203	159	—	224	205	—	241
300 rpm	122	97	—	138	125	—	147
200 rpm	90	73	—	103	93	—	111
100 rpm	53	44	—	65	56	—	70
6 rpm	7	7	—	10	9	—	12
3 rpm	5	5	—	7	7	—	8
Plastic	81	62	—	86	80	—	94
Viscosity, cP
Yield Pt,	41	35	—	52	45	—	53
lb/100 ft{circumflex over ( )}2
Gels, 10	6/6	6/7	—	7/8		—	8/10
sec/10 min.
Settling in	no	no	—	no	no	—	1
thermocup
HR 16 hrs
at 150° F.
600 rpm	212			225			300+
300 rpm	131			140			246
200 rpm	97			105			188
100 rpm	60			66			119
6 rpm	11			13			25
3 rpm	8			10			19
Plastic	81			85			—
Viscosity, cP
Yield Pt,	50			55			—
lb/100 ft{circumflex over ( )}2
Gels, 10	8/9			10/10			18/22
sec/10 min.
Comments
Initial	295			387			365
ES, volts
Hot-rolled	242	161	369	314	218	336	325
16 hrs, ES
Initial Properties	150° F.			150° F.			150° F.
600 rpm	155			171			227
300 rpm	92			104			143
200 rpm	68			77			110
100 rpm	41			47			70
6 rpm	7			8			15
3 rpm	5			7			11
Plastic	63			67			84
Viscosity, cP
Yield Pt,	29			37			59
lb/100 ft{circumflex over ( )}2
Gels, 10	5/6			7/7			11/14
sec/10 min.
Settling in	no			no			no
thermocup
		SA 250	SA 250		SA 250	SA 250
		Initial	Silv.		Initial	Silv.
HR 16 hrs at 150° F.	150° F.	150° F.	150° F.	150° F.	150° F.	150° F.	150° F.
600 rpm	158	114	136	167	133	157	274
300 rpm	95	68	80	102	78	94	171
200 rpm	70	50	59	76	57	69	129
100 rpm	42	30	35	47	34	41	81
6 rpm	8	5	7	10	6	6	19
3 rpm	6	4	5	8	4	4	15
Free Oil, %			25%			25%
	Sample #
	356	357	358	359	360
IA - 35, grams	89.26	84.26	84.26	84.26	84.26
Cesium Formate,	445	445	445	445	445
grams
Integrity	25	30	30	30	30
Emulsifier,
lb/bbl
Integrity	0.5	0.5	0.5	0.5	0.5
Synvis, lb/bbl
Witco DTA	1.0	—	0.5	0.5	1.0
350, lb/bbl
Baroid	—	—	—	10	—
Barablock,
lb/bbl
M-I Lo Wate,	50	50	50	50	50
lb/bbl
Initial	329	335	344	440	457
ES, volts
Hot-rolled	307	298	301	368	377
16 hrs, ES
Static-aged
ES, volts
Initial Properties	120° F.	120° F.	120° F.	120° F.	120° F.
600 rpm	196	235	245	300+	261
300 rpm	121	147	150	253	167
200 rpm	92	108	113	196	129
100 rpm	59	67	70	127	84
6 rpm	11	13	13	28	14
3 rpm	8	10	9	20	9
Plastic	75	88	95	—	94
Viscosity, cP
Yield Pt,	46	59	55	—	73
lb/100 ft{circumflex over ( )}2
Gels, 10	8/9	9/10	9/10	19/22	9/11
sec/10 min.
Settling in	3	5	7	9	11
thermocup
HR 16 hrs at
150° F.
600 rpm	201	229	245	300+	262
300 rpm	124	140	151	300+	168
200 rpm	95	105	114	282	131
100 rpm	60	65	70	181	86
6 rpm	12	13	14	42	20
3 rpm	9	10	10	32	15
Plastic	77	89	94	—	94
Viscosity, cP
Yield Pt,	47	51	57	—	74
lb/100 ft{circumflex over ( )}2
Gels, 10	9/10	10/10	10/11	32/33	14/15
sec/10 min.
Comments
Initial	311	316	321	492	481
ES, volts
Hot-rolled	307	301	272	389	366
16 hrs, ES
Initial Properties	150° F.	150° F.	150° F.	150° F.	150° F.
600 rpm	154	182	190	300+	219
300 rpm	95	110	116	233	142
200 rpm	72	82	86	182	109
100 rpm	46	51	53	119	70
6 rpm	10	11	11	29	12
3 rpm	7	8	8	22	8
Plastic	59	72	74	—	77
Viscosity, cP
Yield Pt,	36	38	42	—	65
lb/100 ft{circumflex over ( )}2
Gels, 10	7/8	9/9	8/9	22/26	8/10
sec/10 min.
Settling in	no	no	no	no	no
thermocup
HR 16 hrs
at 150° F.
600 rpm	153	174	185	300+	192
300 rpm	94	106	112	242	123
200 rpm	71	79	84	186	95
100 rpm	49	49	52	121	64
6 rpm	10	12	11	32	14
3 rpm	8	9	8	26	11
Free Oil, %

