Geologic contacts

Junctions of two different rock formations varying by type or age of rock, including faults, unconformities, and bedding planes.
This category is also used for contacts (geologic).
Subtopics:
Unconformities (8 items)
Related topics:

12 results listed by similarity [list alphabetically]
Interpretation of the elevation of the coastal-plain unconformity derived from seismic data collected within the New York Bight by the U.S. Geological Survey, 1995 - 1998 (Grid, UTM Zone 18N, WGS84 and Esri polyline shapefile, Geographic, WGS84)

Mapping the elevation of the coastal-plain unconformity is useful for delineating the geologic framework of the New York Bight inner-continental shelf. This in turn aids in understanding the stratigraphic evolution of the inner-continental shelf, the regional sediment transport system, and the influence of the inner-shelf framework on coastal processes. The grid showing structure of the coastal-plain unconformity is an important factor in the framework of the coastal region.

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Thickness of Quaternary seismic stratigraphic units offshore of the Delmarva Peninsula, including Maryland and Virginia state waters

Geologic structure and isopach maps were constructed by interpreting over 19.890 trackline kilometers of co-located multichannel boomer, sparker and chirp seismic reflection profiles from the continental shelf of the Delmarva Peninsula, including Maryland and Virginia state waters. In this region, Brothers and others (2020) interpret 12 seismic units and 11 regional unconformities. They interpret the infilled channels as Late Tertiary and Quaternary courses of the Susquehanna, Potomac, Rappahannock, York ...

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Elevation of the late Wisconsinan to early Holocene regressive unconformity (Ur) offshore of western and southern Martha's Vineyard and north of Nantucket, Massachusetts

Geologic, sediment texture, and physiographic zone maps characterize the sea floor south and west of Martha's Vineyard and north of Nantucket, Massachusetts. These maps were derived from interpretations of seismic-reflection profiles, high-resolution bathymetry, acoustic-backscatter intensity, bottom photographs, and surficial sediment samples. The interpretation of the seismic stratigraphy and mapping of glacial and Holocene marine units provided a foundation on which the surficial maps were created. This ...

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Holocene fluvial and estuarine (Qfe) and nearshore marine (Qmn) sediment thickness offshore of western and southern Martha's Vineyard and north of Nantucket, Massachusetts

Geologic, sediment texture, and physiographic zone maps characterize the sea floor south and west of Martha's Vineyard and north of Nantucket, Massachusetts. These maps were derived from interpretations of seismic-reflection profiles, high-resolution bathymetry, acoustic-backscatter intensity, bottom photographs, and surficial sediment samples. The interpretation of the seismic stratigraphy and mapping of glacial and Holocene marine units provided a foundation on which the surficial maps were created. This ...

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Elevation of paleochannel unconformities underlying the inner shelf of Long Bay (Grid)

In 1999, the U.S. Geological Survey (USGS), in partnership with the South Carolina Sea Grant Consortium, began a study to investigate processes affecting shoreline change along the northern coast of South Carolina, focusing on the Grand Strand region. Previous work along the U.S. Atlantic coast shows that the structure and composition of older geologic strata located seaward of the coast heavily influences the coastal behavior of areas with limited sediment supply, such as the Grand Strand. By defining this ...

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Elevation of the regional transgressive unconformity underlying the inner shelf of Long Bay (Grid; transgr_grd)

In 1999, the U.S. Geological Survey (USGS), in partnership with the South Carolina Sea Grant Consortium, began a study to investigate processes affecting shoreline change along the northern coast of South Carolina, focusing on the Grand Strand region. Previous work along the U.S. Atlantic coast shows that the structure and composition of older geologic strata located seaward of the coast heavily influences the coastal behavior of areas with limited sediment supply, such as the Grand Strand. By defining this ...

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Elevation of the late-Wisconsinan regressive unconformity beneath the Massachusetts inner continental shelf between Nahant and Northern Cape Cod Bay (urelev Esri binary grid; UTM, Zone 19N, WGS 84)

These data are qualitatively derived interpretive polygon shapefiles and selected source raster data defining surficial geology, sediment type and distribution, and physiographic zones of the sea floor from Nahant to Northern Cape Cod Bay. Much of the geophysical data used to create the interpretive layers were collected under a cooperative agreement among the Massachusetts Office of Coastal Zone Management (CZM), the U.S. Geological Survey (USGS), Coastal and Marine Geology Program, the National Oceanic ...

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Elevation of the Holocene transgressive unconformity beneath the Massachusetts inner continental shelf between Nahant and Northern Cape Cod Bay (utelev Esri binary grid; UTM, Zone 19N, WGS 84)

These data are qualitatively derived interpretive polygon shapefiles and selected source raster data defining surficial geology, sediment type and distribution, and physiographic zones of the sea floor from Nahant to Northern Cape Cod Bay. Much of the geophysical data used to create the interpretive layers were collected under a cooperative agreement among the Massachusetts Office of Coastal Zone Management (CZM), the U.S. Geological Survey (USGS), Coastal and Marine Geology Program, the National Oceanic ...

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100-meter grid representing the coastal plain unconformity (in meters) beneath the inner-continental shelf offshore of Fire Island, NY (FI_CPUN, UTM Zone 18N, WGS 84, Esri Binary Grid)

The U.S. Geological Survey (USGS) mapped approximately 336 square kilometers of the lower shoreface and inner-continental shelf offshore of Fire Island, New York in 2011 using interferometric sonar and high-resolution chirp seismic-reflection systems. This report presents maps of bathymetry, acoustic backscatter, the coastal plain unconformity, the Holocene marine transgressive surface and modern sediment thickness. These spatial data support research on the Quaternary evolution of the Fire Island ...

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Hillshaded-relief image produced from the late Wisconsinan to early Holocene regressive unconformity (Ur) beneath Vineyard and western Nantucket Sounds, Massachusetts (GeoTIFF Image; UTM, Zone 19N, WGS 84)

Geologic, sediment texture, and physiographic zone maps characterize the sea floor of Vineyard and western Nantucket Sounds, Massachusetts. These maps were derived from interpretations of seismic-reflection profiles, high-resolution bathymetry, acoustic-backscatter intensity, bottom photographs, and surficial sediment samples. The interpretation of the seismic stratigraphy and mapping of glacial and Holocene marine units provided a foundation on which the surficial maps were created. This mapping is a ...

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Depth to Quaternary regional unconformities offshore of the Delmarva Peninsula, including Maryland and Virginia state waters

Geologic structure and isopach maps were constructed by interpreting over 19,890 trackline kilometers of co-located multichannel boomer, sparker and chirp seismic reflection profiles from the continental shelf of the Delmarva Peninsula, including Maryland and Virginia state waters. In this region, Brothers and others (2020) interpret 12 seismic units and 11 regional unconformities. They interpret the infilled channels as Late Tertiary and Quaternary courses of the Susquehanna, Potomac, Rappahannock, York ...

Info
Elevation of the late Wisconsinan to early Holocene regressive unconformity (Ur) beneath Vineyard and western Nantucket Sounds, Massachusetts (Esri binary grid; UTM, Zone 19N, WGS 84)

Geologic, sediment texture, and physiographic zone maps characterize the sea floor of Vineyard and western Nantucket Sounds, Massachusetts. These maps were derived from interpretations of seismic-reflection profiles, high-resolution bathymetry, acoustic-backscatter intensity, bottom photographs, and surficial sediment samples. The interpretation of the seismic stratigraphy and mapping of glacial and Holocene marine units provided a foundation on which the surficial maps were created. This mapping is a ...

Info