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Robert T. Ryder

Publications and source records attributed to Robert T. Ryder.

At least 19 recordsLinked to original sources
USGS2024

Cross section N–N' through the Valley and Ridge province of the southern Appalachian basin, from Greene County, west-central Alabama, to Bibb County, central Alabama

Introduction Geologic cross section N–N′ is the sixth in a series of geologic cross sections constructed by the U.S. Geological Survey to document and improve understanding of the geologic framework and petroleum systems of the Appalachian basin. Cross section N–N′ provides a regional view of the structural and stratigraphic framework of the Appalachian basin in the Valley and Ridge province in western and central Alabama; it spans approximately 69 miles (mi) (111 kilometers [km]). This geologic cross section is a companion to geologic cross sections E–E′ , D–D′ , C–C′ , I–I′ , and A–A′ that are located approximately 350 to 550 mi (563 to 885 km) to the northeast. Cross section N–N' complements earlier geologic cross sections through the Alabama part of the Appalachian basin. Although some of the other cross sections show more structural and stratigraphic detail, they are of more limited extent geographically and stratigraphically. Cross section N–N′ contains information that is useful for evaluating energy resources in the Appalachian basin. Although the Appalachian basin petroleum systems are not shown on the cross section, many of their key elements (such as source rocks, reservoir rocks, seals, and traps) can be inferred from lithologic units, unconformities, and geologic structures shown on the cross section. Other aspects of petroleum systems (such as the timing of petroleum generation and petroleum migration pathways) may be evaluated by burial history, thermal history, and fluid flow models based on what is shown on the cross section. In addition, cross section N–N′ may be used as a reconnaissance tool to identify plausible geologic structures and strata for the subsurface storage of liquid waste or for the sequestration of carbon dioxide.

Alabama↗
USGS2021

Organic geochemistry and petrology of Devonian shale in eastern Ohio: Implications for petroleum systems assessment

Recent production of light sweet oil has prompted reevaluation of Devonian petroleum systems in the central Appalachian Basin. Upper Devonian Ohio Shale (lower Huron Member) and Middle Devonian Marcellus Shale organic-rich source rocks from eastern Ohio and nearby areas were examined using organic petrography and geochemical analysis of solvent extracts to test ideas related to organic matter sources, oil–source rock correlation, thermal maturity, and distances of petroleum migration. The data from these analyses indicate organic matter in the Ohio and Marcellus Shales primarily was derived from marine algae and its degradation products, including bacterial biomass. Absence of odd-over-even n - alkane distributions (n - C 13 to n - C 21 range) in gas chromatograms and low gammacerane index values in Devonian source rocks are similar to those of Devonian-reservoired oils in eastern Ohio, suggesting an oil–source rock correlation. Lower Paleozoic oils from eastern Ohio, in contrast, are characterized by the presence of odd-over-even n - alkane distributions (n - C 13 to n - C 21 range) and higher gammacerane values, which discriminate them from Devonian shale-derived oils. Thermal maturity estimates from equilibrium(?) biomarker isomerization ratios suggest that some of the Devonian source rock samples are at middle to peak oil window conditions (i.e., approximate vitrinite reflectance values of 0.8%–0.9%). This observation requires local to short-distance (<50 mi) lateral migration for emplacement of Devonian-sourced oils into Devonian reservoirs of eastern Ohio and may impact exploration and assessment of petroleum resources in the Upper Devonian Berea Sandstone.

