SEARCH · Geology Reports
Results for “Geologic Quadrangle Map”
Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Bedrock geologic map of the Grafton quadrangle, Worcester County, Massachusetts
The bedrock geology of the 7.5-minute Grafton, Massachusetts, quadrangle consists of deformed Neoproterozoic to early Paleozoic crystalline metamorphic and intrusive igneous rocks. Neoproterozoic intrusive, metasedimentary, and metavolcanic rocks crop out in the Avalon zone, and Cambrian to Silurian intrusive, metasedimentary, and metavolcanic rocks crop out in the Nashoba zone. Rocks of the Avalon and Nashoba zones, or terranes, are separated by the Bloody Bluff fault. The bedrock geology was mapped to study the tectonic history of the area and to provide a framework for ongoing hydrogeologic characterization of the fractured bedrock of Massachusetts. This report presents mapping by G.J. Walsh, geochronology by J.N. Aleinikoff, geochemistry by M.J. Dorais, and consists of a map, text pamphlet, and GIS database. The map and text pamphlet are available in paper format or as downloadable files (see frame at right). The GIS database is available for download. The database includes contacts of bedrock geologic units, faults, outcrops, structural geologic information, and photographs.
Geologic Map of the Carlton Quadrangle, Yamhill County, Oregon
The Carlton, Oregon, 7.5-minute quadrangle is located in northwestern Oregon, about 35 miles (57 km) southwest of Portland. It encompasses the towns of Yamhill and Carlton in the northwestern Willamette Valley and extends into the eastern flank of the Oregon Coast Range. The Carlton quadrangle is one of several dozen quadrangles being mapped by the U.S. Geological Survey (USGS) and the Oregon Department of Geology and Mineral Industries (DOGAMI) to provide a framework for earthquake- hazard assessments in the greater Portland, Oregon, metropolitan area. The focus of USGS mapping is on the structural setting of the northern Willamette Valley and its relation to the Coast Range uplift. Mapping was done in collaboration with soil scientists from the National Resource Conservation Service, and the distribution of geologic units is refined over earlier regional mapping (Schlicker and Deacon, 1967). Geologic mapping was done on 7.5-minute topographic base maps and digitized in ArcGIS to produce ArcGIS geodatabases and PDFs of the map and text. The geologic contacts are based on numerous observations and samples collected in 2002 and 2003, National Resource Conservation Service soils maps, and interpretations of 7.5-minute topography. The map was completed before new, high-resolution laser terrain mapping was flown for parts of the northern Willamette Valley in 2008.
Geologic map of the Rheita Quadrangle of the Moon
Photographs returned by unmanned Lunar Orbiters have contributed greatly to the current lunar geologic mapping program. This is particu larly true for quadrangles near the limbs, such as Rh eita in the southeast earthside quadrant. The new data and revised in terpretations amend the geologic framework established by earlier workers (Shoemaker (1962) and Shoemaker and Hackman (1962) applied basic stratigraphic principles to set up a lunar time scale; McCauly (1967) summarized changes made in he next five years of study; Wilhelms (1970) compiled all the telescopic refinements and additions to the original framework) . Detailed studies of crater morphologies from Lunar Orbiter photographs ( Pohn and Offield , 1970) permit the placement of most craters within the time- stratigraphic systems ( Offield and Pohn , 1970 : Offield , 1971). Other advances in understanding lunar processes included establishing the sequence of formation and features of large, multiringed basins ( McCauly , 1968; Stuart-Alexander and Howard, 1970) and criteria for distinguishing between impacts and possible volcanic craters (McCauly,1968).
Preliminary Bedrock Geologic Map of the Old Lyme Quadrangle, New London and Middlesex Counties, Connecticut
This report presents a preliminary map of the bedrock geology of the Old Lyme quadrangle, New London and Middlesex Counties, Connecticut. The map depicts contacts of bedrock geologic units, faults, outcrops, and structural geologic information. The map was published as part of a study of fractured bedrock aquifers and regional tectonics.
