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Maps

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Thermal maturity map of Devonian shale in the Illinois, Michigan, and Appalachian basins of North America

Much of the oil and gas in the Illinois, Michigan, and Appalachian basins of eastern North America is thought to be derived from Devonian shale that is within these basins (for example, Milici and others, 2003; Swezey, 2002, 2008, 2009; Swezey and others, 2005, 2007). As the Devonian strata were buried by younger sediments, the Devonian shale was subjected to great temperature and pressure, and in

Surficial geologic map of the Ivanpah 30' x 60' quadrangle, San Bernardino County, California, and Clark County, Nevada

This map was prepared as part of a suite of surficial geologic maps covering the northern Mojave Desert to investigate neotectonic features and map soils of relevance for ecological properties. The map covers an area of the eastern Mojave Desert that includes the Cinder Cones, Cima Dome, Ivanpah Valley, and Lanfair Valley and includes major mountain chains of the Providence, New York, and Ivanpah

Geologic cross section C-C' through the Appalachian basin from Erie County, north-central Ohio, to the Valley and Ridge province, Bedford County, south-central Pennsylvania

Geologic cross section C-C' is the third 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 C-C' provides a regional view of the structural and stratigraphic framework of the Appalachian basin from north-central Ohio to the Valley and Ridge provi

Aeromagnetic and aeromagnetic-based geologic maps of the Coastal Belt, Franciscan Complex, northern California

The Coastal belt of the Franciscan Complex represents a Late Cretaceous to Miocene accretionary prism and overlying slope deposits. Its equivalents may extend from the offshore outer borderland of southern California to north of the Mendocino Triple Junction under the Eel River Basin and in the offshore of Cascadia. The Coastal belt is exposed on land in northern California, yet its structure and

Thermal Maturity Patterns (CAI and %Ro) in Upper Ordovician and Devonian Rocks of the Appalachian Basin: A Major Revision of USGS Map I-917-E Using New Subsurface Collections

The conodont color alteration index (CAI) introduced by Epstein and others (1977) and Harris and others (1978) is an important criterion for estimating the thermal maturity of Ordovician to Mississippian rocks in the Appalachian basin. Consequently, the CAI isograd maps of Harris and others (1978) are commonly used by geologists to characterize the thermal and burial history of the Appalachian bas

Geology and Mineral Resources of the East Mojave National Scenic Area, San Bernardino County, California

From our evaluations that largely used model-based criteria, we conclude that much of the East Mojave National Scenic Area (EMNSA) contains significant indications of epigenetic mineralization of various types. Economically significant concentrations of many metals may possibly remain to be discovered in many parts of the EMNSA (see also Wetzel and others, 1992). We have discussed specific types o

Geologic map and map database of western Sonoma, northernmost Marin, and southernmost Mendocino counties, California

This digital map database, compiled from previously published and unpublished data, and new mapping by the authors, represents the general distribution of bedrock and surficial deposits in the mapped area. Together with the accompanying text file (wsomf.ps, wsomf.pdf, wsomf.txt), it provides current information on the geologic structure and stratigraphy of the area covered. The database delineates

Geologic map and map database of northeastern San Francisco Bay region, California: Most of Solano County and parts of Napa, Marin, Contra Costa, San Joaquin, Sacramento, Yolo, and Sonoma Counties

This digital map database, compiled from previously published and unpublished data, and new mapping by the authors, represents the general distribution of bedrock and surficial deposits in the mapped area. Together with the accompanying text file (nesfmf.ps, nesfmf.pdf, nesfmf.txt), it provides current information on the geologic structure and stratigraphy of the area covered. The database delin

Geologic map and map database of the Spreckels 7.5-minute Quadrangle, Monterey County, California

Introduction The Spreckels quadrangle lies at the north end of the Sierra de Salinas and extends from the Salinas Valley on the northeast across Los Laurelles Ridge south to Carmel Valley, an intermontane valley that separates the Santa Lucia Range from the Sierra de Salinas (fig. 1). The Toro Regional Park occupies the east-central part of the quadrangle, whereas the former Fort Ord Military R

Geologic maps and structure sections of the southwestern Santa Clara Valley and southern Santa Cruz Mountains, Santa Clara and Santa Cruz Counties, California

This digital map database, compiled from previously published and unpublished data, and new mapping by the authors, represents the general distribution of bedrock and surficial deposits in the mapped area. Together with the accompanying text file (scvmf.ps, scvmf.pdf, scvmf.txt), it provides current information on the geologic structure and stratigraphy of the area covered. The database delineat

Geologic map of the Lamoille Quadrangle, Elko County, Nevada

A 1:24,000-scale, full-color geologic map of the Lamoille 7.5-minute quadrangle in Elko County, Nevada, with one cross section and descriptions of 17 geologic units. 

Geologic map and map database of the Palo Alto 30' x 60' quadrangle, California

This digital map database, compiled from previously published and unpublished data, and new mapping by the authors, represents the general distribution of bedrock and surficial deposits in the mapped area. Together with the accompanying text file (pamf.ps, pamf.pdf, pamf.txt), it provides current information on the geologic structure and stratigraphy of the area covered. The database delineates