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Kenneth J. Bird

Publications and source records attributed to Kenneth J. Bird.

At least 55 records · Page 3Linked to original sources

Petroleum source potential of the Lower Cretaceous mudstone succession of the NPRA and Colville Delta area, North Slope Alaska, based on sonic and resistivity logs

Resource assessment of the North Slope of Alaska by the U. S. Geological Survey includes evaluation of the petroleum source potential of Mesozoic and Cenozoic rocks using the delta log R technique (Passey and others, 1990). Porosity and resistivity logs are used in combination with thermal maturity data to produce a continuous profile of total organic carbon content in weight % (TOC). From the pattern and amount of TOC in the profile produced, the depositional setting and thus the petroleum source-rock potential (kerogen type) of the organic matter can be inferred and compared to interpretations from other data such as Rock-Eval pyrolysis. TOC profiles determined by this technique for the contiguous interval of pebble shale unit, Hue Shale (including the Gamma Ray Zone or GRZ), and lower part of the Torok Formation indicate important potential for petroleum generation in the Tunalik 1, Inigok 1, N. Inigok 1, Kuyanak 1, Texaco Colville Delta 1, Nechelik 1, and Bergschrund 1 wells of the western North Slope region. TOC profiles suggest that this interval contains both type II and III kerogens – consistent with proposed depositional models -- and is predominantly greater than 2 wt. % TOC (cut-off used for effective source potential). Average TOC for the total effective section of the pebble shale unit + Hue Shale ranges from 2.6 to 4.1 wt % TOC (values predominantly 2-8% TOC) over 192-352 ft. Source potential for the lower Torok Formation, which also has interbedded sandstone and lean mudstone, is good to negligible in these 7 wells.

Alaska

North Alaska petroleum system analysis: The regional map compilation

The U.S. Geological Survey initiated an effort to model north Alaskan petroleum systems. The geographic and geologic basis for modeling systems is provided by a set of regional digital maps that allow evaluation of the widest possible extent of each system. Accordingly, we laid out a rectangular map grid 1300 km (800 miles) east-west and 600 km (375 miles) north-south. The resulting map area extends from the Yukon Territory of Canada on the east to the Russian-U.S. Chukchi Sea on the west and from the Brooks Range on the south to the Canada basin-Chukchi borderland on the north. Within this map region, we combined disparate types of publicly available data to produce structure contour maps. Data types range from seismic-based mapping as in the National Petroleum Reserve to well penetrations in areas of little or no seismic data where extrapolation was required. With these types of data, we produced structure contour maps on three horizons: top of pre-Mississippian (basement), top of Triassic (Ellesmerian sequence), and top of Neocomian (Beaufortian sequence). These horizons, when combined with present-day topography and bathymetry, provide the bounding structural/stratigraphic surfaces of the north Alaskan petroleum province that mark major defining moments of the region's geologic history and allow regional portrayal of preserved sediment accumulations.

Alaska, Yukon

Revised Cretaceous and Tertiary stratigraphic nomenclature in the Colville Basin, Northern Alaska

A revised stratigraphic nomenclature is proposed for Cretaceous and Tertiary geologic units of the central and western North Slope of Alaska. This revised nomenclature is a simplified and broadly applicable scheme suitable for a suite of digital geologic quadrangle maps being prepared jointly by the U.S. Geological Survey and the Alaska Department of Natural Resources, Division of Geological and Geophysical Surveys and Division of Oil and Gas. This revised nomenclature scheme is a simplification of a complex stratigraphic terminology that developed piecemeal during five decades of geologic investigations of the North Slope. It is based on helicopter-supported geologic field investigations incorporating information from high-resolution aerial photography, satellite imagery, paleontology, reflection seismic records, and sequence stratigraphic concepts. This revised nomenclature proposes the abandonment of the Colville Group; demotion of the Nanushuk Group to formation status; abandonment of six formations (Kukpowruk, Tuktu, Grandstand, Corwin, Chandler, and Ninuluk); revision of four formations (Sagavanirktok, Prince Creek, Schrader Bluff, and Seabee); elevation of the Tuluvak Tongue of the Prince Creek Formation to formation status; revision of two members (Franklin Bluffs Member and Sagwon Member of the Sagavanirktok Formation); abandonment of eight members or tongues (Kogosukruk, Rogers Creek, Barrow Trail, Sentinel Hill, Ayiyak, Shale Wall, Niakogon, and Killik); and definition of one new member (White Hills Member of the Sagavanirktok Formation).

