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Steven M. Condon

Publications and source records attributed to Steven M. Condon.

15 recordsLinked to original sources
USGS2003

Potential for deep basin-centered gas accumulation in Travis Peak (Hosston) Formation, Gulf Coast Basin, U.S.A.

The potential of Lower Cretaceous sandstones of the Travis Peak Formation in the northern Gulf Coast Basin to harbor a basin-centered gas accumulation was evaluated by examining (1) the depositional and diagenetic history and reservoir properties of Travis Peak sandstones, (2) the presence and quality of source rocks for generating gas, (3) the burial and thermal history of source rocks and time of gas generation and migration relative to tectonic development of Travis Peak traps, (4) gas and water recoveries from drill-stem and formation tests, (5) the distribution of abnormal pressures based on shut-in-pressure data, and (6) the presence or absence of gas-water contacts associated with gas accumulations in Travis Peak sandstones. The Travis Peak Formation (and correlative Hosston Formation) is a basinward-thickening wedge of terrigenous clastic sedimentary rocks that underlies the northern Gulf Coast Basin from eastern Texas across northern Louisiana to southern Mississippi. Clastic influx was focused in two main fluvial-deltaic depocenters—one located in northeastern Texas and the other in southeastern Mississippi and northeastern Louisiana. Across the main hydrocarbon-productive trend in eastern Texas and northern Louisiana, the Travis Peak Formation is about 2,000 ft thick. Most Travis Peak hydrocarbon production in eastern Texas comes from drilling depths between 6,000 and 10,000 ft. Significant decrease in porosity and permeability occurs through that depth interval. Above 8,000-ft drilling depth in eastern Texas, Travis Peak sandstone matrix permeabilities often are significantly higher than the 0.1-millidarcy (mD) cutoff that characterizes tight-gas reservoirs. Below 8,000 ft, matrix permeability of Travis Peak sandstones is low because of pervasive quartz cementation, but abundant natural fractures impart significant fracture permeability. Although pressure data within the middle and lower Travis Peak Formation are limited in eastern Texas, overpressured reservoirs caused by thermal generation of gas, typical of basin-centered gas accumulations, are not common in the Travis Peak Formation. Significant overpressure was found in only one Travis Peak sandstone reservoir in 1 of 24 oil and gas fields examined across eastern Texas and northern Louisiana. The presence of gas-water contacts is perhaps the most definitive criterion indicating that a gas accumulation is conventional rather than a “sweet spot” within a basin-centered gas accumulation. Hydrocarbon-water contacts within Travis Peak sandstone reservoirs were documented in 17 fields and probably occur in considerably more fields across the productive Travis Peak trend in eastern Texas and northern Louisiana. All known hydrocarbon-water contacts in Travis Peak reservoirs in eastern Texas, however, occur within sandstones in the upper 500 ft of the formation. Although no gas-water contacts have been reported within the lower three-fourths of the Travis Peak Formation in northeastern Texas, gas production from that interval is limited. The best available data suggest that most middle and lower Travis Peak sandstones are water bearing in northeastern Texas. Insufficient hydrocarbon charge relative to permeability of Travis Peak reservoirs might be responsible for lack of overpressure and basin-centered gas within the Travis Peak Formation. Shales interbedded with Travis Peak sandstones in eastern Texas are primarily oxidized flood-plain deposits with insufficient organic-carbon content to be significant sources of oil and gas. The most likely source rocks for hydrocarbons in Travis Peak reservoirs are two stratigraphically lower units, the Jurassic-age Bossier Shale of the Cotton Valley Group, and laminated, lime mudstones of the Jurassic Smackover Formation. Hydrocarbon charge, therefore, might be sufficient for development of conventional gas accumulations, but it is insufficient for development of basin-centered gas as a result of the absence of proximal source rocks and a lack of effective migration pathways from stratigraphically or geographically distant source rocks.

Louisiana, Mississippi, Texas↗
USGS2002

Is there a basin-centered gas accumulation in Cotton Valley group sandstones, Gulf Coast basin, U.S.A.?

