Commercial Oil Production Research Articles

Exploration and Development High-Lights in Denver Basin: ABSTRACT

A resurgence of industry interest in Denver basin oil and gas prospects has been reflected by a 30 per cent increase in the number of wells completed in western Nebraska during 1965. Eastern Colorado drilling activity has shown decline of less than 10 per cent compared with 1964. Any significant increase in the number of wells drilled ultimately will reverse the continuing decline of oil and gas production. Exploratory drilling to the shallow. Cretaceous D and J Sandstone objectives was well dispersed throughout the basin and resulted in the discovery of many commercial, though no truly significant, fields. The 11-well Stage Hill field on the Scotts Bluff-Banner County line is representative, both geologically and economically, of the better structural-stratigraphic type oil accumulations discovered in western Nebraska. The Moccasin field of eastern Adams County is typical of the small, though profitable, structural-stratigraphic J Sandstone oil accumulations discovered in eastern Colorado. Several exploratory tests to pre-Cretaceous objectives on the western flank of the Chadron arch and in extreme northwestern Nebraska were unsuccessful. Encouragement in searching for pre-Cretaceous oil and gas production on the fringes of the Denver basin in Colorado was afforded by a gas discovery in the Pennsylvanian Morrow Sandstone, Kit Carson County, and an oil discovery in the Mississippian Osage, northern Prowers County. The gas discovery is high on the eastern flank of the basin and appears to be a stratigraphic accumulation trapped in lenticular Morrow sandstones. A unique feature of this Morrow gas is its high helium content--more than 4 per cent. The Comanche field discovery of oil in Mississippian Osage carbonates is the first indication of commercial oil production in the Mississippian in eastern Colorado. This discovery, even though it is located in the Hugoton embayment of the Anadarko basin, suggests that Mississippian carbonates may be prospective for oil and gas throughout much of the eastern flank of the Denver basin. The Comanche field appears to be primarily a structural accumulation on the western, or upthrown, side of a major northeast-trending fault zone. Seismic activity and exploratory drilling to the Permian Lyons Sandstone and Big Blue carbonate objectives in the deeper part of the basin have increased during 1965. The increased interest in pre-Cretaceous objectives, combined with a continuing search for new Cretaceous D and J Sandstone fields, should maintain a relatively high level of exploratory activity during the coming year. End_of_Article - Last_Page 1568------------

Petroleum Developments in North Africa in 1964

Oil production in the 6 North African nations of Morocco, Algeria, Tunisia, Libya, Egypt, and Sudan which are covered in this report reached a new high of 561,802,211 bbls. in 1964. This was an increase of 178.2 million bbls., approximately 33%, over 1963 figures. With a gain of more than 114 million bbls. over 1963. Libya was the major contributor to the increased flow of oil. In Algeria the gain was 14.7 million bbls and in Egypt 5.2 million bbls. In Morocco oil production decreased from 1.1 million to 0.9 million bbls. Tunisia and Sudan had not yet established commercial oil production. Gas production increased 17.6 billion cu. ft., largely the result of a gain of 14.7 billion cu. ft. in Algeria as the export of liquified natural gas began. Figure 1 shows the surface geology of North Africa and the distribution of the sedimentary basins. Figure 2 is a plot of exploratory activity for the past 10 years which shows the time relationship of reconnaissance exploratory work compared with rig activity. Increased activity in Egypt resulting from new concession contracts in late 1963 and early 1964 caused a slight increase in gravity and magnetic work over 1963. All other exploratory activity continued a decline that will probably persist through 1965. Exploratory completions, total footage drilled, and total production in North Africa are compared in Figure 3. The implication that the plotted number of wells and footage drilled were required to establish the production attained is somewhat misleading. In all probability the present rate of production could have been attained with less drilling activity but concession terms requiring periodic surrenders have prompted the maintenance of active drilling programs to evaluate acreage. Oil production should continue to increase in Algeria, Egypt, and Libya in 1965. The Tunisian discovery at El Borma is still being evaluated and no target date for initiating production has been announced.