Cesium formate, IA - 35 (50/50 mixture, 2.3 s.g. CsF)
	Mixing Procedure: 2.3 sg csf
	1.	Measure out IA - 35
	1A.	Add Synvis, mix 5 minutes
	2.	Add CsF, mix 10 min.
	3.	Add Synvert 5, mix 10 minutes
	3A.	Add calcium carbonate, mix 10 minutes
	4.	Run initial ES, viscosities at 120° F.
	5.	Put 10 ml sample in a vial, SA for
		24 hrs at 75° F., measure volumes
	6.	Hot-roll for 16 hours at 150° F.
	7.	Remix, run rheology, ES, API, HTHP at 150° F.
	8.	Put vials in oven and static-age at 150° F.
		for 24 hrs, measure volumes
	9.	If 150° F. HTHP is good, run at 250° F.
41.6/58.4 oil/csf ratio
	Sample #
	337	338	339	340
IA - 35, grams	98.26	98.26	93.26	93.26
Cesium	445	445	445	445
Formate,	(2.366)	(2.366)	(2.366)	(2.366)
grams
Integrity	25	25	20	20
Emulsifier,
lb/bbl
Integrity	0.5	1	0.5	1
Synvis,
lb/bbl
Witco DTA	—	—	—	—
350, lb/bbl
Baroid	50	50	50	50
Baracarb 50,
lb/bbl
Initial	103	129	167	166	114	151	117	128
ES, volts
Hot-rolled	114	102	148	140	139	138	122	118
16 hrs, ES
Initial Properties	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.
600 rpm	162	116	186	118	164	115	183	126
300 rpm	93	65	114	67	96	66	109	73
200 rpm	67	47	83	49	70	48	80	53
100 rpm	40	27	49	29	41	28	47	31
6 rpm	8	7	9	6	7	6	8	6
3 rpm	6	5	7	5	5	5	6	5
Plastic	69	51	72	51	68	49	74	53
Viscosity, cP
Yield Pt,	24	14	42	16	28	17	35	20
lb/100 ft{circumflex over ( )}2
Gels, 10	6/7	6/6	6/7	5/6	5/6	5/5	6/7	5/5
sec/10 min.
Settling in	no	no	no	no	no	no	no	no
thermocup
HR 16 hrs at
150° F.
600 rpm	161	113	187	123	162	114	184	129
300 rpm	93	64	116	70	97	66	111	75
200 rpm	68	46	86	52	72	48	82	55
100 rpm	39	27	52	30	473	28	49	32
6 rpm	8	6	10	6	7	6	8	6
3 rpm	6	5	8	5	5	4	6	5
Plastic	68	49	71	53	65	48	73	56
Viscosity, cP
Yield Pt,	25	15	45	17	32	18	38	28
lb/100 ft{circumflex over ( )}2
Gels, 10	6/6	5/6	7/9	5/6	6/6	5/5	6/7	5/6
sec/10 min.
API filt,	1.0	0.2	0.4	0.3
ml total
API filt,	—	—	—	—
ml oil
API filt,	1.0	0.2	0.4	0.3
ml emulsion
API filt,	—	—	—	—
ml brine
HTHP at			0.2	0.2
150° F., ml
HTHP at			11.4	4.4
250° F., ml
250° F. oil			0.0	0.0
250° F.			6.8	3.2
emulsion
250° F.			4.6	1.2
brine
Comments
41.6/58.4 oil/csf ratio
	Sample #
	347	348	341	342	343	344	345	346
IA - 35,	88.26	88.26	88.26	88.26	98.26	98.26	93.26	93.26
grams
Cesium	445	445	445	445	445	445	445	445
Formate, grams	(2.3)	(2.3)
Integrity	25	25	25	25	15	15	20	20
Emulsifier,
lb/bbl
Integrity	—	—	0.5	1	—	—	—	—
Synvis,
lb/bbl
Witco DTA	0.5	1	—	—	0.5	1	0.5	1
350, lb/bbl
Baroid	50	50	50	50	50	50	50	50
Baracarb 50,
lb/bbl
Initial	212	192	205	243
ES, volts
Hot-rolled	148	145	252	247
16 hrs, ES
Initial Properties	120° F.	150° F.	120° F.	150° F.
600 rpm	177	132	182	132
300 rpm	106	78	111	80
200 rpm	77	57	83	61
100 rpm	46	347	52	38
6 rpm	8	7	10	8
3 rpm	6	5	7	6
Plastic	71	54	71	52
Viscosity, cP
Yield Pt,	35	24	40	28
lb/100 ft{circumflex over ( )}2
Gels, 10	6/6	6/6	8/8	6/7
sec/10 min.
Settling in	no	no	no	no
thermocup
HR 16 hrs at
150° F.
600 rpm	179	140	184	144
300 rpm	109	84	113	88
200 rpm	80	62	85	66
100 rpm	48	37	52	41
6 rpm	8	7	10	9
3 rpm	6	5	8	7
Plastic	70	56	71	56
Viscosity, cP
Yield Pt,	39	32	42	32
lb/100 ft{circumflex over ( )}2
Gels, 10	6/6	5/5	8/8	7/9
sec/10 min.
API filt,	3.5	6.2
ml total
API filt,	—	—
ml oil
API filt,	3.5	6.2
ml emulsion
API filt,	—	—
ml brine
HTHP at	19.4	(0.8
150° F., ml		brine)
HTHP at
250° F., ml
250° F. oil
250° F.
emulsion
250° F.
brine
Comments
NOTE:
1. Sample 337 and 338 looked grainy with 15 lb/bbl Synvert V. Concentration was increased to 25 lb/bbl. After hot-rolling at 150° F., #337 and #338 still appear grainy.
2. Mud weight of 339 is 14.7 lb/gal (CsF in 337-340 is 2.366 s.g)
3. Mud weight of 347 is 14.6 lb/gal (CsF in 347-348 is 2.30 s.g)

Cesium formate, IA - 35 (50/50 mixture)
	175 ml IA - 35 (0.828 sg) - (144.9 grams)
	175 ml Cesium Formate (2.2 sg) - (385 grams)
	Mixing Procedure:
	1.	Measure out IA - 35
	1A.	Add Synvis, mix 5 minutes
	2.	Add CsF, mix 10 min.
	3.	Add Synvert 5, mix 10 minutes
	3A.	Add calcium carbonate, mix 10 minutes
	4.	Run initial ES, viscosities at 120° F.
	5.	Put 10 ml sample in a vial, SA for
		24 hrs at 75° F., measure volumes
	6.	Hot-roll for 16 hours at 150° F.
	7.	Remix, run rheology, ES, API, HTHP at 150° F.
	8.	Put vials in oven and static-age at 150° F.
		for 24 hrs, measure volumes
	9.	If 150° F. HTHP is good, run at 250° F.
50/50 ratio
Mud weight, 13.1 lb/gal
	Sample #
	313	314	314A	314B	315	316	317	318
IA - 35, grams	134.9	134.9	134.9	134.9	134.9	134.9	134.9	134.9
Cesium	385	385	385	385	385	385	385	385
Formate,
grams
Integrity	10	10	15	20	10	10	10	10
Emulsifier,
lb/bbl
Integrity	0.5	0.5	0.5	0.5	0.5	0.5	1	1
Synvis,
lb/bbl
Witco DTA	1	1.25	1.125	1.125	1.5	1.75	1	1.25
350, lb/bbl
Baroid	50	50	50	50	50	50	50	50
Baracarb 50,
lb/bbl
Initial	330	332	353	355	437	402	298	330
ES, volts
Hot-rolled	416	343	284	290	396	427	344	396
16 hrs, ES
Initial
Properties
600 rpm at	89	102	70	72	108	120	91	104
120° F.
300 rpm	58	66	40	39	78	83	59	70
200 rpm	47	53	30	28	66	70	48	57
100 rpm	35	42	19	16	53	56	36	44
6 rpm	20	26	4	2	32	31	20	25
3 rpm	17	21	3	1	26	19	18	22
Plastic	31	36	30	33	30	37	32	34
Viscosity, cP
Yield Pt,	27	30	10	6	48	46	27	36
lb/100 ft{circumflex over ( )}2
Gels, 10	23/19	25/25	4/9	2/3	19/25	19/19	17/23	23/27
sec/10 min.
Settling in	No	No	No	No	No	No	No	No
thermocup
HR 16 hrs at
150° F.
600 rpm at	93	93	82	73	93	95	113	124
120° F.
300 rpm	67	67	54	40	67	69	81	93
200 rpm	57	57	44	29	58	60	69	81
100 rpm	46	47	34	17	48	49	55	67
6 rpm	23	25	14	3	28	27	22	32
3 rpm	17	19	10	2	20	19	18	24
Plastic	26	26	28	33	26	26	32	31
Viscosity, cP
Yield Pt,	41	41	26	7	41	43	49	62
lb/100 ft{circumflex over ( )}2
Gels, 10	19/23	21/21	12/15	3/4	23/23	21/19	21/26	26/21
sec/10 min.
API filt,	1.2	1.8	5.8	2.6	2.2	1.2	0.2	3
ml total
API filt,	0.8	1	0.7	0.6	1	0.2	0.1	0.9
ml oil
API filt,	0.4	0.8	5.1	2.0	1.2	1	0.1	2.1
ml emulsion
API filt,	0	0	0	0	0	0	0	0
ml brine
HTHP at
150° F., ml
HTHP at
250° F., ml
Comments		oil on			oil on	oil on
		top			top	top
		of jar			of jar	of jar
24 hrs at
75° F.
Total fluid	38	38			38	38	38	38
heighth
free oil	0.1	1.0			0.1	0.1	0.1	0.1
heighth
emusion	38	37			38	38	38	38
heighth
free brine	0	0			0	0	0	0
heighth
free oil, %	0.3%	2.6%			0.3%	0.3%	0.3%	0.3%
emusion, %	100.0%	97.4%			100.0%	100.0%	100.0%	100.0%
free brine, %	0.0%	0.0%			0.0%	0.0%	0.0%	0.0%
24 hrs at
150° F.
Total fluid	38	38			38	38	38	38
heighth
free oil	4	4			3	3	2	2
heighth
emusion	34	34			35	35	36	36
heighth
free brine	0	0			0	0	0	0
heighth
free oil, %	10.5%	10.5%			7.9%	7.9%	5.3%	5.3%
emusion, %	89.5%	89.5%			92.1%	92.1%	94.7%	94.7%
free brine, %	0.0%	0.0%			0.0%	0.0%	0.0%	0.0%
72 hrs at
150° F.
Total fluid
heighth
free oil
heighth
emusion
heighth
free brine
heighth
free oil, %
emusion, %
free brine, %
50/50 ratio
Mud weight, 13.1 lb/gal
	Sample #
	319	320	321	322	323	324
IA - 35, grams	134.9	134.9	134.9	134.9	134.9	134.9
Cesium	385	385	385	385	385	385
Formate,
grams
Integrity	10	10	10	10	10	10
Emulsifier,
lb/bbl
Integrity	1	1	1.5	1.5	1.5	1.5
Synvis,
lb/bbl
Witco DTA	1.5	1.75	1	1.25	1.5	1.75
350, lb/bbl
Baroid	50	50	50	50	50	50
Baracarb 50,
lb/bbl
Initial	309	377	245	282	263	358
ES, volts
Hot-rolled	346	355	324	268	380	382
16 hrs, ES
Initial
Properties
600 rpm	115	111	91	117	127	136
at 120° F.
300 rpm	77	78	52	74	85	97
200 rpm	64	64	38	59	70	82
100 rpm	49	49	23	43	54	66
6 rpm	27	27	7	23	30	36
3 rpm	22	22	6	19	24	28
Plastic	38	33	39	43	42	39
Viscosity, cP
Yield Pt,	39	45	13	31	43	58
lb/100 ft{circumflex over ( )}2
Gels, 10	24/24	23/26	7/12	21/26	26/29	29/29
sec/10 min.
Settling	No	No	No	No	No	No
in thermocup
HR 16 hrs at
150° F.
600 rpm	122	118	133	140	147	148
at 120° F.
300 rpm	90	90	98	101	111	111
200 rpm	78	79	83	86	96	97
100 rpm	64	65	68	69	78	78
6 rpm	32	32	28	31	34	34
3 rpm	23	23	22	23	25	25
Plastic	32	28	35	39	36	37
Viscosity, cP
Yield Pt,	58	62	63	62	75	74
lb/100 ft{circumflex over ( )}2
Gels, 10	24/19	21/18	25/31	27/258	26/26	28/26
sec/10 min.
API filt,	2	1.5	2.3	2.4	1.0	0.8
ml total
API filt,	1	1	0.5	0.8	0.3	0.6
ml oil
API filt,	1	0.5	1.8	1.6	0.7	0.2
ml emulsion
API filt,	0	0	0	0	0	0
ml brine
HTHP at
150° F., ml
HTHP at
250° F., ml
Comments	oil on	oil on
	top	top
	of jar	of jar
24 hrs at
75° F.
Total fluid	38	38	38	38	38	38
heighth
free oil	0.1	0.1	1.0	0.1	0.1	0.1
heighth
emusion	38	38	37	38	38	38
heighth
free brine	0	0	0	0	0	0
heighth
free oil, %	0.3%	0.3%	2.6%	0.3%	0.3%	0.3%
emusion, %	100.0%	100.0%	97.4%	100.0%	100.0%	100.0%
free brine, %	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
24 hrs at
150° F.
Total fluid	38	38	38	38	38	38
heighth
free oil	3	2	4	3	2	2
heighth
emusion	35	36	34	35	36	36
heighth
free brine	0	0	0	0	0	0
heighth
free oil, %	7.9%	5.3%	10.5%	7.9%	5.3%	5.3%
emusion, %	92.1%	94.7%	89.5%	92.1%	94.7%	94.7%
free brine, %	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%