Geologic map of the Hebgen Lake quadrangle, Beaverhead, Madison, and Gallatin counties, Montana, Park and Teton counties, Wyoming, and Clark and Fremont counties, Idaho
The geology of the Hebgen Lake Quadrangle was mapped as part of an Ongoing research effort by the USGS to understand the geologic framework of the area in and around Yellowstone National Park. Prior to 1965 the regional geology was known only from reconnaissance surveys. Two important components of this effort are an evaluation of (1) the seismic risk hazard and (2) the mineral resource potential.
Geologic map of the Monrovia Quadrangle, Liberia
As part of a program undertaken cooperatively by the Liberian Geological Survey and the U. S. Geological Survey, under the sponsorship of the Government of Liberia and the Agency for International Development, U. S. Department of State, Liberia was mapped by geologic and geophysical methods during the period 1965 to 1972.- The resulting geologic and geophysical maps are published in ten folios, each covering one quadrangle (see index map). The Monrovia quadrangle was systematically mapped by the author from June 1971 to July 1972. Field data provided by private companies and other members of the LGS-USGS project were used in map compilation, and are hereby acknowledged. Interpretation of gravity data (Behrendt and Wotorson, 1974, c), and total-intensity aeromagnetic and total count gamma radiation surveys (Behrendt and Wotorson, 1974, a, and b) were also used in the compilation, as were other unpublished geophysical data furnished by Behrendt and Wotorson (near-surface, regional magnetic component, and geologic correlations based on aeromagnetic and radiometric characteristics).
Bedrock geologic map of the Woodstock quadrangle, Grafton County, New Hampshire
The bedrock geology of the Woodstock 7.5-minute quadrangle consists of highly deformed metasedimentary rocks of the Central Maine trough, including the Silurian Rangeley and Perry Mountain Formations and the Devonian Littleton Formation. The central, northern, and eastern parts of the quadrangle are underlain by the oldest rocks in the area, the Rangeley Formation. In the southwest and south-central part of the quadrangle, metaturbidites of the Perry Mountain Formation and subsequent Littleton Formation overly the Rangeley Formation in a deformed F 1 synform, herein informally called the Bagley Brook basin. The metasedimentary rocks were intruded by widespread syn- to post-tectonic granitoids of the Devonian New Hampshire Plutonic Suite and minor post-metamorphic Jurassic-Cretaceous mafic dikes of the White Mountain Plutonic-Volcanic Suite. The metasedimentary rocks were affected by at least two episodes of deformation in the Devonian Acadian orogeny. The dominant regional foliation is second-generation (S 2 /D 2 ) and formed during the development of sillimanite-muscovite mineral assemblages. Large bodies of the Early Devonian Kinsman Granodiorite intruded the metasedimentary rocks semi-concordantly during D 2 deformation. Dikes of the Late Devonian Concord Granite cut the Kinsman Granodiorite and the metasedimentary rocks and were emplaced either syn- or post-D 2 . The map pattern in the Rangeley Formation is dominated by northeast to northwest trending, moderately to steeply north-dipping F 2 and F 3 folds. Map-scale F 1 folds are defined by the Bagley Brook basin. Previous division of Rangeley Formation stratigraphy in this region into “upper” and “lower” parts was not corroborated by 1:24,000-scale mapping of lithodemic units, and rocks previously mapped as part of the Smalls Falls and Madrid Formations are here reassigned to the Rangeley Formation. Some rocks previously mapped as the lower part of the Littleton Formation are now assigned to the Perry Mountain Formation. The Littleton Formation on this map is approximately equivalent to rocks previously mapped as the upper part of the same formation. Steeply dipping fractures in the quadrangle show a preferred northeast orientation, consistent with subsurface fracture orientations in the well fields near Mirror Lake. Jurassic-Cretaceous mafic dikes and normal faults show preferred northeast orientations, similar to the fractures, suggesting that the extensional stress field that controlled dike orientation during the Mesozoic also produced the dominant brittle fabrics in the area.