Professional Paper

U.S. Geological Survey 2002 petroleum resource assessment of the National Petroleum Reserve in Alaska (NPRA): play maps and technically recoverable resource estimates

This report provides a summary of the estimated volume of technically recoverable undiscovered oil and nonassociated gas resources for each of the 24 plays evaluated in the U.S. Geological Survey 2002 petroleum resource assessment of the NPRA (Bird and Houseknecht, 2002). It also provides a set of illustrations showing the stratigraphic and geographic location of each play. Additional details of this assessment will follow in later publications.

Alaska

A digital atlas of hydrocarbon accumulations within and adjacent to the National Petroleum Reserve-Alaska (NPRA)

The United States Geological Survey (USGS) has initiated a project to reassess the hydrocarbon potential of the NPRA. Although exploration for hydrocarbons in the NPRA was initiated in 1944, it has taken fifty years for the first commercial discovery to be made. That discovery, the Alpine field (projected recoverable reserves of 430 million barrels), was made in 1994 along the eastern boundary of the NPRA. This field produces from a formation heretofore considered to be mostly a source rock. The Alpine discovery made such a reassessment necessary. As part of this assessment, we have compiled stratigraphic, structural, petrophysical, and seismic data related to nineteen accumulations within and nearby the NPRA. The goal is to provide basic documentation and a set of analog accumulations for the new assessment. The first two displays of this atlas consist of a location map and a stratigraphic column showing the stratigraphic settings for the primary reservoir and source rocks for these accumulations. The third display is a table listing each accumulation and providing the hydrocarbon fluid type, reservoir, operator, status, and discovery well and date for each. Compilation of basic information for each individual accumulation follows these displays. A typical compilation includes a structurecontour map on or near the reservoir horizon, a log display of the discovery well with reservoir characteristics along with figures for recoverable volumes, and one or two seismic lines across or near the accumulation.

Alaska

Lithofacies and stratigraphy of the Lisburne and Etivluk groups in the Lisburne 1 well and adjacent outcrops

The Lisburne 1 well in the thrust belt of the central Brooks Range penetrated 17,000 ft of imbricated, chiefly Ellesmerian sequence strata in the Endicott Mountains allochthon. Five thrust repeats of the Lisburne Group (Carboniferous) and overlying Etivluk Group (Permian-Jurassic) were drilled. Lithofacies analyses of >350 thin sections of cores and cuttings, and biostratigraphy based on foraminifers and conodonts, allow detailed correlation with coeval units in adjacent outcrops and provide data on the depositional setting and reservoir and source rock potential of these strata. The late Early- Late Mississippian (Osagean-Chesterian) Lisburne Group consists mainly of skeletal wackestone to grainstone, locally completely dolomitized. An interval of abundant glauconite and detrital quartz in the lower Lisburne may mark a sequence-bounding unconformity. Dolostone in the upper part of the unit has maximum porosities of 10-13% and common residual hydrocarbons. The uppermost Lisburne is thinly interbedded mudstone, chert, and shale that are locally dolomitic, phosphatic, spiculitic, and organic-rich; conodonts from this interval in outcrop represent an outer shelf to slope biofacies. The Etivluk Group here encompasses the Siksikpuk and Otuk Formations. The Siksikpuk is mainly varicolored shale and radiolarian chert, with a basal interval of glauconitic, pyritic sandstone. Phosphatic and organic-rich shale, radiolarian chert, and pelecypod coquinas make up the Otuk. Outcrop and subsurface data indicate that the Lisburne Group in this area accumulated near the seaward margin of a shallow-water carbonate platform that drowned during the Late Mississippian; outer shelf or deeper conditions predominated throughout deposition of the upper Lisburne and the Etivluk Group.