Commercial Oil Production in Australia

Commercial Oil Production in Australia

Oil and Gas Developments in Utah and Nevada in 1961

Exploratory drilling in Utah remained at the same level as that of the previous year with a slight increase of total footage. The success ratio of exploratory wells was 17.2% down 7.6% from 1960. Significant exploratory activity included three areas. Completions in the Four Corners part of the Paradox basin expanded the potential of that province, and discoveries in the southern part of the Uinta basin portend a considerable extent of Wasatch and Mesaverde gas accumulations. Of particular significance was the successful completion in the Grassy Trail area north of the San Rafael Swell. This marks the first commercial oil production in this province from Triassic Moenkopi sands. Development drilling was up 14.5%, reflecting the exploitation of gas discoveries in the Uinta basin. The success ratio of 88.1% was up 4.5% from the previous year. Oil production was down 11.9%, largely resulting from conservation measures enacted by the Utah Oil and Gas Commission, but gas production increased 27.0% with the development of the Uinta basin and Lisbon field. Leasing of Federal acreage increased again in 1961, and more than 18 million acres are now under lease. A little over 5% of this is contained in the 57 units in effect. Nevada has one 2,200-acre unit with 1¼ million acres under lease. In Nevada, 13 exploratory wells were drilled in contrast to only 4 tests completed in 1960. These were mostly shallow tests within a restricted area in Churchill County. The outlook for 1962 is for increased activity in exploration for gas in the Uinta basin; continuing development of the Lisbon area, and more widespread drilling for Mississippian objectives elsewhere in the Paradox basin.

Outline of Tectonic History of Mexico: ABSTRACT

The principal morphotectonic provinces of Mexico are: (1) Sierra Madre del Sur composed of middle Paleozoic metamorphics, (2) Sierra Madre Oriental made up of folded Mesozoic carbonates resting on folded Paleozoic sediments overlying Precambrian crystallines, (3) Gulf Coastal Plain and Yucatan Peninsula consisting of Tertiary marine sediments affected locally by salt tectonics and resting on folded Mesozoic sediments and Paleozoic metamorphics, (4) Sierra Madre Occidental consisting of flat-lying Tertiary lavas and pyroclastics which rest on folded Mesozoic sediments and Paleozoic metamorphics, (5) Trans-Mexico Volcanic Belt of late Tertiary and Quaternary age, (6) Sonoran Basin and Range Province comprising folded and faulted Paleozoic and Mesozoic sediments and volcanic , and (7) Baja California Peninsula composed of Cretaceous granitic batholiths and Mesozoic and Tertiary clastics and volcanics. Present structure and resultant physiography developed from the consolidation of three orthogeosynclines into as many structural belts, two of which bordered the southern peninsular extension of the Precambrian hedreocraton of North America and underwent regional metamorphism and granitic emplacement during the middle Paleozoic orogeny at the end of the Paleozoic and block-faulting with accompanying volcanic activity during early Mesozoic time. The third structural belt of Mesozoic-Tertiary age developed from an orthogeosyncline which covered the entire country from south to north and was affected by regional metamorphism and granitic emplacement in its western part toward the end of the Cretaceous and by orogeny mainly in its eastern part during early Tertiary time. This orogeny, which formed the Sierra Madre Oriental, was followed in the western two-thirds of the country by block-faulting and extensive volcanism during the remainder of the Tertiary, whereas east of the present Sierra Madre front deltaic deposits filled the molasse basins grading eastward into finer clastics of the Gulf Coast. During Pleistocene and Recent time a chain of basaltic volcanoes developed along a belt crossing the country from east to west at th latitude of Mexico City. To date, commercial oil production has only been established in the Coastal Plain of the Gulf of Mexico; in the northern and southern districts, production is obtained from Tertiary clastics filling the molasse basins, whereas in the central district it comes from carbonates of the late Jurassic and Cretaceous miogeosyncline. End_of_Article - Last_Page 412------------