Cesium formate, IA - 35 (50/50 mixture)
	175 ml IA - 35 (0.828 sg) - (144.9 grams)
	175 ml Cesium Formate (2.2 sg) - (385 grams)
Mixing Procedure:						529.9	350
		2.2 sg		331.4
		csf
1.	Measure out IA - 35		559.24	8			50	18.52
							13.1080
1A.	Add Synvis, mix 5 minutes		50	18.52			2
2.	Add CsF, mix 10 min.		609.24	350	1.740686			22.5
3.	Add Synvert 5, mix 10 minutes		1.6871					2.70108
				0.373
3A.	Add calcium carbonate, mix 10 minutes		0.828	5	0.309258
				0.626
4.	Run initial ES, viscosities at 120° F.		2.2	5	1.3783
5.	Put 10 ml sample in a vial, SA				1.687558
	for 24 hrs at 75° F., measure volumes
				559.2
6.	Hot-roll for 16 hours at 150° F.		2.3 sg	4	331.48
			csf
7.	Remix, run rheology, ES, API, HTHP at 150° F.			50	18.52
				609.2			14.4999
8.	Put vials in oven and static-age at 150° F.			4	350	1.740686	1
	for 24 hrs, measure volumes			1.687
				1
9.	If 150° F. HTHP is good, run at 250° F.			0.828	0.4163	0.344696
				2.3	0.5837	1.34251
						1.687206
					Additional 0.5 lb/bbl
							137.995
							1	114.26
							193.484	445.015
							9	2
37/63 Oil/Formate ratio 14.4 lb/gal
	Sample #
							H.R. 16 hrs
							at 250° F.
	325	326	327	328	329	329	329	330
IA - 35, grams	87.5	87.5	87.5	87.5	87.5	87.5	87.5	87.5
Cesium	456.9	456.9	456.9	456.9	456.9	456.9	456.9	456.9
Formate,
grams
Integrity	15	15	15	15	15	15	15	15
Emulsifier,
lb/bbl
Integrity	—	1	2	2	1	1	1	—
Synvis,
lb/bbl
Witco DTA	—	1	1	2	—	—	—	1
350, lb/bbl
Baroid	50	50	50	50	50	50	50	50
Baracarb 50,
lb/bbl
Initial	167	395	413	443	303	303		378
ES, volts
Hot-rolled	221	372	377	488	284	284	259	324
16 hrs, ES
Initial Properties							120° F.
600 rpm	163	233	300+	300+	251		247	177
at 120° F.
300 rpm	97	142	210	300+	154		156	106
200 rpm	71	107	162	253	116		121	78
100 rpm	42	64	104	185	71		71	46
6 rpm	6	9	22	66	11		13	5
3 rpm	4	6	16	53	8		10	3
Plastic	66	91	—	—	97		91	71
Viscosity, cP
Yield Pt,	31	51	—	—	57		65	35
lb/100 ft{circumflex over ( )}2
Gels, 10	4/5	6/7	15/18	53/81	7/9		10/18	3/4
sec/10 min.
Settling in								slight
thermocup								sag
HR 16 hrs at 150° F.						150° F.	150° F.
600 rpm	177	267	300+	300+	273	179	165	200
at 120° F.
300 rpm	108	177	260	300+	180	114	101	128
200 rpm	80	137	208	300+	140	87	76	99
100 rpm	48	92	140	252	91	54	46	65
6 rpm	8	21	40	98	20	10	8	15
3 rpm	5	16	32	80	15	7	6	11
Plastic	69	90	—	—	93	65	64	72
Viscosity, cP
Yield Pt,	39	87	—	—	87	49	37	56
lb/100 ft{circumflex over ( )}2
Gels, 10	5/6	15/33	30/57	80/114	14/17	7/8	6/6	10/11
sec/10 min.
API filt,	0.7	0.8	0	0	0			9
ml total
API filt,	0	0	0	0	0			0
ml oil
API filt,	0.7	0.8	0	0	0			9
ml emulsion
API filt,
ml brine
HTHP at
150° F., ml
HTHP at						12.6	7.2
250° F., ml
250° F. oil						0	0
250° F.						11.8	6.4
emulsion
250° F.						0.8	0.8
brine
Comments
24 hrs at
75° F.
Total fluid	39	38	38	38	38			38
heighth
free oil	1.0	0.0	0.0	0.0	0.0			0.0
heighth
emusion	38	38	38	38	38			38
heighth
free brine	0	0	0	0	0			0
heighth
free oil, %
emusion, %
free brine, %
24 hrs at
150° F.
Total fluid
heighth
free oil
heighth
emusion
heighth
free brine
heighth
free oil, %
emusion, %
free brine, %
72 hrs at
150° F.
Total fluid
heighth
free oil
heighth
emusion
heighth
free brine
heighth
free oil, %
emusion, %
free brine, %
37/63 Oil/Formate ratio 14.4 lb/gal
	Sample #
				Hot roll
				16 hrs
				at 250° F.
	331	332	332	332	333	334
IA - 35, grams	82.5	82.5	82.5	82.5	82.5	82.5
Cesium	456.9	456.9	456.9	456.9	456.9	456.9
Formate,
grams
Integrity	20	20	20	20	20	20
Emulsifier,
lb/bbl
Integrity	—	1	1	1	—	0.5
Synvis,
lb/bbl
Witco DTA	1	—	—	—	—	—
350, lb/bbl
Baroid	50	50	50	50	50	50
Baracarb 50,
lb/bbl
Initial	427	285	285		351	337	310	277
ES, volts
Hot-rolled	391	363	363	293
16 hrs, ES
Initial Properties				120° F.	120° F.	150° F.	120° F.	150° F.
600 rpm	223	247		273	218	170	230	170
at 120° F.
300 rpm	137	152		172	132	103	139	103
200 rpm	104	14		131	98	76	104	76
100 rpm	63	69		83	59	46	62	46
6 rpm	9	12		15	8	8	9	8
3 rpm	5	8		11	6	5	6	5
Plastic	86	95		101	86	67	91	67
Viscosity, cP
Yield Pt,	51	57		71	46	36	48	36
lb/100 ft{circumflex over ( )}2
Gels, 10	5/6	8/9		12/15	6/7	6/6	6/7	6/6
sec/10 min.
Settling
in thermocup
HR 16 hrs at 150° F.			150° F.	120° F.	120° F.	150° F.	120° F.	150° F.
600 rpm	223	280	186	174	222	179	245	176
at 120° F.
300 rpm	140	179	117	103	139	112	155	111
200 rpm	106	138	89	76	106	86	119	83
100 rpm	66	89	55	45	67	54	76	52
6 rpm	11	19	11	8	13	11	15	10
3 rpm	7	14	8	6	9	8	10	7
Plastic	83	101	69	71	83	67	90	65
Viscosity, cP
Yield Pt,	57	78	48	32	56	45	65	46
lb/100 ft{circumflex over ( )}2
Gels, 10	7/8	14/18	8/9	6/7	9/10	8/9	10/15	7/8
sec/10 min.
API filt,	3.5	0			1.1	0.3
ml total
API filt,	0	0			0.0	0.0
ml oil
API filt,	3.5	0			1.1	0.3
ml emulsion
API filt,
ml brine
HTHP at