AAPG Bulletin

Alaska: A twenty-first-century petroleum province

Alaska, the least explored of all United States regions, is estimated to contain approximately 40% of total U.S. undiscovered, technically recoverable oil and natural-gas resources, based on the most recent U.S. Department of the Interior (U.S. Geological Survey and Minerals Management Service) estimates. Northern Alaska, including the North Slope and adjacent Beaufort and Chukchi continental shelves, holds the lion's share of the total Alaskan endowment of more than 30 billion barrels (4.8 billion m 3 ) of oil and natural-gas liquids plus nearly 200 trillion cubic feet (5.7 trillion m 3 ) of natural gas. This geologically complex region includes prospective strata within passive-margin, rift, and foreland-basin sequences. Multiple source-rock zones have charged several regionally extensive petroleum systems. Extensional and compressional structures provide ample structural objectives. In addition, recent emphasis on stratigraphic traps has demonstrated significant resource potential in shelf and turbidite systems in Jurassic to Tertiary strata. Despite robust potential, northern Alaska remains a risky exploration frontier - a nexus of geologic complexity, harsh economic conditions, and volatile policy issues. Its role as a major petroleum province in this century will depend on continued technological innovations, not only in exploration and drilling operations, but also in development of huge, currently unmarketable natural-gas resources. Ultimately, policy decisions will determine whether exploration of arctic Alaska will proceed.

Alaska

Stratigraphy and lithofacies of Lisburne Group carbonate rocks (Carboniferous - Permian) in the National Petroleum Reserve - Alaska

Carbonate rocks of the Lisburne Group (Carboniferous-Permian) occur widely throughout northern Alaska. In the NPRA, seismic mapping and well penetrations show that the Lisburne occurs throughout the subsurface except in northernmost NPRA where it is missing by depositional onlap. Lisburne strata encountered in 11 exploratory wells in the northern part of the NPRA are essentially undeformed, consist of limestone and lesser dolostone, sandstone, siltstone, and shale, encompass a wide array of chiefly shallow-water facies, and range in age from Early Mississippian to Permian. Basins and platforms that formed during Mississippian (and possibly Devonian) time greatly affected depositional patterns of the Lisburne. Total thickness of the Lisburne in northern NPRA wells varies from almost 4000 ft in the Ikpikpuk-Umiat Basin to 300 ft on the north edge of the Fish Creek Platform. Lisburne strata of Mississippian age are found in northeastern NPRA, comprise three subunits (lower limestone, middle dolostone, and upper limestone) and are oldest (Osagean) in the Ikpikpuk-Umiat Basin. All wells that penetrated the Lisburne in northern NPRA encountered rocks of Pennsylvanian age; these intervals are mainly limestone and characterized by decameter-scale shallowing-upward sequences. Lisburne sections of prob-able Early-middle Permian age range from thin (≤60 ft) intervals of dolostone and limestone in the Fish Creek Platform area to thick (500-1000 ft) successions of interbedded limestone and siliciclastic sediment in the Ikpikpuk-Umiat Basin and northwestern NPRA. Abundant non-carbonate detritus, primarily quartz and chert with locally notable plagioclase feldspar and metamorphic lithic clasts, occurs throughout the Lisburne Group in northern NPRA. Per-mian strata and a persistent non-carbonate detrital component are also seen in the Lisburne in subsurface beneath the Chukchi Sea (Hanna Trough) to the northwest, but are not found in Lisburne successions elsewhere in Alaska.

Alaska

Application of well data in oil and gas assessment - Arctic National Wildlife Refuge

A current assessment of oil and gas resources in the Arctic National Wildlife Refuge 1002 area by the U.S. Geological Survey relies upon seismic data, geological mapping of exposures south and west of the assessment area and exploratory wells. Well data assembled for the 41 wells include: well logs, core descriptions and measurements, formation tops, biostratigraphic boundaries, drill-stem tests, casing points, fission-track age dates, vitrinite reflectance, and organic-carbon content. These data are used in the synthesis of all available data and presentation on a well-by-well basis, and extraction of volumetric parameters that are used to assess undiscovered accumulations.