San Emidio Nose Field, Kern County, California: ABSTRACT

Twenty-five years ago the first deep wildcat well to explore the large subsurface San Emidio anticline was abandoned, with no promising indications of commercial oil production. Anticipated upper Miocene reservoir rocks continued to elude five more exploratory efforts during the ensuing twenty-three years. Reef Ridge sands were found to be thin or not present, and Stevens sands generally silty and impermeable. First commercial Reef Ridge production was proven in July, 1958, when Richfield Oil Corporation K.C.L. H No. 34-9 was completed flowing 350 b/d clean 30° gravity oil and 46 mcf gas through a 12/64^Prime bean from the interval 11,451-11,558 feet. Development of the H-33 pool commenced with completion of K.C.L. H No. 83-9 at a rate of 440 b/d clean 31° g avity oil and 50 mcf gas through an 8/64^Prime bean from the interval 12,702-12,838 feet. Current daily production from both zones in twenty-two wells is about 7,000 b/d gross. Characterized by a lack of structural complexity, the area has several well defined lithologic units that record contrasting environments of sedimentation. Overlying and sealing the stratigraphically closed Reef Ridge reservoir sand is the impervious, well bedded Reef Ridge shale, youngest Miocene formation present. Gross lithologic characteristics allow subdivision of the Reef Ridge sand interval into an upper member of massive, moderately sorted, contiguous sands and a lower member of poorly bedded, generally less permeable sands. Between Reef Ridge and H-33 sands is 300 feet of impermeable upper Mohnian siltstone. H-33 reservoir sands are fine-grained, moderately to well sorted and divisible into an upper series of thin-bedded lenticular sands and a lower massive unit. End_of_Article - Last_Page 127------------

Reservoir Study of the Roosevelt Pool, Utah

The Roosevelt pool in the Uintah basin of North-eastern Utah produces a high pour-point, high paraffin content crude oil from limestones and sand stringers in the Green River formation at a depth of about 10,000 ft. Due to the low matrix permeability of the rock the productivity of the wells was found to depend upon fracture development. Total production to March 1, 1957, from nine wells was 1,669,000 bbl and current capacity production from six wells is 450 BOPD with 440 BWPD. Production to date has been as a result of fluid expansion coupled with some water encroachment. Introduction and Geology The discovery of oil in the Green River formation at Roosevelt by the completion of the Roosevelt Unit No. 1 in June, 1949, marked the first production in the Uintah basin from reservoirs of Tertiary age. This well was completed for a flowing potential of 1,633 bbl of oil and no water at a depth of 9,350 ft. Following the Roosevelt discovery, a number of other pools were discovered in the area, including Duchesne, Red Wash, Flat Mesa and Walker Hollow. At the top of this page is a map of the Uintah basin, which is a structural, topographic and sedimentary basin in Northeastern Utah covering an area of approximately 8,000 sq miles. On this map A marks the Roosevelt pool; B Duchesne pool; C Red Wash-Walker Hollow pool; D Gusher No. 1; E Bluebell Unit No. 1; F Flat Mesa pool; and G County pool. All commercial oil production at Roosevelt has been obtained from the "D" zone of the Basal Green River. The Green River is a 4,000-ft section of well-bedded oil shales, marlstones, thin dolomites, limestones, and sandstones. The "D" zone is encountered in the lower 1,500 ft of the section with production from this interval being dependent upon a combination of structure, stratigraphy, and fracture development. The Roosevelt pool is located on a broad northwest-southeast trending nose, approximately 7 miles south of the Uintah basin synclinal axis. Fig. 1 presents a structure map of the area and Fig. 2 is cross section of the pool constructed from radioactivity logs. An extensive coring and testing program was followed at many wells in an effort to correlate and identify the pay zones. As shown by the cross section, two main intervals of production totalling approximately 125 ft in gross thickness have been observed, of which the upper has been the more important.