150° F., ml
HTHP at			11.4	9.6	40.0	23.2
250° F., ml
250° F. oil			0	0	0.0	0.0
250° F.			11.4	8.6	36.0	21.2
emulsion
250° F.			0.6	1.0	4.0	2.0
brine
Comments
24 hrs at
75° F.
Total fluid	38	38
heighth
free oil	0.0	0.0
heighth
emusion	38	38
heighth
free brine	0	0
heighth
37/63 Oil/Formate ratio 14.4 lb/gal
	Sample #
	Synvis added after h.r.
	335	336	334A	336A
IA - 35, grams	82.5	82.5	82.5	82.5
Cesium	456.9	456.9	456.9	456.9
Formate,
grams
Integrity	25	25	20	25
Emulsifier,
lb/bbl
Integrity	—	0.5	1.0	1.0
Synvis,
lb/bbl
Witco DTA	—	—	—	—
350, lb/bbl
Baroid	50	50	50	50
Baracarb 50,
lb/bbl
Initial	400	278	337	344	405	297	381	312
ES, volts
Hot-rolled					297	313	312	353
16 hrs, ES
Initial Properties	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.
600 rpm at 120° F.	245	192	264	206	300+	219	300+	227
300 rpm	151	119	162	127	194	135	197	141
200 rpm	114	90	122	96	151	102	150	108
100 rpm	70	56	75	59	96	63	94	68
6 rpm	12	10	14	12	18	12	18	14
3 rpm	8	7	10	9	13	8	13	11
Plastic	94	73	102	79	—	84	—	86
Viscosity, cP
Yield Pt,	57	46	60	48	—	51	—	55
lb/100 ft{circumflex over ( )}2
Gels, 10	8/9	8/9	10/11	9/10	12/16	8/9	13/17	11/11
sec/10 min.
Settling
in thermocup
HR 16 hrs at
150° F.
600 rpm	241	192	264	210	300+	200	297	220
at 120° F.
300 rpm	152	123	169	133	200	127	191	141
200 rpm	116	94	129	103	157	97	148	109
100 rpm	73	60	83	66	104	62	97	70
6 rpm	15	14	18	15	25	13	22	16
3 rpm	11	10	13	11	20	10	17	12
Plastic	89	69	95	77	—	73	106	79
Viscosity, cP
Yield Pt,	63	54	74	56	—	54	85	62
lb/100 ft{circumflex over ( )}2
Gels, 10	11/12	10/11	13/20	11/12	18/24	10/11	16/22	12/13
sec/10 min.
API filt,	1.4	0.2	—	0.2
ml total
API filt,	0.0	0.0	—	0.0
ml oil
API filt,	1.4	0.2	—	0.2
ml emulsion
API filt,
ml brine
HTHP at
150° F., ml
HTHP at	45.6	27.6	12.0	12.0
250° F., ml
250° F. oil	0.0	0.0	0.0	0.0
250° F.	35.6	27.0	10.0	11.0
emulsion
250° F.	10.0	0.6	2.0	1.0
brine
Comments
37/63 Oil/Formate ratio 14.4 lb/gal
	Sample #
			0.5 lb/bbl Synvis
			added after h.r.
	333	334	334A	335
IA - 35, grams	82.5	82.5	82.5	82.5
Cesium	456.9	456.9	456.9	456.9
Formate,
grams
Integrity	20	20	20	25
Emulsifier,
lb/bbl
Integrity	—	0.5	1.0	—
Synvis,
lb/bbl
Witco DTA	—	—	—	—
350, lb/bbl
Baroid	50	50	50	50
Baracarb 50,
lb/bbl
Initial	351	337	310	277	405	297	400	278
ES, volts
Hot-rolled					297	313
16 hrs, ES
Initial Properties	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.	120° F.	150° F.
600 rpm at 120° F.	218	170	230	170	300+	219	245	192
300 rpm	132	103	139	103	194	135	151	119
200 rpm	98	76	104	76	151	102	114	90
100 rpm	59	46	62	46	96	63	70	56
6 rpm	8	8	9	8	18	12	12	10
3 rpm	6	5	6	5	13	8	8	7
Plastic	86	67	91	67	—	84	94	73
Viscosity, cP
Yield Pt,	46	36	48	36	—	51	57	46
lb/100 ft{circumflex over ( )}2
Gels, 10	6/7	6/6	6/7	6/6	12/16	8/9	8/9	8/9
sec/10 min.
Settling
in thermocup
HR 16 hrs at
150° F.
600 rpm	222	179	245	176	300+	200	241	192
at 120° F.
300 rpm	139	112	155	111	200	127	152	123
200 rpm	106	86	119	83	157	97	116	94
100 rpm	67	54	76	52	104	62	73	60
6 rpm	13	11	15	10	25	13	15	14
3 rpm	9	8	10	7	20	10	11	10
Plastic	83	67	90	65	—	73	89	69
Viscosity, cP
Yield Pt,	56	45	65	46	—	54	63	54
lb/100 ft{circumflex over ( )}2
Gels, 10	9/10	8/9	10/15	7/8	18/24	10/11	11/12	10/11
sec/10 min.
API filt,	1.1	0.3	—	1.4
ml total
API filt,	0.0	0.0	—	0.0
ml oil
API filt,	1.1	0.3	—	1.4
ml emulsion
API filt,
ml brine
HTHP at
150° F., ml
HTHP at	40.0	23.2	12.0	45.6
250° F., ml
250° F. oil	0.0	0.0	0.0	0.0
250° F.	36.0	21.2	10.0	35.6
emulsion
250° F.	4.0	2.0	2.0	10.0
brine
37/63 Oil/Formate ratio 14.4 lb/gal
	Sample #
			0.5 lb/bbl Synvis
			added after h.r.
	336		336A
IA - 35, grams	82.5	82.5
Cesium	456.9	456.9
Formate,
grams
Integrity	25	25
Emulsifier,
lb/bbl
Integrity	0.5	1.0
Synvis,
lb/bbl
Witco DTA	—	—
350, lb/bbl
Baroid	50	50
Baracarb 50,
lb/bbl
Initial	337	344	381	312
ES, volts
Hot-rolled			312	353
16 hrs, ES
Initial Properties	120° F.	150° F.	120° F.	150° F.
600 rpm at 120° F.	264	206	300+	227
300 rpm	162	127	197	141
200 rpm	122	96	150	108
100 rpm	75	59	94	68
6 rpm	14	12	18	14
3 rpm	10	9	13	11
Plastic	102	79	—	86
Viscosity, cP
Yield Pt,	60	48	—	55
lb/100 ft{circumflex over ( )}2
Gels, 10	10/11	9/10	13/17	11/11
sec/10 min.
Settling in
thermocup
HR 16 hrs
at 150° F.
600 rpm	264	210	297	220
at 120° F.
300 rpm	169	133	191	141
200 rpm	129	103	148	109
100 rpm	83	66	97	70
6 rpm	18	15	22	16
3 rpm	13	11	17	12
Plastic	95	77	106	79
Viscosity, cP
Yield Pt,	74	56	85	62
lb/100 ft{circumflex over ( )}2
Gels, 10	13/20	11/12	16/22	12/13
sec/10 min.
API filt,	0.2	0.2
ml total
API filt,	0.0	0.0
ml oil
API filt,	0.2	0.2
ml emulsion
API filt,
ml brine
HTHP at
150° F., ml
HTHP at	27.6	12.0
250° F., ml
250° F. oil	0.0	0.0
250° F.	27.0	11.0
emulsion
250° F.	0.6	1.0
brine
Comments