Conference Paper

Economics and the national oil and gas assessment: The case of onshore northern Alaska

The National Oil and Gas Assessment of undiscovered recoverable conventional oil and gas resources assigned nearly 36% of the undiscovered U.S. onshore oil resources and 28% of the commercially developable undiscovered oil resources to onshore northern Alaska. Economic screening models were applied to the geologic play assessment to estimate the commercially developable resources. This paper presents the geologic and economic assessment methodology and results; it also focuses on the robustness of estimates of the commercially developable onshore resources to changes in economic assumptions. With the economic assumptions used in the national assessment, about 60% or 6.49 billion bbl of oil of the recoverable undiscovered resources of 10.76 billion bbl of oil assessed in fields larger than 1 million bbl of oil are estimated to be commercially developable. Changes in facilities costs induced the most significant cost-related response in the commercially developable resource estimates. Price increases or cost reductions that reduce the minimum commercially developable field size to 250 million bbl from the base case size of 380 million bbl added 1 billion bbl of oil to the commercially developable resources. If, through facilities sharing or satellite-field development, the minimum commercial field size is reduced to just below 100 million bbl, estimated developable oil woul increase to 9.17 billion bbl of oil or more than 85% of the assessed recoverable oil in onshore plays.

Alaska

Lisburne Group (Mississippian and Pennsylvanian), potential major hydrocarbon objective of Arctic Slope, Alaska

The Lisburne Group, a thick carbonate-rock unit of Mississippian and Pennsylvanian age, is one of the most widespread potential reservoir-rock units in northern Alaska. A comprehensive review of the Lisburne in the subsurface of the eastern Arctic Slope indicates attractive reservoir characteristics in a favorable source and migration setting where numerous trapping mechanisms appear to be available. Evaluation of this group as a potential exploration objective is particularly timely because of impending offshore sales in the Beaufort Sea and current exploration programs under way in the Prudhoe Bay area and the Naval Petroleum Reserve. Dolomite and sandstone have been identified as reservoir rocks. Oolitic grainstone is a common rock type, but observations indicate little reservoir potential owing to complete void filling by calcite cement. The most important reservoir rock as judged by thickness, areal extent, and predictability is microsucrosic (10 to 30μ) dolomite of intertidal to supratidal origin. It is present throughout the Lisburne and is most abundant near the middle of the sequence. Northward it decreases in thickness from 1,000 ft (300 m) to less than 100 ft (30 m). Porosity of the dolomite as determined in selected wells averages between 10 and 15% and attains a maximum of slightly more than 25%. Net thickness of reservoir rocks (i.e., rocks with greater than 5% porosity) ranges in these wells from 140 to 390 ft (40 to 120 m). Oil shows are common, and drill-stem tests have yielded as much as 1,600 bbl/day of oil and 22 MMcf/day of gas in the Lisburne pool of the Prudhoe Bay field and as much as 2,057 bbl/day of salt water outside the field area. The occurrence of dolomite over such a large area makes its presence in the offshore Beaufort Sea and adjacent Naval Petroleum Reserve 4 fairly certain. The presence of sandstone as thick as 140 ft (40 m) in the middle and upper part of the Lisburne in two coastal wells suggests that larger areas of sandstone may be found on the north in offshore areas. Shows of oil and gas and a saltwater flow of 1,470 bbl/day have been recorded from this sandstone facies. Shales of Permian and Cretaceous ages unconformably overlie the Lisburne, providing adequate sealing beds above potential reservoirs. Impermeable limestone (completely cemented grainstone) and thin beds of shale may serve as seals within the Lisburne, but the possibility of fractures in these units may negate their sealing capability. The most favorable source rock for Lisburne hydrocarbons appears to be Cretaceous shale that unconformably overlies the Lisburne east of Prudhoe Bay. This shale is reported to be a rich source rock and is the most likely source for the entire Prudhoe Bay field. A source within the Lisburne or within the underlying Kayak Shale is postulated for oil shows in the southernmost Lisburne wells. This postulated source may be in a more basinal facies of the Lisburne and may be similar to dark shale in the upper Lisburne in thrust slices to dark shale in the upper Lisburne in thrust slices in the Brooks Range. Coal in the underlying Endicott Group is a possible source for dry gas. At present, much of this coal probably is in a gas-generating regime downdip from the Prudhoe Bay field. Stratigraphic traps involving the Lisburne Group may have resulted from widespread Permian and Cretaceous unconformities. Structural traps related to normal faulting may be present along the trend of the Barrow arch, and faulted anticlines are numerous in the foothills of the Brooks Range. Combination traps are possible along the trend of the Barrow arch.

Alaska