Williston Basin Developments, 1951-1953: ABSTRACT

The phenomenal rate of development in the Williston basin can best be visualized by remembering that at the end of 1950 there was not one producing oil well within the basin parts of North Dakota, South Dakota, Montana, Saskatchewan, or Manitoba. During three years of unprecedented exploratory drilling which followed the first commercial production of oil in the Williston basin (Virden field, T. 10 N., R. 28 WPM., Manitoba, Canada), 55 oil fields, 20 field extensions, and 4 gas fields have been discovered. During this period, production has been established from 16 different formations. One of the most spectacular discoveries during this period came in August, 1953, when End_Page 945------------------------------ flush production at 2,100 feet was developed in the Lodgepole (Mississippian) in the Roselea field, 56 miles north of the North Dakota line in Manitoba. Subsequent wells in the Roselea field have reported initials as high as 2,500 barrels of oil per day. The lack of sufficient well information makes it impractical to calculate the reserves represented by the fields thus far discovered; however, the most conservative estimate places this figure between 500 million and 1 billion barrels of recoverable oil. The year 1953 witnessed the completion of the 300,000 barrels per day Interprovincial Pipe Line from Edmonton, Alberta, to Sarnia, Ontario, and marked the beginning of construction of three new refineries in North Dakota, which on completion will process 33,500 barrels of basin crude daily. 1953 also saw the completion of the 100,000-barrel-per-day common carrier Service Pipe Line from the Beaver Lodge-Tioga area to Mandan, North Dakota, the beginning of construction of a natural-gasoline plant at Tioga, North Dakota, and the completion of Stanolind's products line from Mandan to Fargo, North Dakota. There remains, however, an urgent need for additional marketing facilities before the full economic potential of the basin can be realized. Judged from recent official and unofficial anno ncements, plans to create new facilities are under way and the next five years should show marked progress in this direction. With geophysical activity maintaining its record-breaking pace, and millions of acres of leases approaching one year closer to the expiration date of their primary terms, it is expected that 1954 will witness an unprecedented wildcat and field development program in the Williston basin. Excellent shallow production in Manitoba, the discovery of the first commercial oil in South Dakota, plus continued success in Montana, North Dakota, and Saskatchewan will serve as an incentive to substantiate this 1954 prediction. End_of_Article - Last_Page 946------------

Central Coast Ranges: ABSTRACT

In this arbitrary division are situated the Cuyama Valley, Carrizo Plain, Salinas Valley, San Andreas trough, Halfmoon Bay-Santa Cruz area, and the Livermore-Contra Costa basin. Combined area of these basins is 4,500 square miles with an estimated volume of sediments of 6,500 cubic miles. Seventy-five per cent of the sediments are believed to be marine. Commercial oil production was not discovered until 1948. There are now four substantial producing fields in the Cuyama Valley and two in the Salinas Valley. There were 377 exploratory wells drilled to December 31, 1949. The complex structure and stratigraphy of these basins make them difficult to prospect and many more wildcats will have to be drilled to explore thoroughly the oil and gas possibilities. End_of_Article - Last_Page 2383------------

Santa Maria Region: ABSTRACT

The Santa Maria province is a roughly triangular area in the California coastal belt which is bounded on the west by the Pacific Ocean, on the south by the Santa Ynez Mountains, and on the north and northeast by the Santa Lucia Range. The province consists of several more or less isolated structural basins with similar sedimentary histories and related types of objective zones and traps. Many types of rocks underlie the zones of present and prospective production. The term, basement, as used in this paper, refers to rocks older than Eocene that consist of Jurassic metamorphics and basic intrusives and Cretaceous and Jurassic sediments that have undergone various degrees of alteration. The Santa Maria province has an area of 2,126 square miles, of which 1,824 square miles are underlain by objective sediments. The volume of unaltered sediments is estimated at 1,112 cubic miles and the maximum depth to basement rocks is approximately 16,000 feet. About 400 exploratory wells have been drilled in the province, resulting in the discovery of 14 productive areas with a cumulative production to December 31, 1949, of slightly more than 300 million barrels of oil. Production is largely from Miocene sands, shales, and cherts. Significant amounts of oil have been produced from lower Pliocene sands and in one area from fractured sandstones of Jurassic age. This Jurassic production is considered to have migrated from overlapping Miocene beds. End_Page 2383------------------------------ Prospective sediments range in age from Eocene to Pliocene. They are marine, with the exception of minor amounts of lower Miocene non-marine beds near basement highs and a veneer of upper Pliocene and Pleistocene continental beds in the central portion of the province. Commercial oil production comes from anticlinal closures and stratigraphic and fault traps. It is probable that substantial undiscovered reserves of heavy crude exist in this province, and that lighter oils may be found in parts of the stratigraphic section or in areas not before subjected to intensive search. Stratigraphic and structural studies may well be expected to yield important discoveries. End_of_Article - Last_Page 2384------------