Cesium formate, Escaid 110 (50/50 mixture)
175 ml Escaid 110 (0.803 sg) - (140.5 grams)
175 ml Cesium Formate (2.2 sg) - (385 grams)
Mixing Procedure:
1.	Measure out Escaid 110
2.	Add emulsifiers, mix 5 minutes
3.	Add CsF, mix 10 min. on HB, mix on Silverson to 135° F.
3A.	Add Lo-Wate, mix 10 min. on HB
4.	Run initial ES, viscosities at 120° F.
5.	Put 10 ml sample in a vial, SA for 24 hrs at
	75° F., measure volumes
6.	Hot-roll for 16 hours at 150° F.
7.	Remix, run rheology, ES, API, HTHP at 150° F.
8.	Put vials in oven and static-age at 150° F.
	for 24 hrs, measure volumes
9.	If 150° F. HTHP is good, run at 250° F.
	Sample #
	273	274	275	276	277	278
Integrity Synvert	5	10	10	10	15	15
IV (Lot# 000329),
lb/bbl
Witco AX-180-2,	5	5	5	5	5	5
lb/bbl
Witco DTA			2	3		2
350, lb/bbl
dimer trimer
Baroid	50	50	50	50	50	50
Baracarb 50,
lb/bbl
Initial	363	360	425	572	454	417
ES, volts @ 120° F.
Hot-rolled 16 hrs. ES	399	410	378	489	403	329
Jar − S = Settling,	S 3	S 3	S	S 3	S	S
3 = 3 Phases, N = No
Initial
Properties
600 rpm at 120° F.	24	25	29	42	27	29
300 rpm	13	14	17	30	15	15
200 rpm	9	9	12	25	10	11
100 rpm	5	5	8	19	6	6
6 rpm	1	1	2	10	2	1
3 rpm	1	1	1	7	1	1
Plastic	11	11	12	12	12	14
Viscosity, cP
Yield Pt,lb/100 ft{circumflex over ( )}2	2	3	5	18	3	1
Gels, 10	1/1	1/1	2/2	7/8	1/2	1/1
sec/10 min.
Settling in	Y	Y	Y	N	Y	Y
thermocup
HR 64 hrs at
150° F.
600 rpm at 120° F.	24	26	31	54	28	28
300 rpm	12	13	18	40	15	15
200 rpm	8	9	14	34	11	11
100 rpm	5	5	9	28	7	6
6 rpm	1	1	3	19	2	1
3 rpm	1	1	2	11	2	1
Plastic	12	13	13	14	13	13
Viscosity, cP
Yield Pt,	0	0	5	26	2	2
lb/100 ft{circumflex over ( )}2
Gels, 10	1/1	1/1	2/2	14/8	2/2	1/1
sec/10 min.
Settling in	Y	Y	N	N	Y	Y
Thermocup
Settling in Jar	¼″	⅛″	{fraction (1/16)}″	—	{fraction (1/16)}″	⅛″
API filt,	3.2	1.8	2.0	2.0	1.4	2.6
ml total
API filt,	1.6	1.6	2.0	2.0	0.4	2.6
ml oil
API filt,	1.6	0.2	0.0	0.0	1.0	0.0
ml brine
HTHP at 150° F., ml	8.6	6.6	8.6	8.0	9.8	13.4
HTHP at 250° F., ml		17.2		29.0
Static Age - 64 hrs
at 75° F.
Total fluid height	32	32	32	32	32	32
free oil height	4	3	7	7	2	3
emusion height	28	29	25	25	30	29
free brine height	0	0	0	0	0	0
free oil, %	13%	9%	22%	22%	6%
9%
emusion, %	87.5%	90.6%	78.1%	78.1%	93.8%	90.6%
free brine, %	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
Total	100%	100%	100%	100%	100%	100%
MP = Multiple	MP	MP	MP	MP	MP	MP
Phase Emulsion
Static Age - 24
hrs at 150° F.
Total fluid height	32	32	32	32	32	32
free oil height	7	7	10	8	10	9
emusion height	25	25	22	24	22	23
free brine height	0	0	0	0	0	0
free oil, %	22%	22%	31%	25%	31%	28%
emusion, %	78.1%	78.1%	68.8%	75.0%	68.8%	71.9%
free brine, %	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
Total	100%	100%	100%	100%	100%	100%
MP = Multiple	MP	MP	MP	MP	MP	MP
Phase Emulsion
Difference (64 hrs/24
hrs at 150° F.)
free oil, %
emusion, %
free brine, %
	Sample #
	279	280	281	282	283	284
Integrity Synvert IV	5	5	5	5	2.5	2.5
(Lot# 000329), lb/bbl
Witco AX-180-2, lb/bbl	7.5	10	10	10	10	10
Witco DTA			2	3		2
350, lb/bbl
dimer trimer
Baroid	50	50	50	50	50	50
Baracarb 50,
lb/bbl
Initial	448	390	445	552	360	458
ES, volts @ 120° F.
Hot-rolled	398	431	345	288	359	229
16 hrs, ES
Jar − S = Settling,	S	S	N	N	S	S
3 = 3 Phases, N = No
Initial
Properties
600 rpm at 120° F.	26	24	30	47	24	32
300 rpm	14	13	18	33	13	19
200 rpm	9	9	13	28	9	15
100 rpm	5	5	9	21	5	10
6 rpm	1	1	3	9	2	3
3 rpm	1	1	3	6	1	2
Plastic	12	11	12	14	11	13
Viscosity, cP
Yield Pt,	2	2	6	19	2	6
lb/100 ft{circumflex over ( )}2
Gels, 10	1/2	1/2	3/4	6/6	1/2	3/3
sec/10 min.
Settling in	Y	Y	Y	N	Y	N
thermocup
HR 64 hrs
at 150° F.
600 rpm at 120° F.	25	25	32	56	25	35
300 rpm	13	13	20	42	13	22
200 rpm	9	9	16	36	9	13
100 rpm	5	5	11	28	5	12
6 rpm	1	1	4	15	1	4
3 rpm	1	1	3	8	1	4
Plastic	12	12	12	14	12	13
Viscosity, cP
Yield Pt,	1	1	8	28	1	9
lb/100 ft{circumflex over ( )}2
Gels, 10	1/1	1/1	4/5	7/5	2/2	5/3
sec/10 min.
Settling in	Y	Y	Y	N	Y	N
Thermocup
Settling in Jar	¼″	¼″	—	¼″	{fraction (5/16)}″	—
API filt,	3.0	3.2	2.0	2.1	2.1	2.2
ml total
API filt,	0.8	1.2	1.8	1.8	1.4	1.9
ml oil
API filt,	2.2	2.0	0.2	0.2	0.7	0.3
ml brine
HTHP at 150° F., ml	11.6	14.6	7.0	4.4	12.0	5.6
HTHP at 250° F., ml			15.0	12.4	20.8	14.8
Static Age - 64 hrs
at 75° F.
Total fluid height	32	32	32	32	32	32
free oil height	3	8	9	10	9	9
emusion height	29	24	23	22	23	23
free brine height	0	0	0	0	0	0
free oil, %	9%	25%	28%	31%	28%	28%
emusion, %	90.6%	75.0%	71.9%	68.8%	71.9%	71.9%
free brine, %	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
Total	100%	100%	100%	100%	100%	100%
MP = Multiple	MP	—	—	—	—	—
Phase Emulsion
Static Age - 24 hrs
at 150° F.
Total fluid height	32	32	32	32	32	32
free oil height	4	10	10	10	10	10
emusion height	28	22	22	22	22	22
free brine height	0	0	0	0	0	0
free oil, %	13%	31%	31%	31%	31%	31%
emusion, %	87.5%	68.8%	68.8%	68.8%	68.8%	68.8%
free brine, %	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
Total	100%	100%	100%	100%	100%	100%
MP = Multiple	MP	—	—	—	—	—
Phase Emulsion
Difference (64 hrs/24
hrs at 150° F.)
free oil, %
emusion, %
free brine, %