The U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Energy, is reevaluating the resource potential of selected domestic basin-centered gas accumulations. Basin-centered gas accumulations are characterized by presence of gas in extensive low-permeability (tight) reservoirs in which conventional seals and trapping mechanisms are absent, abnormally high or low reservoir pressures exist, and gas-water contacts are absent. In 1995, the USGS assessed one basin-centered gas play and two conventional plays within the trend of Jurassic and Cretaceous Cotton Valley Group fluvial-deltaic and barrier island/strand plain sandstones across the onshore northern Gulf of Mexico Basin. Detailed evaluation of geologic and production data provides new insights into these Cotton Valley plays. Two Cotton Valley sandstone trends are identified based on reservoir properties and gas-production characteristics. Transgressive blanket sandstones across northern Louisiana have relatively high porosity and permeability and do not require fracture stimulation to produce gas at commercial rates. South of this trend, and extending westward into eastern Texas, massive sandstones of the Cotton Valley trend exhibit low porosity and permeability and require fracture stimulation. The high permeability of Cotton Valley blanket sandstones is not conducive to the presence of basin-centered gas, but low permeability massive sandstones provide the type of reservoir in which basin-centered gas accumulations commonly occur. Data on source rocks, including burial and thermal history, are consistent with the interpretation of potential basin centered gas within Cotton Valley sandstones. However, pressure gradients throughout most of the blanket- and massive sandstone trends are normal or nearly normal, which is not characteristic of basin-centered gas accumulations. The presence of gas-water contacts in at least seven fields across the blanket-sandstone trend together with relatively high permeabilities and high gas-production rates without fracture stimulation indicate that fields in this trend are conventional. Within the tight massive-sandstone trend, permeability is sufficiently low that gas-water transition zones are vertically extensive and gas-water contacts either have not been encountered or are poorly defined. With increasing depth through these transition zones, gas saturation decreases and water saturation increases until eventually gas saturations become sufficiently low that, in terms of ultimate cumulative production, wells are noncommercial. Such progressive increase in water saturation with depth suggests that poorly defined gas-water contacts probably are present below the depth at which wells become noncommercial. The interpreted presence of gas-water contacts within the tight, Cotton Valley massive-sandstone trend suggests that gas accumulations in this trend, too, are conventional, and that a basin-centered gas accumulation does not exist within Cotton Valley sandstones in the northern Gulf Basin.

Louisiana, Texas↗
USGS2000

Stratigraphic framework of Lower and Upper Cretaceous rocks in central and eastern Montana

This study shows the lithology, thickness, distribution, and correlation of Lower and Upper Cretaceous rocks in central and eastern Montana. The described stratigraphic units range from the Aptian Kootenai Formation (oldest) to the Maastrichtian Hell Creek Formation (youngest). An included text report describes the units, and most formations or members are also represented by isopach maps. Structure contour maps of three horizons are also included. Correlations across the study area are shown on a series of cross sections. All text and illustrations are included as Adobe PDF files.

Montana↗
USGS1997

Geology of the Pennsylvanian and Permian Cutler Group and Permian Kaibab Limestone in the Paradox Basin, southeastern Utah and southwestern Colorado

The Cutler Formation is composed of thick, arkosic, alluvial sandstones shed southwestward from the Uncompahgre highlands into the Paradox Basin. Salt tectonism played an important role in deposition of the Cutler in some areas. In the northeast part of the basin, more than 8,000 ft, and as much as 15,000 ft, of arkose was trapped between rising salt anticlines - this arkose is thin to absent over the crests of some anticlines. In the western and southern parts of the basin, the Cutler is recognized as a Group consisting of, in ascending order: the lower Cutler beds, Cedar Mesa Sandstone, Organ Rock Formation, White Rim Sandstone, and De Chelly Sandstone. The aggregate thickness of these formations is less than 2,000 ft. The formations of the Cutler Group were deposited in a complex system of alluvial, eolian, and marine environments characterized by abrupt vertical and lateral lithologic changes. The basal Cutler is Pennsylvanian in age, but the bulk of the Group was deposited during the Permian. The Cutler is conformably underlain by the Pennsylvanian Hermosa Group across most of the basin. It is overlain unconformably by the Permian Kaibab Limestone in the western part of the Paradox Basin. The Cutler or Kaibab are overlain unconformably by the Triassic Moenkopi or Chinle Formations.

Arizona, Colorado, New Mexico, Utah↗
USGS1997

Geology and structure of the Pine River, Florida River, Carbon Junction, and Basin Creek gas seeps, La Plata County, Colorado

Introduction: This study was commissioned by a consortium consisting of the Bureau of Land Management, Durango Office; the Colorado Oil and Gas Conservation Commission; La Plata County; and all of the major gas-producing companies operating in La Plata County, Colorado. The gas-seep study project consisted of four parts; 1) detailed surface mapping of Fruitland Formation coal outcrops in the above listed seep areas, 2) detailed measurement of joint and fracture patterns in the seep areas, 3) detailed coal-bed correlation of Fruitland coals in the subsurface adjacent to the seep areas, and 4) studies of deep-seated seismic patterns in those seep areas where seismic data was available. This report is divided into three chapters labeled 1, 2, and 3. Chapter 1 contains the results of the subsurface coal-bed correla-tion study, chapter 2 contains the results of the surface geologic mapping and joint measurement study, and chapter 3, contains the results of the deep-seismic study. A preliminary draft of this report was submitted to the La Plata County Group in September 1996. All of the members of the La Plata Group were given an opportunity to critically review the draft report and their comments were the basis for revising the first draft to create this final version of a geologic report on the major La Plata County gas seeps located north of the Southern Ute Indian Reservation.

