This layer contains data concerning the location and characteristics of unconsolidated Quaternary deposits within Frederick county. This geodatabase contains geologic data from Frederick County, Maryland. Data from several geologic quadrangles and two regional scale geologic maps were incorporated into the regional scale geologic feature classes in this geodatabase. Because of the scale of this map, some features were generalized slightly from the quad scale data. Additionally, some corrections were made for accuracy, such as edge matching to resolve "border faults". The source data for this map and geodatabase come from maps published by the Maryland Geological Survey from 2001 to the present, as well as one map published in cooperation with the United States Geological Survey. The source maps are Buckeystown (2001), Catoctin Furnace (2004), Frederick (2004), New Windsor (2004), Point of Rocks (2004), Walkersville (2004), Woodsboro (2004), Middletown (2005), Union Bridge (2006), Funkstown (2009), Keedysville, Shepherdstown, Charlestown, and Harpers Ferry (2009), Myersville and Smithsburg (2009), Hagerstown (2013), Mason and Dixon (2013), Clear Spring and Hedgesville (2014), Williamsport (2014), Blue Ridge Summit (2021, in review), Emmitsburg and Taneytown (2021, in review), all 1:24000 quadrangle scale, as well as portions of two regional maps: Geologic Map of Garrett, Allegany, and Western Washington Counties, Maryland (2013), and Geologic Map of the Frederick 30' x 60' Quadrangle, Maryland, Virginia, and West Virginia (USGS, 2007). The GIS data from the referenced maps were mosaiced in Arc Map, corrected for accuracy across quad boundaries, merged to form a continuous dataset and clipped to the extent of Frederick County. Feature level metadata are included, which contain field descriptions for each feature class. This is a small scale dataset, appropriate for 1:100,000 regional scale. Quad scale data are suggested for display or analysis that requires a larger scale. This dataset is prepared for compliance with the USGS GeMS database standard. Last Updated: 06/01/2022

This layer contains data concerning field measurements of inclined bedding, structure features like fracture, cleavage, and other field measurements within Washington county. This geodatabase contains geologic data from Washington County, Maryland. Data from several geologic quadrangles and two regional scale geologic maps were incorporated into the regional scale geologic feature classes in this geodatabase. Because of the scale of this map, some features were generalized slightly from the quad scale data. Additionally, some corrections were made for accuracy, such as edge matching to resolve "border faults". The source data for this map and geodatabase come from maps published by the Maryland Geological Survey from 2001 to the present, as well as one map published in cooperation with the United States Geological Survey. The source maps are Buckeystown (2001), Catoctin Furnace (2004), Frederick (2004), New Windsor (2004), Point of Rocks (2004), Walkersville (2004), Woodsboro (2004), Middletown (2005), Union Bridge (2006), Funkstown (2009), Keedysville, Shepherdstown, Charlestown, and Harpers Ferry (2009), Myersville and Smithsburg (2009), Hagerstown (2013), Mason and Dixon (2013), Clear Spring and Hedgesville (2014), Williamsport (2014), Blue Ridge Summit (2021, in review), Emmitsburg and Taneytown (2021, in review), all 1:24000 quadrangle scale, as well as portions of two regional maps: Geologic Map of Garrett, Allegany, and Western Washington Counties, Maryland (2013), and Geologic Map of the Frederick 30' x 60' Quadrangle, Maryland, Virginia, and West Virginia (USGS, 2007). The GIS data from the referenced maps were mosaiced in Arc Map, corrected for accuracy across quad boundaries, merged to form a continuous dataset and clipped to the extent of Washington County. Feature level metadata are included, which contain field descriptions for each feature class. This is a small scale dataset, appropriate for 1:100,000 regional scale. Quad scale data are suggested for display or analysis that requires a larger scale. This dataset is prepared for compliance with the USGS GeMS database standard. Last Updated: 06/01/2022