Cesium formate, IA - 35 (50/50 mixture)
175 ml IA - 35 (0.828 sg) - (144.9 grams)	NOTE: Make up ½ bbl
175 ml Cesium Formate (2.2 sg) - (385 grams)	Equivalents
Mixing Procedure:
1.	Measure out IA - 35
1A.	Add Synvis, mix 5 minutes
2.	Add CsF, mix 10 min.
3.	Add Synvert 5, mix 10 minutes
3A.	Add calcium carbonate, mix 10 minutes
4.	Run initial ES, viscosities at 120° F.
5.	Put 10 ml sample in a vial, SA for
	24 hrs at 75° F., measure volumes
6.	Hot-roll for 16 hours at 150° F.	NOTE: Make up ½ bbl
		Equivalents
7.	Remix, run rheology, ES, API, HTHP at 150° F.
8.	Put vials in oven and static-age at 150° F.
	for 24 hrs, measure volumes
9.	If 150° F. HTHP is good, run at 250° F.	NOTE: Make up ½ bbl
		Equivalents
	oil/cs ratio
	50/50		50/50	50/50		50/50	53/47
	Sample #
	285	285	286	287	287	288	289
IA - 35, grams	119.9	119.9	119.9	119.9	119.9	119.9	144.9
Cesium	385	385	385	385	385	385	385
Formate,
grams
Integrity Synvert	25	25	25	25	25	25	25
5, lb/bbl
Integrity	5	5	5	10	10	10	5
Synvis,
lb/bbl
Baroid	—	—	50	—	—	50	—
Baracarb 50,
lb/bbl
Initial	823		680	646		595	641
ES, volts
Hot-rolled	494		619	551		528	509
16 hrs, ES
Initial
Properties
600 rpm at	273	164	300+	300+	300+	300+	142
120° F.
300 rpm	184	94	230	300+	290	300+	85
200 rpm	144	67	182	300+	230	300+	64
100 rpm	102	39	130	229	157	300+	40
6 rpm	39	7	41	81	45	119	10
3 rpm	26	5	37	72	38	105	8
Plastic	89	70	—	—		—	57
Viscosity, cP
Yield Pt,	95	24	—	—		—	28
lb/100 ft{circumflex over ( )}2
Gels, 10	23/27	5/7	33/37	65/72	35/42	87/96	7/9
sec/10 min.
Settling in	N		N	N		N	N
thermocup
API filt,	10 (8 min)		0	1.5		0	10 (2 min)
ml total
API filt,	0		0	0		0	0
ml oil
API filt,	0		0	0		0	0
ml brine
HTHP at 150° F., ml
HTHP at 250° F., ml
HR 16 hrs at
150° F.
600 rpm at 120° F.	270		294	300+		300+	197
300 rpm	171		184	300+		300+	120
200 rpm	132		148	300+		300+	90
100 rpm	89		100	300+		284	60
6 rpm	24		28	102		95	16
3 rpm	19		23	87		83	13
Plastic	99		110	—		—	77
Viscosity, cP
Yield Pt,	72		74	—		—	43
lb/100 ft{circumflex over ( )}2
Gels, 10	16/21		21/25	81/86		74/84	11/16
sec/10 min.
Comments
24 hrs at
75° F.
Total fluid	33		34	34		33	34
heighth
free oil	0		0	0		0	0
heighth
emusion	33		34	34		33	34
heighth
free brine	0		0	0		0	0
heighth
free oil, %	0%		0%	0%		0%	0%
emusion, %	100.0%		100.0%	100.0%		100.0%	100.0%
free brine, %	0.0%		0.0%	0.0%		0.0%	0.0%
24 hrs at
150° F.
Total fluid	33		34	34		33	34
heighth
free oil	0		0	0		0	0
heighth
emusion	33		34	34		33	34
heighth
free brine	0		0	0		0	0
heighth
free oil, %	0%		0%	0%		0%	0%
emusion, %	100.0%		100.0%	100.0%		100.0%	100.0%
free brine, %	0.0%		0.0%	0.0%		0.0%	0.0%
72 hrs at
150° F.
Total fluid	33		34	34		33	34
heighth
free oil	1		2	0		0	2
heighth
emusion	32		32	34		33	32
heighth
free brine	0		0	0		0	0
heighth
free oil, %	3%		6%	0%		0%	6%
emusion, %	97.0%		94.1%	100.0%		100.0%	94.1%
free brine, %	0.0%		0.0%	0.0%		0.0%	0.0%
API filt,
ml total
API filt,
ml oil
API filt,
ml brine
HTHP at 150° F., ml
HTHP at 250° F., ml
HR 16 hrs at
150° F.
600 rpm at 120° F.	292						200
300 rpm	192						124
200 rpm	151						94
100 rpm	102						59
6 rpm	31						14
3 rpm	25						11
Plastic	100						76
Viscosity, cP
Yield Pt,	92						48
lb/100 ft{circumflex over ( )}2
Gels, 10	23/26						10/12
sec/10 min.
Comments
oil/cs ratio
	53/47	48.5/51.5	48.5/51.5	48.5/51.5	48.5/51.5	56/44	56/44
	Sample #
	290	291	292	293	294	295	296
IA - 35, grams	144.9	94.9	94.9	94.9	94.9	144.9	144.9
Cesium	385	385	385	385	385	385	385
Formate,
grams
Integrity Synvert	25	50	50	50	50	50	50
5, lb/bbl
Integrity	10	5	5	10	10	5	10
Synvis,
lb/bbl
Baroid	—	—	50	—	50	—	—
Baracarb 50,
lb/bbl
Initial	1032	452	392	409	337	651	698
ES, volts
Hot-rolled	660	469	442	373	341	490	645
16 hrs, ES
Initial
Properties
600 rpm at 120° F.	300+	262	300+	300+	300+	114	300+
300 rpm	300+	164	193	300+	300+	68	230
200 rpm	287	129	149	300+	300+	50	184
100 rpm	243	86	100	300+	221	33	126
6 rpm	83	24	28	115	73	11	38
3 rpm	73	19	22	98	61	9	31
Plastic	—	98	—	—	—	46	—
Viscosity, cP
Yield Pt,	—	66	—	—	—	22	—
lb/100 ft{circumflex over ( )}2
Gels, 10	64/69	19/25	21/28	89/103	57/76	4/4	29/36
sec/10 min.
Settling in	N	N	N	N	N	N	N
thermocup
API filt,	1.5	10 (2	0.0	7.0	0.0	6.9	10 (2
ml total		min)					min)
API filt,	0	0	0	0	0	0	0
ml oil
API filt,	0	0	0	0	0	0	0
ml brine
HTHP at 150° F., ml
HTHP at 250° F., ml
HR 16 hrs at
150° F.
600 rpm at 120° F.	300+	300+	300+	300+	300+	152	300+
300 rpm	300+	206	257	300+	300+	89	203
200 rpm	243	160	202	300+	300+	65	155
100 rpm	177	109	140	263	298	41	106
6 rpm	69	33	43	89	100	11	32
3 rpm	59	29	36	78	88	9	27
Plastic	—	—	—	—	—	63	—
Viscosity, cP
Yield Pt,	—	—	—	—	—	26	—
lb/100 ft{circumflex over ( )}2
Gels, 10	46/53	24/33	33/42	70/80	78/88	3/4	25/32
sec/10 min.
Comments
24 hrs at
75° F.
Total fluid	34	35	34	33	33	34	34
heighth
free oil	0	0	0	0	0	0	0
heighth
emusion	34	35	34	33	33	34	34
heighth
free brine	0	0	0	0	0	0	0
heighth
free oil, %	0%	0%	0%	0%	0%	0%	0%
emusion, %	100.0%	100.0%	100.0%	100.0%	100.0%	100.0%	100.0%
free brine, %	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
24 hrs at
150° F.
Total fluid	34	35	34	33	33	34	34
heighth
free oil	0	0	1	0	0	1	0
heighth
emusion	34	35	33	33	33	33	34
heighth
free brine	0	0	0	0	0	0	0
heighth
free oil, %	0%	0%	3%	0%	0%	3%	0%
emusion, %	100.0%	100.0%	97.1%	100.0%	100.0%	97.1%	100.0%
free brine, %	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
72 hrs at
150° F.
Total fluid	34	35	34	33	33	34	34
heighth
free oil	0	2	2	0	0	5	0
heighth
emusion	34	33	32	33	33	29	34
heighth
free brine	0	0	0	0	0	0	0
heighth
free oil, %	0%	6%	6%	0%	0%	15%	0%
emusion, %	100.0%	94.3%	94.1%	100.0%	100.0%	85.3%	100.0%
free brine, %	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%	0.0%
HR 16 hrs at
150° F.
600 rpm at		300+				144
120° F.
300 rpm		240				83
200 rpm		189				61
100 rpm		129				38
6 rpm		41				9
3 rpm		34				7
Plastic						61
Viscosity, cP
Yield Pt,		—				22
lb/100 ft{circumflex over ( )}2
Gels, 10		32/38				7/9
sec/10 min.
Comments