Open-File Report↗
USGS1996

Burial and thermal history of the Paradox Basin, Utah and Colorado, and petroleum potential of the Middle Pennsylvanian Paradox Formation

The Ismay-Desert Creek interval and Cane Creek cycle of the Alkali Gulch interval of the Middle Pennsylvanian Paradox Formation in the Paradox Basin of Utah and Colorado contain excellent organic-rich source rocks having total organic carbon contents ranging from 0.5 to 11.0 percent. The source rocks in both intervals contain types I, II, and III organic matter and are potential source rocks for both oil and gas. Organic matter in the Ismay-Desert Creek interval and Cane Creek cycle of the Alkali Gulch interval (hereinafter referred to in this report as the "Cane Creek cycle") probably is more terrestrial in origin in the eastern part of the basin and is interpreted to have contributed to some of the gas produced there. Thermal maturity increases from southwest to northeast for both the Ismay-Desert Creek interval and Cane Creek cycle, following structural and burial trends throughout the basin. In the northernmost part of the basin, the combination of a relatively thick Tertiary sedimentary sequence and high basinal heat flow has produced very high thermal maturities. Although general thermal maturity trends are similar for both the Ismay-Desert Creek interval and Cane Creek cycle, actual maturity levels are higher for the Cane Creek due to the additional thickness (as much as several thousand feet) of Middle Pennsylvanian section. Throughout most of the basin, the Ismay-Desert Creek interval is mature and in the petroleum-generation window (0.10 to 0.50 production index (PI)), and both oil and gas are produced; in the south-central to southwestern part of the basin, however, the interval is marginally mature (<0.10 PI) for petroleum generation, and mainly oil is produced. In contrast, the more mature Cane Creek cycle contains no marginally immature areas—it is mature (>0.10 PI) in the central part of the basin and is overmature (past the petroleum-generation window (>0.50 PI)) throughout most of the eastern part of the basin. The Cane Creek cycle generally produces oil and associated gas throughout the western and central parts of the basin and thermogenic gas in the eastern part of the basin. Burial and thermal-history models were constructed for six different areas of the Paradox Basin. In the Monument upwarp area, the least mature part of the basin, the Ismay-Desert Creek interval and Cane Creek cycle have thermal maturities of 0.10 and 0.20 PI and were buried to 13,400 ft and 14,300 ft, respectively. A constant heat flow through time of 40 mWm -2 (milliwatts per square meter) is postulated for this area. Significant petroleum generation began at 45 Ma for the Ismay-Desert Creek interval and at 69 Ma for the Cane Creek cycle. In the area around the confluence of the Green and Colorado Rivers, the Ismay-Desert Creek interval and Cane Creek cycle have thermal maturities of 0.20 and 0.25 PI and were buried to 13,000 ft and 14,200 ft, respectively. A constant heat flow through time of 42 mWm -2 is postulated for this area. Significant petroleum generation began at 60 Ma for the Ismay-Desert Creek interval and at 75 Ma for the Cane Creek cycle. In the area around the town of Green River, Utah, the Ismay-Desert Creek interval and Cane Creek cycle have thermal maturities of 0.60 and greater and were buried to 14,000 ft and 15,400 ft, respectively. A constant heat flow through time of 53 mWm -2 is proposed for this area. Significant petroleum generation began at 82 Ma for the Ismay-Desert Creek interval and at 85 Ma for the Cane Creek cycle. Around Moab, Utah, in the deeper, eastern part of the basin, the Ismay-Desert Creek interval and Cane Creek cycle have thermal maturities of 0.30 and around 0.35 PI and were buried to 18,250 ft and 22,000 ft, respectively. A constant heat flow through time of 40 mWm -2 is postulated for this area. Significant petroleum generation began at 79 Ma for the Ismay-Desert Creek interval and at 90 Ma for the Cane Creek cycle. At Lisbon Valley, also in the structurally deeper part of the basin, the Ismayy–Desert Creek interval and Cane Creek cycle have thermal maturities of 0.30 and greater than 0.60 PI and were buried to 15,750 ft and 21,500 ft, respectively. A constant heat flow through time of 44 mWm –2 is postulated for this area. Significant petroleum generation began at 79 Ma for the Ismay–Desert Creek interval and at 100 Ma for the Cane Creek cycle. The area around Hermosa, Colo., in the southeastern part of the basin, has experienced a shallower burial history than the other areas in the basin, yet it has one of the highest thermal maturities. Here, the Ismay–Desert Creek interval and Cane Creek cycle have vitrinite reflectance values of 1.58 and 1.63 percent and were buried to 13,700 ft and 15,500 ft, respectively. Due to Tertiary igneous activity in this part of the basin, a variable heat flow is proposed: from 600 to 30 Ma, 45 mWm –2 ; from 30 to 25 Ma, 63 mWm –2 ; and from 25 Ma to present, 50 mWm –2 . Significant petroleum generation began at 72 Ma for the Ismay–Desert Creek interval and at 76 Ma for the Cane Creek cycle.