Developments in Rocky Mountain Region in 1948

Two hundred and seventy-seven exploratory wells were drilled in the Rocky Mountain region during 1948. Of these, 73 were successful. This represented a gain over the previous year, 1947, when, of 185 exploratory wells, 49 were successful. Permian and Pennsylvanian objectives provided the most new discoveries. New pools discovered by the Sinclair-Wyoming Oil Company in the Deadwood formation of Cambrian age at Wertz and Lost Soldier, Sweetwater County, Wyoming, and by the Pure Oil Company in the Mesa Verde formation at West Poison Spider, Natrona County, Wyoming, were of great significance as neither of these formations had hitherto been productive in the Rocky Mountain states. Other important discoveries were in the basal Amsden at Big Wall and Melstone in central Montana and in the Hermosa formation at Dove Creek and Boundary Butte in the Four Corners area of Colorado and Utah. A deeper-pool discovery in the Weber formation at Ashley Valley, Uintah County, by the Equity Oil Company provided the source for the first commercial oil production in Utah. Geophysical work increased during 1948, with the center of activity in Wyoming. Production of crude oil showed gains corresponding with the increased rate of exploratory drilling. Development drilling progressed rapidly particularly at Mush Creek, Weston County, Wyoming, where 88 new producers are reported. At Rangely, the development of the Weber Sand pool neared completion at the close of the year.

Developments in Rocky Mountain Region in 1947

There were sixteen new discoveries made in the Rocky Mountain region during 1947. Of these sixteen discoveries, six were based on surface geology, seven on geophysics, and three on a combination of geophysics and geology. The commercial production of oil from the Casper formation (Pennsylvanian) at Herrick Dome in the Laramie Basin, Wyoming, opened another producing zone in this area that bad heretofore been considered doubtful. Production of oil from the Kibbey sand (upper Mississippian) at Ragged Point, Montana, can be classed as a new producing zone in that state. The presence of commercial oil in the Madison limestone (Mississippian) in the Lost Soldier field of Wyoming opened a hitherto unknown reserve in an old established field. Twenty-five successful outpost wells were drilled during the year and five successful deep-pool tests were completed. New reserves to the extent of 160 million barrels of oil were added to the present proved reserves of the Rocky Mountain region. The successful development of shallow sand traps along the northeast rim of the Powder River Basin in Wyoming indicates similar possibilities in other areas of the Rocky Mountain region. Exploration activity was the highest on record, with a total of eighty seismograph parties and forty-six gravity parties operating in the region at one time. The most intense geophysical work and the largest number of crews was concentrated in the basin areas of Wyoming. Also significant was the acceptance by the industry of photogeology as an economic exploration method. More than 110,000 square miles of the region were photogeologized with the discovery of many unmapped structures and areas of potential structural significance.

Rose Hill Oil Field, Lee County, Virginia: ABSTRACT

Commercial production of high-gravity paraffine-base oil from Middle Ordovician limestones beneath the Pine Mountain overthrust block was initiated in 1942 in the Fourmile Window near Ewing, Lee County, Virginia. Drilling activities since May, 1946, have been sufficiently successful to End_Page 2159------------------------------ arouse national interest in the field. In January, 1947, production was extended into the Martin Creek Window, 4 miles northeast of the discovery wells on Fourmile Creek, Some oil has since been obtained from the intervening area, and some of the successful wells have penetrated thin remnants of the overthrust block. Drilling activities, shooting, and acidizing work are summarized. The stratigraphic characteristics of the field and the evolution of the trapping structures are discussed with particular reference to the manner of accumulation and other fundamental problems. End_of_Article - Last_Page 2160------------

The Pacific Coast Petroleum Industry

THE petroleum industry on the Pacific Coast is located principally in California. Although explorations have been made, no commercial production of oil has been developed in Oregon or Washington. The producing fields in California are located in three general areas. The largest of the producing areas is in the San Joaquin Valley which is the southern half of the great central valley of California. Production from this area currently totals 429,000 bbl. daily. The second largest producing area is in Southern California and is usually designated as the Los Angeles Basin. This area extends inland from the coast south of the mountain ranges separating the San Joaquin Valley from the southern part of the state. Production from this area is at present 336,000 bbl. daily. The third, producing area is commonly called the Coastal Area and extends northward from the Los Angeles Basin along the coast and into the Santa Maria Valley. Production ...