Cesium formate, Escaid 110 (50/50 mixture)
	175 ml Escaid 110 (0.803 sg) - (140.5 grams)
	175 ml Cesium Formate (2.2 sg) - (385 grams)
	Mixing Procedure:
	1.	Measure out Escaid 110
	2.	Add emulsifiers, mix 5 minutes, add Barablock,
		mix 10 minutes
	3.	Add CsF, mix 10 min. on HB, mix on Silverson
		to 135° F.
	3A.	Add Lo-Wate, mix 10 min. on HB
	4.	Run initial ES, viscosities at 120° F.
	5.	Put 10 ml sample in a vial, SA for 24 hrs at
		75° F., measure volumes
	6.	Hot-roll for 16 hours all 50° F.
	7.	Remix, run rheology, ES, API, HTHP at 150° F.
	8.	Put vials in oven and static-age at 150° F.
		for 24 hrs, measure volumes
	9.	If 150° F. HTHP is good, run at 250° F.
	Sample #
	261	262	262	264	265	266
Integrity	10	15	20	15
Synvert IV (Lot #
000329), lb/bbl
Rhodia Miranol					7	10.5
CS, lb/bbl
Witco AX-180-2,
lb/bbl
Witco DTA				3
350, lb/bbl
dimer trimer
Baroid	50	50	50	50	50	50
Baracarb 50,
lb/bbl
Initial	285	306	355	327	8	1
ES, volts
Hot-rolled	320	350	314	376	2	1
16 hrs, ES
Initial
Properties
600 rpm at 120° F.	26	25	25	27	64	66
300 rpm	13	12	13	13	40	41
200 rpm	9	8	9	8	32	32
100 rpm	5	4	4	4	22	23
6 rpm	1	1	1	0	7	8
3 rpm	1	1	1	0	4	5
Plastic	13	13	12	14	24	25
Viscosity, cP
Yield Pt,lb/100 ft{circumflex over ( )}2	0	−1	1	−1	16	16
Gels, 10	0/1	0/1	1/1	1/1	6/4	6/5
sec/10 min.
Settling in	yes	yes	yes	yes	no	no
thermocup
API filt,	4.8	4.1	2.7	2.7	11 (1 min)	10 (1 min)
ml total
API filt,	—	—	—	—	—	—
ml oil
API filt,	—	—	—	—	4.2	7.0
ml brine
HR 16 hrs at
150° F.
600 rpm at 120° F.	26	26	27	42	63	54
300 rpm	14	13	14	25	40	34
200 rpm	9	8	9	20	31	28
100 rpm	5	5	5	14	19	20
6 rpm	1	1	1	3	6	6
3 rpm	1	1	1	3	4	3
Plastic	12	13	13	17	23	20
Viscosity, cP
Yield Pt,	2	0	1	8	17	14
lb/100 ft{circumflex over ( )}2
Gels, 10	1/1	1/1	1/1	1/1	4/5	5/4
sec/10 min.
Comments	settling	settling	settling	¼	3	3
				inch oil	phases	phases
24 hrs at
75° F.
Total fluid	32	33	33	32	32	32
heighth
free oil	2	2	2	2	0	0
heighth
emusion	28	29	29	30	21	21
heighth
free brine	0	0	0	0	11	11
heighth
free oil, %	6%	6%	6%	6%	0%	0%
emusion, %	87.5%	87.9%	87.9%	93.8%	65.6%	65.6%
free brine, %	0.0%	0.0%	0.0%	0.0%	34.4%	34.4%
24 hrs at
150° F.
Total fluid	32	33	33	32	32	32
heighth
free oil	2	4	3	5	0	0
heighth
emusion	30	29	30	27	21	20
heighth
free brine	0	0	0	0	11	12
heighth
free oil, %	6%	12%	9%	16%	0%	0%
emusion, %	93.8%	87.9%	90.9%	84.4%	65.6%	62.5%
free brine, %	0.0%	0.0%	0.0%	0.0%	34.4%	37.5%
Difference (72 hrs/24
hrs at 150° F.)
free oil, %	0%	6%	3%	9%	0%	0%
emusion, %	6%	0%	3%	−9%	0%	−3%
free brine, %	0%	0%	0%	0%	0%	3%
	Sample #
	267	268	269	270	271	272
Integrity
Synvert IV (Lot#
000329), lb/bbl
Rhodia Miranol	14	10.5
CS, lb/bbl
Witco AX-180-2,			7	10.5	14	10.5
lb/bbl
Witco DTA		3				3
350, lb/bbl
dimer trimer
Baroid	50	50	50	50	50	50
Baracarb 50,
lb/bbl
Initial	1	37	151	318	349	345
ES, volts
Hot-rolled	0	18	175	351	419	321
16 hrs, ES
Initial
Properties
600 rpm at 120° F.	66	67	30	24	25	94
300 rpm	42	47	17	13	13	70
200 rpm	34	50	13	9	9	59
100 rpm	24	31	8	6	6	46
6 rpm	8	2	2	1	1	15
3 rpm	4	2	2	1	1	6
Plastic	24	20	13	11	12	24
Viscosity, cP
Yield Pt,	18	27	4	2	1	46
lb/100 ft{circumflex over ( )}2
Gels, 10	6/4	5/12	2/3	1/1	1/1	9/7
sec/10 min.
Settling in	no	no	no	yes	yes	no
thermocup
API filt,	10 (1 min)	1.9	2.6	1/1	0.9	0.4
ml total
API filt,	—	0.6	—	—	—	—
ml oil
API filt,	2.5	0.3	—	—	—	—
ml brine
HR 16 hrs at
150° F.
600 rpm at	62	67	33	28	28	79
120° F.
300 rpm	39	42	19	16	16	61
200 rpm	32	37	15	12	11	53
100 rpm	22	26	10	8	7	42
6 rpm	7	2	3	2	2	16
3 rpm	4	2	2	2	2	7
Plastic	23	25	14	12	12	18
Viscosity, cP
Yield Pt,	16	17	5	4	4	43
lb/100 ft{circumflex over ( )}2
Gels, 10	6/5	2/9	3/4	3/3	2/2	9/6
sec/10 min.
Comments	3 phases	2 phases	sagging	sagging	sagging	⅜ inch oil
24 hrs at
75° F.
Total fluid	32	32	32	32	32	32
heighth
free oil	0	12	4	4	4	5
heighth
emusion	23	20	28	28	28	27
heighth
free brine	9	0	0	0	0	0
heighth
free oil, %	0%	38%	13%	13%	13%	16%
emusion, %	71.9%	62.5%	87.5%	87.5%	87.5%	84.4%
free brine, %	28.1%	0.0%	0.0%	0.0%	0.0%	0.0%
24 hrs at 150° F.
Total fluid	32	32	32	32	32	32
heighth
free oil	0	12	7	5	5	12
heighth
emusion	22	20	25	27	27	20
heighth
free brine	10	0	0	0	0	0
heighth
free oil, %	0%	38%	22%	16%	16%	38%
emusion, %	68.8%	62.5%	78.1%	84.4%	84.4%	62.5%
free brine, %	31.3%	0.0%	0.0%	0.0%	0.0%	0.0%
Difference (72 hrs/24
hrs at 150° F.)
free oil, %	0%	0%	9%	3%	3%	22%
emusion, %	−3%	0%	−9%	−3%	−3%	−22%
free brine, %	3%	0%	0%	0%	0%	0%