Geologic map of the Gbanka Quadrangle, Liberia
As part of a program undertaken cooperatively by the Liberian Geological Survey (LGS) and the U. S. Geological Survey (USGS), under the sponsorship of the Government of Liberia and the Agency for International Development, U. S. Department of State, Liberia was mapped by geologic and geophysical methods during the period 1965 to 1972. The resulting geologic and geophysical maps are published in ten folios, each covering one quadrangle (see index map).
Preliminary geologic map of the Dengate quadrangle, Morton County, North Dakota
The Dengate quadrangle is an area of approximately 51 square miles in western Morton County, southwestern North Dakota. The quadrangle is about 40 miles west of Bismarck, the State capitol (fig. 1) and about 3.5 miles east of Glen Ullin (population 1,087). Interstate Highway 94,U.S. Highway 10, and the Northern Pacific Railroad cross the northern part of the area in an east-west direction. The Dengate quadrangle is one of a group of 14 adjoining 71/2-minute quadrangles (fig. 1) that are being mapped by the U.S. Geological Survey to furnish a basis for classification of lands withdrawn by the Federal Government pending classification for coal, and to contribute to the geologic map atlas of the United States. Most of the fieldwork for the Dengate quadrangle was done during the late summers and early autumns of 1965 and 1966. During the summer of 1966, the U.S. Geological Survey conducted a drilling program in the Dengate and nearby quadrangles (Smith, 1970) to gather information on the existence, thickness, and depth of lignite beds in withdrawn Federal lands. Two of the holes drilled are in the Dengate quadrangle.
Bedrock geologic map of the Uxbridge quadrangle, Worcester County, Massachusetts, and Providence County, Rhode Island
The bedrock geology of the 7.5-minute Uxbridge quadrangle consists of Neoproterozoic metamorphic and igneous rocks of the Avalon zone. In this area, rocks of the Avalon zone lie within the core of the Milford antiform, south and east of the terrane-bounding Bloody Bluff fault zone. Permian pegmatite dikes and quartz veins occur throughout the quadrangle. The oldest metasedimentary rocks include the Blackstone Group, which represents a Neoproterozoic peri-Gondwanan marginal shelf sequence. The metasedimentary rocks are intruded by Neoproterozoic arc-related plutonic rocks of the Rhode Island batholith. This report presents mapping by G.J. Walsh. The complete report consists of a map, text pamphlet, and GIS database. The map and text pamphlet are available only as downloadable files (see frame at right). The GIS database is available for download in ESRI™ shapefile and Google Earth™ formats, and includes contacts of bedrock geologic units, faults, outcrops, structural geologic information, geochemical data, and photographs.
Geologic map of the Colombo Quadrangle of the Moon
Relative ages of structures and geologic units have been determined from intersection and apparent overlap relations and from morphologic freshness reflecting degree of preservation. The fivefold crater-age sequence is based on the classification of Shoemaker and Hackman (1962 ), and corresponds broadly to a modified classification of Pohn and Offield (1970) and Offield (1971) . Rock units in the quadrangle are provisionally correlated with time-stratigraphic units first de scribed in and near the Imbrium basin (Shoemaker, 1962 a, b; Shoemaker and Hackman, 1962 , Shoemaker and others, 1963) and subsequently recognized elsewhere on the near side of the Moon (McCauley, 1967 ; Wilhelms , 1970; Wilhelms and McCauley, 1971).
Geologic map of the Louellen quadrangle, southeastern Kentucky
Explore the source record for details and available documents.
Geologic map of the Handshoe quadrangle, eastern Kentucky
Explore the source record for details and available documents.
Geologic map of the Tiptop quadrangle, eastern Kentucky
Explore the source record for details and available documents.
Bedrock geologic map of the Norfolk quadrangle, Connecticut
Explore the source record for details and available documents.
Geologic map of the Bledsoe quadrangle, southeastern Kentucky
Explore the source record for details and available documents.