Cambrian and Ordovician Rocks in Recent Wells in Southeastern Michigan

All of the wells drilled to pre-Cambrian rocks in the Southern Peninsula of Michigan are located in five counties in the southeastern part of the state bordering the province of Ontario, Canada. The depth to pre-Cambrian in this area ranges from 3,300 feet in Lenawee County to 6,400 feet in Washtenaw County. The thickness of Middle Ordovician rocks penetrated in these wells varies from 660 feet in Lenawee County to 965 feet in St. Clair County and Upper Ordovician rocks from 585 feet in Washtenaw County to 750 feet in Lenawee County. Lower Ordovician rocks have not been found east of Livingston County. A well drilled on the Howell anticline, near the center of Livingston County, drilled 40 feet of St. Peter sandstone and was abandoned without penetrating the entire thickness of the sandstone. Small areas of commercial oil production occurring in the upper part of the dolomitized Trenton limestone of Middle Ordovician age have been found in Lenawee, Monroe, and Wayne counties, and oil is produced from Middle Orodvician rocks in Kent County, southwestern Ontario. Rocks of Upper Cambrian age underlie Middle Ordovician rocks and rest on pre-Cambrian rocks in a large part of southeastern Michigan. The thickness of Cambrian rocks varies from 1,160 feet in Washtenaw County to 140 feet in St. Clair County. This variation in thickness is due to the unconformity at the base of Middle Ordovician rocks which was brought about by uplift and erosion at the close of Lower Ordovician time. Cambrian rocks are missing in parts of Kent, Lambton, and other counties in southwestern Ontario, and in these places Middle Ordovician rocks overlie pre-Cambrian rocks. Showings of gas have been reported from the upper part of the Mount Simon sandstone, of Upper Cambrian age, in some of the wells in southeastern Michigan and showings of oil and gas have been found in Cam rian rocks in some wells in parts of southwestern Ontario where these rocks are present.

Developments in Southeastern States in 1944

Prompted by discoveries of oil fields in Florida and Mississippi late in 1943 and in Alabama and Mississippi in the early months of 1944, the southeastern states have enjoyed their most active period of geophysical and drilling exploration during 1944. Alabama had its first commercial oil production as a result of discovery of the Gilbertown field by H. L. Hunt's A. R. Jackson No. 1, Sec. 2, T. 10 N., R. 4 W., Choctaw County, on February 16, 1944. Nine producers and 5 dry holes were drilled in the field during the year. Accumulative production for Gilbertown was 56,064 barrels through December, 1944. In addition to the Gilbertown development, there were 21 wildcat wells drilled in Alabama: 4 in the Paleozoic province of northwest Alabama and 17 in the southern and southwestern part of the state. During 1943, 9 wildcats were drilled and abandoned. Six wells were abandoned in Florida during 1944, one less than were drilled during the preceding year. In the Sunniland field, Collier County, the Humble Oil and Refining Company's Gulf Coast Realty Company No. 1 pumped 11,832 barrels of 19° A.P.I. gravity oil in 1944. This is Florida's only producing well. No production was established by 6 wells completed in Georgia in 1944. The year's development in Mississippi was high-lighted by (1) discovery of 5 new fields in the southern part of the state; (2) proof of an appreciable oil-rim around the Cranfield structure in Adams County; (3) discovery of Eutaw production in the Eucutta field, Wayne County; and (4) minor extension of producing area in the Pickens field, Madison and Yazoo counties. Four shallow piercement salt domes were discovered in 1944, and they, as well as several previously discovered domes, have been explored for sulphur. Only the Richton dome, Perry County, yielded non-commercial sulphur showings. The Sun Oil Company's Hammett No. 1-A, Bruinsburg dome, Claiborne County, Mississippi, was completed, November 22, 1944, as a small gas well to mark first production on an interior piercement salt dome in Mississippi. Showings of gas in the Freeport Sulphur Company tests had encouraged later exploration. Of the 1944 new discoveries, the Heidelberg field, Jasper County, has seen most rapid development due to diverse lease ownership and moderate producing depths. Production from the 57 wells completed in 1944 is from Eutaw and upper Tuscaloosa, on a graben fault system overlying a deep-seated salt dome. The 4 other discoveries have had too little development for reasonable accuracy in predicting their significance. Three widely spaced wells have been completed in the Gwinville field, Jefferson Davis County. Only the discovery well is on production in the Mallalieu field, Lincoln County, in the Baxterville field, Lamar County, and in the Bruinsburg field, Claiborne County. In 1944 there were 72 wildcats drilled (5 productive, 67 dry), 51 sulphur tests, and 129 field wells (113 productive, 16 dry). The figures for 1943 were: 59 wildcats (4 productive, 55 dry), 12 sulphur tests, and 36 field wells (28 productive, 8 dry). The increasing success of wildcatting in Mississippi has resulted from more satisfactory interpretation of detailed geophysical surveys.