Other embodiments of the present invention will be apparent to those skilled in the art from consideration of the present specification and practice of the present invention disclosed herein. It is intended that the present specification and examples be considered as exemplary only with a true scope and spirit of the invention being indicated by the following claims and equivalents thereof.

Claims

1. A drilling fluid or mud comprising at least one alkali metal formate or monovalent carboxylic salt and at least one emulsifier and at least one sealing or fluid loss additive and at least one hydrocarbon-based fluid, wherein the at least one hydrocarbon-based fluid is partially or totally emulsified into an aqueous fluid containing the at least one alkali metal formate or monovalent carboxylic salt.

2. A drilling fluid comprising at least one alkali metal formate and at least one emulsifier, and at least one sealing or fluid loss additive and at least one hydrocarbon-based fluid.

3. The drilling fluid of claim 2, further comprising at least one synthetic mud fluid.

4. The drilling fluid of claim 2, wherein said alkali metal formate comprises potassium formate.

5. The drilling fluid of claim 2, wherein said drilling fluid further comprises at least one acid.

6. The drilling fluid of claim 2, further comprising at least one solid weighting material, at least one wetting agent, at least one organo clay, at least one filtration control agent, at least one polymer, or combinations thereof.

7. The drilling fluid of claim 2, wherein said emulsifier comprises a dimer trimer acid, imadazoline, tall oil, or combinations thereof.

8. The drilling fluid of claim 2, wherein said hydrocarbon-based fluid comprises diesel oil.

9. The drilling fluid of claim 2, wherein said hydrocarbon-based fluid comprises at least one synthetic oil.

10. The drilling fluid of claim 5, wherein said acid is formic acid or an acid derivative thereof.

11. The drilling fluid of claim 1, wherein said alkali metal formate is less than fully saturated in said drilling fluid.

12. A method to drill a well comprising drilling said well in the presence of the drilling fluid of claim 1.

13. A method to drill a well comprising drilling said well in the presence of the drilling fluid of claim 2.

14. A method to reduce the solids content in a drilling fluid comprising substituting at least a portion of said solid weighting material with an aqueous solution comprising the drilling fluid of claim 2.

15. A drilling fluid or mud made by mixing at least one alkali metal formate and at least one emulsifier and at least one sealing or fluid loss additive and at least one hydrocarbon-based fluid.

16. The drilling fluid or mud of claim 1, wherein said drilling fluid or mud is a mixture of hydrocarbon-based fluid and aqueous-based solution present at a ratio of 65% by volume hydrocarbon fluid: 35% aqueous-based solution to 1% by volume hydrocarbon fluid: 99% by volume aqueous based solution.

17. The drilling fluid of claim 2, wherein said drilling fluid is a hydrocarbon-water emulsion.

18. The drilling fluid of claim 2, wherein said drilling fluid is a mixture of hydrocarbon-based fluid and aqueous-based solution present at a ratio of 65% by volume hydrocarbon fluid: 35% aqueous-based solution to 1% by volume hydrocarbon fluid: 99% by volume aqueous based solution.

19. The drilling fluid or mud of claim 1, wherein no solid weighting material is present.

20. The drilling fluid of claim 2, wherein no solid weighting material is present.

21. The drilling fluid of claim 2, wherein the at least one alkali metal formate is partially or totally emulsified into the hydrocarbon-based fluid.

22. The drilling fluid of claim 2, wherein the at least one hydrocarbon-based fluid is partially or totally emulsified into an aqueous fluid containing the at least one alkali metal formate.