Ohio↗
USGS2019

Geologic cross section A–A′ through the Appalachian basin from the southern margin of the Ontario Lowlands province, Genesee County, western New York, to the Valley and Ridge province, Lycoming County, north-central Pennsylvania

Introduction Geologic cross section A–A′ is the fifth in a series of cross sections constructed by the U.S. Geological Survey (USGS) to document and improve understand­ing of the geologic framework and petroleum systems of the Appalachian basin. Cross section A–A′ provides a regional view of the structural and stratigraphic frame­work of the Appalachian basin from the southern mar­gin of the Ontario Lowlands province in western New York, across the Allegheny Plateau province of central New York and north-central Pennsylvania, to the Valley and Ridge province in north-central Pennsylvania, a dis­tance of approximately 176 miles. This cross section is a companion to cross sections E–E′, D–D′, C–C′ , and I–I′ that are located approximately 100 to 500 miles to the southwest. Cross section A–A′ complements earlier geologic or strati­graphic cross sections through the central New York and north-central Pennsylvania part of the Appalachian basin. Although some of these other cross sections show more structural and stratigraphic detail, they are of more limited extent geographically and stratigraphically. Cross section A–A′ contains much information that is useful for evaluating energy resources in the Appalachian basin. Although the Appalachian basin petroleum systems are not shown on the cross section, many of their key elements (such as source rocks, reservoir rocks, seals, and traps) can be inferred from lithologic units, unconformities, and geologic structures shown on the cross section. Important oil- and gas-bearing formations like the Oriskany Sandstone, Medina Group sandstones, Tuscarora Sandstone, and the Marcellus and Utica Shales are present on cross-section A–A′ .

New York, Pennsylvania↗
USGS2015

Geologic Cross Section I–I′ Through the Appalachian Basin from the Eastern Margin of the Illinois Basin, Jefferson County, Kentucky, to the Valley and Ridge Province, Scott County, Virginia

Geologic cross section I‒I&rsquo; is the fourth in a series of cross sections constructed by the U.S. Geological Survey to document and improve understanding of the geologic framework and petroleum systems of the Appalachian basin. Cross section I‒I&rsquo; provides a regional view of the structural and stratigraphic framework of the Appalachian basin from the eastern margin of the Illinois basin in central Kentucky, across the Cincinnati arch (Lexington dome), to the Valley and Ridge province in southwestern Virginia, a distance of approximately 280 miles. This cross section is a companion to cross sections E‒E&rsquo; , D‒D&rsquo; , and C‒C&rsquo; that are located about 200 to 300 miles to the northeast. Cross section I‒I&rsquo; either updates or complements earlier geologic cross sections through the central Kentucky and southwestern Virginia part of the Appalachian basin. Although other published cross sections through parts of the basin show more structural and stratigraphic detail, these other cross sections are of more limited extent geographically and (or) stratigraphically. Cross section I‒I &rsquo; contains much information that is useful for evaluating energy resources in the Appalachian basin. Many of the key elements of the Appalachian basin petroleum systems (such as source rocks, reservoir rocks, seals, and traps) can be inferred from lithologic units, unconformities, and geologic structures shown on the cross section. Other aspects of petroleum systems (such as the timing of petroleum generation and petroleum migration pathways) may be evaluated by burial history, thermal history, and fluid flow models on the basis of what is shown on the cross section. Cross section I‒I&rsquo; also provides a stratigraphic and structural framework for the Pennsylvanian coal-bearing section. In addition, geologists and engineers could use cross section I‒I&rsquo; as a reconnaissance tool to identify plausible geologic structures and strata for the subsurface storage of liquid waste or for the sequestration of carbon dioxide.