Colorado, Utah↗
USGS1992

Geologic framework of pre-Cretaceous rocks in the Southern Ute Indian Reservation and adjacent areas, southwestern Colorado and northwestern New Mexico

This report is a discussion and summary of Jurassic and older rocks in the Southern Ute Indian Reservation and adjacent areas, southwestern Colorado and northwestern New Mexico, and is based on analysis of geophysical logs and observations of outcrops. The Reservation, which is located in the northern San Juan Basin, has been the site of deposition of sediments for much of the Phanerozoic. Geologic times represented on the Reservation are the Precambrian, Cambrian, Devonian, Mississippian, Pennsylvanian, Permian, Triassic, Jurassic, Cretaceous, Tertiary, and Quaternary. Rocks of Ordovician and Silurian age have not been reported in this region. Thicknesses of pre-Cretaceous sedimentary rocks range from about 750 feet (229 meters) on the Archuleta arch, east of the Reservation, to more than 8,300 feet (2,530 meters) just northwest of the Reservation. About 5,500 feet (1,676 meters) of pre-Cretaceous sedimentary rocks occur in the central part of the Reservation, near Ignacio. At Ignacio the top of the Jurassic lies at a depth of 7,600 feet (2,316 meters) below the surface, which is composed of Tertiary rocks. As much as 2,500 feet (762 meters) of Tertiary rocks occur in the area. More than 10,000 feet (3,048 meters) of Cretaceous and younger rocks, and 15,600 feet (4,755 meters) of all Phanerozoic sedimentary rocks occur in the vicinity of the Reservation. In the early Paleozoic the area that includes the Southern Ute Reservation was on the stable western shelf of the craton. During this time sediments that compose the following shallow-marine clastic and carbonate rocks were deposited: the Upper Cambrian Ignacio Quartzite (0-150 feet; 0-46 meters), Upper Devonian Elbert Formation (50-200 feet; 15-61 meters), Upper Devonian Ouray Limestone (10-75 feet; 3-23 meters), and Mississippian Leadville Limestone (0-250 feet; 0-76 meters). Mixed carbonate and clastic deposition, which was punctuated by a unique episode of deposition of evaporite sediments, continued through the Pennsylvanian after a significant episode of erosion at the end of the Mississippian. Pennsylvanian rocks on the Reservation are the Molas Formation (20-100 feet; 6-30 meters) and Hermosa Group (400-2,800 feet; 122-853 meters), which consists of the Pinkerton Trail Formation (40-120 feet; 12-36 meters), Paradox Formation and equivalent rocks (200-1,800 feet; 61-549 meters), and Honaker Trail Formation (200-1,300 feet; 61-396 meters). A unit that is transitional between the Pennsylvanian and Permian is the Rico Formation, which is about 200 feet (61 meters) thick across most of the Reservation area. The close of the Paleozoic Era was marked by a great influx of arkosic clastic sediments from uplifted highlands to the north of the Reservation area during the Permian. Near the paleomountain front the Cutler Formation (presently as thick as 8,000 feet; 2,438 meters) formed as a result of deposition of arkosic sediments; however, the original thickness of the Cutler is unknown due to an unconformity at its top. In the area of the Reservation the Cutler has group status and has been divided into several formations: the Halgaito Formation (350-800 feet; 107-244 meters), Cedar Mesa Sandstone and equivalent rocks (150-350 feet; 46-107 meters), Organ Rock Formation (500-900 feet; 152-274 meters), and De Chelly Sandstone (0-100 feet; 0-30 meters). The sediments of these formations were deposited in a variety of environments, including eolian, mud-flat, and fluvial systems. Following an episode of erosion in the Early and Middle(?) Triassic, deposition in the area of the Southern Ute Reservation continued during the Mesozoic. Sediments of the Upper Triassic Dolores and correlative Chinle Formations were deposited in fluvial, lacustrine, and minor eolian environments. On the Reservation the Dolores is 500-1,200 feet (152-366 meters) thick. Lower Jurassic eolian and fluvial deposits may have been present in much of the Reservation area but have been removed

Professional Paper↗