Basal Vicksburg Sand of Texas Gulf Coast: ABSTRACT

The discovery of commercially important oil sands at the base of the Vicksburg formation, on the flanks of some Texas Gulf Coast dome structures during the past few years, recalls the necessity for constant re-examination of the older producing areas by methods which make full use of the newest proved geological tools. This paper employs the now common electrical well log, in conjunction with the best paleontological opinions, to identify and to map the areal extent and thickness of the basal Vicksburg sand in the Texas Gulf Coast, and to predict, with some foundation, its future possibilities for commercial oil production on the older known structures. Electrical well log cross sections through the region, two of them down the dip and one along the sedimentary strike, are given in support of the sand thickness map. End_of_Article - Last_Page 931------------

Commercial Production of Oil from Coal

ON July 14, the House of Lords debated a Motion by Lord Mottistone that plant for obtaining oil from coal should be set up in Durham and South Wales in the interests both of national defence and increase of employment. Lord McGowan said that the experience of Imperial Chemical Industries, Ltd., has established the technical possibility of such processes but at capital and operating costs so high that the process, even with the assistance of existing protection, is not attractive to private capital. Success would have to depend not on private initiative, but on Government policy. The production of heavy oil for marine purposes from coal is at present uneconomical. The effect on employment ought not to be exaggerated. A plant capable of producing 150,000 tons of petrol annually provides work for 6,000 persons of whom 2,500 would be miners. Low-temperature carbonization and hydrogenation are complementary processes, and increased use of smokeless household fuels would promote both national security and national welfare. Hydrogenation processes, he emphasized, are a question of high national policy and beyond the purview of an ordinary limited liability company. Reference was made to the Fischer process and other methods of developing the use of coal. Lord Hutchinson, in reply, said the Government is awaiting the report of Lord Fal-mouth's Committee before deciding its policy for the production of oil from coal. Meanwhile, it is encouraging the establishment of plant for carbonizing coal at low temperatures, and another will be in production in South Wales next year.

Claiborne Possibilities of the Laredo Area: ABSTRACT

The discovery of commercial oil and gas production in the Claiborne section of southwest Texas and northern Mexico during the past year or two has brought this area into prominence. The various oil and gas producing horizons of this area are discussed and two cross sections prepared to show the relation of one field to another and correlate them with adjacent areas in northern Mexico. The possibility of deep production on several relatively unknown structures in the area is pointed out together with notes on the older fields producing from the Claiborne section. End_of_Article - Last_Page 140------------

Buckeye Field, Matagorda County, Texas

The Buckeye field is on a very deep-seated domal uplift; it covers about 800 acres, according to the surface indications and a magnetometer survey. The first well drilled came in as a producer, August 31, 1932. Seven wells have been completed, and of these, two were commercial producers. The wells on a west-east cross section indicate that the uplift may cover less than 800 acres. A study of the subsurface reveals that the Upper Catahoula is undoubtedly of Miocene age. The oil horizon occurs in the upper part of the Lower Catahoula (Frio), at the depth of approximately 7,800 feet. This was the deepest commercial oil production in the Texas Gulf Coast at the time of its discovery. The field produced 362,397 barrels before the wells stopped flowing, and is still producing s all quantities of oil on the pump. The field has been subdivided into 20-acre units.