Kentucky, Pensylvania↗
USGS2014

Executive summary

Fossil fuels from the Appalachian basin region have been major contributors to the Nation&rsquo;s energy needs over much of the last three centuries. Early records indicate that Appalachian coal was first mined in the middle 1700s (Virginia and Pennsylvania) and was used sparingly to fuel colonial settlements and, later, a fledgling industrial-based economy along the eastern seaboard of the United States (de Witt and Milici, 1989). In 2011, central Appalachian basin coal production accounted for approximately 77 percent of all U.S. metallurgical (or coking) coal and 29 percent of total U.S. production (U.S. Energy Information Administration, 2013). Following initial discoveries and commercial use in western New York (1821) and Ohio and West Virginia (mid-1830s), the Appalachian petroleum (oil and gas) industry began in earnest in 1859 with the discovery of oil at the Drake well in northwestern Pennsylvania. Between 1860 and 1989, the Appalachian basin produced more than 2.5 billion barrels of oil (BBO) and more than 30 trillion cubic feet of gas (TCFG) from more than 500,000 wells (de Witt and Milici, 1989). Although both oil and gas continue to be produced in the Appalachian basin, most new wells in the region are drilled in shale reservoirs to produce natural gas. Appalachian coal and petroleum resources are still available in sufficient quantities to contribute significantly to the Nation&rsquo;s energy needs. For example, the U.S. Energy Information Administration (2010) estimated that there are 6,484 million short tons of recoverable coal reserves in the Appalachian basin. Similarly, about 14.7 billion barrels of oil equivalent (BBOE) (1.2 BBO+81 TCFG [or 13.5 BBOE]) of recoverable Appalachian basin oil and gas remain available of an estimated ultimate endowment of approximately 25.5 billion BBOE (cumulative production + reserves + estimated recoverable undiscovered resources) (this volume, chap. C.1). U.S. Geological Survey (USGS) Professional Paper 1708 is a modern, indepth collection of reports, cross sections, and maps that describe the geology of the Appalachian basin and its fossil fuel resources. Several of the chapters have been published in outside journals or as other USGS publications. Although this volume is not a comprehensive regional treatment of all notable geologic and fossil fuel localities in the Appalachian basin, the selected study areas and topics presented in the chapters cover large segments of the basin and a wide range of stratigraphic intervals. As the title implies, this volume addresses topics that refer to the locations of coal and petroleum accumulations, the stratigraphic and structural framework, and the geochemical characteristics of the coal beds and petroleum in the basin, as well as the results and documentation of recent USGS assessments of coal, oil, and gas resources in the basin. Many of the maps and accompanying data supporting the reports in this volume are available as downloadable geographic information system (GIS) data files (such as selected coal beds, selected oil and gas fields, locations of oil and gas wells, coal production, coal chemistry, total petroleum system (TPS) boundaries, and bedrock geology). Log ASCII Standard (LAS) files for geophysical (gamma ray) wireline well logs also are included. This publication supplements and updates older USGS regional studies of Appalachian basin coal and petroleum resources such as those by Arndt and others (1968) and the numerous contributors to USGS Miscellaneous Map Series I&minus;917 (for example, Harris and others, 1978), respectively. USGS Professional Paper 1708 is intended primarily for geoscientists in academia, industry, and government who are interested in Appalachian basin geology and its coal and petroleum resources. Other users, however, may find the wide variety of topics, papers, and digital images of value for landuse and policy planning issues. Among the anticipated benefits of the report are improvements in (1) resource assessment estimates and methodology, (2) exploration strategies, (3) basin models, and (4) energy use policies.

Appalachian Basin↗
USGS2014

Appalachian basin oil and natural gas: stratigraphic framework, total petroleum systems, and estimated ultimate recovery

The most recent U.S. Geological Survey (USGS) assessment of undiscovered oil and gas resources of the Appalachian basin was completed in 2002 (Milici and others, 2003). This assessment was based on the total petroleum system (TPS), a concept introduced by Magoon and Dow (1994) and developed during subsequent studies such as those by the U.S. Geological Survey World Energy Assessment Team (2000) and by Biteau and others (2003a,b). Each TPS is based on specific geologic elements that include source rocks, traps and seals, reservoir rocks, and the generation and migration of hydrocarbons. This chapter identifies the TPSs defined in the 2002 Appalachian basin oil and gas assessment and places them in the context of the stratigraphic framework associated with regional geologic cross sections D&ndash;D &prime; (Ryder and others, 2009, which was re-released in this volume, chap. E.4.1) and E&ndash;E &prime; (Ryder and others, 2008, which was re-released in this volume, chap. E.4.2). Furthermore, the chapter presents a recent estimate of the ultimate recoverable oil and natural gas in the basin.

Appalachian basin↗
USGS2014

Geographic information system (GIS)-based maps of Appalachian basin oil and gas fields

One of the more recent maps of Appalachian basin oil and gas fields (and the adjoining Black Warrior basin) is the U.S. Geological Survey (USGS) compilation by Mast and others (1998) (see Trippi and others, this volume, chap. I.1). This map is part of a larger oil and gas field map for the conterminous United States that was derived by Mast and others (1998) from the Well History Control System (WHCS) database of Petroleum Information, Inc. (now IHS Energy Group). Rather than constructing the map from the approximately 500,000 proprietary wells in the Appalachian and Black Warrior part of the WHCS database, Mast and others (1998) subdivided the region into a grid of 1-mi 2 (square mile) cells and allocated an appropriate type of hydrocarbon production (oil production, gas production, oil and gas production, or explored but no production) to each cell. Each 1-mi 2 cell contains from 0 to 5 or more exploratory and (or) development wells. For example, if the wells in the 1-mi 2 cell consisted of three oil wells, one gas well, and one dry well, then the cell would be characterized on the map as an area of oil and gas production. The map by Mast and others (1998) accurately shows the distribution and types of hydrocarbon accumulation in the Appalachian and Black Warrior basins, but it does not show the names of individual fields. To determine the locality and name of individual oil and gas fields, one must refer to State oil and gas maps (for example, Harper and others, 1982), which are generally published at scales of 1:250,000 or 1:500,000 (see References Cited), and (or) published journal articles. Other recent USGS Appalachian basin oil and gas field maps show the distribution of oil and gas production with a cell size as small as 0.25 mi 2 , such as the maps converted by Trippi and others (this volume, chap. I.1) from proprietary well-location maps used in the USGS 2002 assessment of oil and gas resources of the Appalachian basin (Milici and others, 2003). Another set of Appalachian basin oil and gas cell maps (based on a cell size of 0.25 mi 2 ) was created for the USGS 1995 National Assessment of United States Oil and Gas Resources (Gautier and others, 1995; Beeman and others, 1996). Between 1991 and 1994, R.T. Ryder (with R.E. Mattick, J.B. Roen, and J.R. San Filipo, USGS, Reston, Va.) compiled oil and gas fields on stable-base mylar greenline base maps (scale 1:500,000) for selected plays in the Appalachian basin. These map compilations included field names and field numbers where assigned by State agencies. The purpose of the maps was to provide supporting data for the USGS 1995 National Assessment of United States Oil and Gas Resources (Gautier and others, 1995). In particular, the greenline oil and gas field maps were linked, where possible, with production data from State records and (or) published literature in order to determine ultimate sizes for conventional fields and estimated ultimate recovery (EUR) values for wells in continuous accumulations (for definitions of the conventional and continuous terminology, see USGS National Oil and Gas Assessment Team, 1995; Schmoker, 1997; Schenk and Pollastro, 2002). This approach was used in the 1995 national oil and gas assessment because ultimate field size and EUR data were unavailable in the Appalachian region from Petroleum Information, Inc., and other commercial sources. In 2006 and 2007, the greenline Appalachian basin field maps were digitized under the supervision of Scott Kinney and converted to geographic information system (GIS) files for chapter I.1 (this volume). By converting these oil and gas field maps to a digital format and maintaining the field names where noted, they are now available for a variety of oil and gas and possibly carbon-dioxide sequestration projects. Having historical names assigned to known digitized conventional fields provides a convenient classification scheme into which cumulative production and ultimate field-size databases can be organized. Moreover, as exploratory and development drilling expands across the basin, many previously named fields that were originally treated as conventional fields have evolved into large, commonly unnamed continuous-type accumulations. These new digital maps will facilitate a comparison between EUR values from recently drilled, unnamed parts of continuous accumulations and EUR values from named fields discovered early during the exploration cycle of continuous accumulations.

Appalachian basin↗
USGS2014

Index map of cross sections through parts of the Appalachian basin (Kentucky, New York, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia)

Ten cross sections and three seismic profiles of regional extent through the subsurface of the Appalachian basin are presented in chapter E of this volume (fig. 1). These cross sections and seismic profiles are subdivided into four groups: (1) five restored cross sections through Cambrian and Ordovician rocks, (2) three restored cross sections through Lower and Upper (part) Silurian rocks, (3) two geologic (structural) cross sections through the entire preserved section of Paleozoic rocks, and (4) three seismic profiles through the entire preserved section of Paleozoic rocks. The stratigraphic units in the restored cross sections are constructed with respect to a horizontal lithologic datum, whereas the stratigraphic units in the geologic (structural) cross sections are constructed with respect to sea level. The control points for the cross sections are exploratory wells drilled for oil and gas, and many of these wells reached igneous and metamorphic basement rocks of Mesoproterozoic age. Each cross section is illustrated in detail and discussed at length in its respective chapter. The cross sections and seismic profiles included in this volume were previously published between 1991 and 2009 as U.S. Geological Survey publications; some of these publications were subsequently revised. The earliest cross sections (chapters E.2.1 to E.2.4) refer to an unpublished cross section ( A&ndash;A&prime; ); that cross section was never published later and is not the A&ndash;A&prime; included here as chapter E.3.3. The cross sections are included in this volume in their original form to provide support for assessments and research studies in the Appalachian basin. There are two additional USGS publications that are not included in this volume but may be useful for research studies: Ryder and others (1996) and Ryder and others (2012). The appendixes in chapters E.4.1 and E.4.2 include (1) Log ASCII Standard (LAS) files, which encode gamma-ray, neutron, density, and other logs in text files that can be used by most well-logging software programs; and (2) graphic well-log traces. In the appendix to chapter E.4.1, the well-log traces are accompanied by lithologic descriptions with formation tops.

Appalachian basin↗
USGS2014

Stratigraphic framework of Cambrian and Ordovician rocks in the central Appalachian basin from Medina County, Ohio, through southwestern and south-central Pennsylvania to Hampshire County, West Virginia

This chapter is a re-release of U.S. Geological Survey Bulletin 1839-K, of the same title, by Ryder and others (1992; online version 2.0 revised and digitized by Robert D. Crangle, Jr., 2003). It consists of one file of the report text as it appeared in USGS Bulletin 1839-K and a second file containing the cross section, figures 1 and 2, and tables 1 and 2 on one oversized sheet; the second file was digitized in 2003 as version 2.0 and also includes the gamma-ray well log traces.

Appalachian basin↗
USGS2014

Geologic cross section D-D' through the Appalachian basin from the Findlay arch, Sandusky County, Ohio, to the Valley and Ridge province, Hardy County, West Virginia

This chapter is a re-release of U.S. Geological Survey Scientific Investigations Map 3067, of the same title, by Ryder and others (2009). For this chapter, two appendixes have been added that do not appear with the original version. Appendix A provides Log ASCII Standard (LAS) files for each drill hole along cross-section D-D' ; they are text files which encode gamma-ray, neutron, density, and other logs that can be used by most well-logging software. Appendix B provides graphic well-log traces and lithologic descriptions with formation tops from each drill hole.

Appalachian basin↗
USGS2014

Geologic cross section E-E' through the Appalachian basin from the Findlay arch, Wood County, Ohio, to the Valley and Ridge province, Pendleton County, West Virginia

This chapter is a re-release of U.S. Geological Survey Scientific Investigations Map 2985, of the same title, by Ryder and others (2008). For this chapter, two appendixes have been added that do not appear with the original version. Appendix A provides Log ASCII Standard (LAS) files for each drill hole along cross-section E&ndash;E' ; they are text files which encode gamma-ray, neutron, density, and other logs that can be used by most well-logging software. Appendix B provides graphic well-log traces from each drill hole.

Appalachian basin↗