This layer contains data concerning the location and characteristics of bedrock, mappable geologic units, within Frederick county. This geodatabase contains geologic data from Frederick County, Maryland. Data from several geologic quadrangles and two regional scale geologic maps were incorporated into the regional scale geologic feature classes in this geodatabase. Because of the scale of this map, some features were generalized slightly from the quad scale data. Additionally, some corrections were made for accuracy, such as edge matching to resolve "border faults". The source data for this map and geodatabase come from maps published by the Maryland Geological Survey from 2001 to the present, as well as one map published in cooperation with the United States Geological Survey. The source maps are Buckeystown (2001), Catoctin Furnace (2004), Frederick (2004), New Windsor (2004), Point of Rocks (2004), Walkersville (2004), Woodsboro (2004), Middletown (2005), Union Bridge (2006), Funkstown (2009), Keedysville, Shepherdstown, Charlestown, and Harpers Ferry (2009), Myersville and Smithsburg (2009), Hagerstown (2013), Mason and Dixon (2013), Clear Spring and Hedgesville (2014), Williamsport (2014), Blue Ridge Summit (2021, in review), Emmitsburg and Taneytown (2021, in review), all 1:24000 quadrangle scale, as well as portions of two regional maps: Geologic Map of Garrett, Allegany, and Western Washington Counties, Maryland (2013), and Geologic Map of the Frederick 30' x 60' Quadrangle, Maryland, Virginia, and West Virginia (USGS, 2007). The GIS data from the referenced maps were mosaiced in Arc Map, corrected for accuracy across quad boundaries, merged to form a continuous dataset and clipped to the extent of Frederick County. Feature level metadata are included, which contain field descriptions for each feature class. This is a small scale dataset, appropriate for 1:100,000 regional scale. Quad scale data are suggested for display or analysis that requires a larger scale. This dataset is prepared for compliance with the USGS GeMS database standard. Last Updated: 06/01/2022

This layer contains data concerning the location and characteristics of contacts and faults within Frederick county. This geodatabase contains geologic data from Frederick County, Maryland. Data from several geologic quadrangles and two regional scale geologic maps were incorporated into the regional scale geologic feature classes in this geodatabase. Because of the scale of this map, some features were generalized slightly from the quad scale data. Additionally, some corrections were made for accuracy, such as edge matching to resolve "border faults". The source data for this map and geodatabase come from maps published by the Maryland Geological Survey from 2001 to the present, as well as one map published in cooperation with the United States Geological Survey. The source maps are Buckeystown (2001), Catoctin Furnace (2004), Frederick (2004), New Windsor (2004), Point of Rocks (2004), Walkersville (2004), Woodsboro (2004), Middletown (2005), Union Bridge (2006), Funkstown (2009), Keedysville, Shepherdstown, Charlestown, and Harpers Ferry (2009), Myersville and Smithsburg (2009), Hagerstown (2013), Mason and Dixon (2013), Clear Spring and Hedgesville (2014), Williamsport (2014), Blue Ridge Summit (2021, in review), Emmitsburg and Taneytown (2021, in review), all 1:24000 quadrangle scale, as well as portions of two regional maps: Geologic Map of Garrett, Allegany, and Western Washington Counties, Maryland (2013), and Geologic Map of the Frederick 30' x 60' Quadrangle, Maryland, Virginia, and West Virginia (USGS, 2007). The GIS data from the referenced maps were mosaiced in Arc Map, corrected for accuracy across quad boundaries, merged to form a continuous dataset and clipped to the extent of Frederick County. Feature level metadata are included, which contain field descriptions for each feature class. This is a small scale dataset, appropriate for 1:100,000 regional scale. Quad scale data are suggested for display or analysis that requires a larger scale. This dataset is prepared for compliance with the USGS GeMS database standard. Last Updated: 06/01/2022

This layer contains data concerning field measurements of inclined bedding, structure features like fracture, cleavage, and other field measurements within Frederick county. This geodatabase contains geologic data from Frederick and County, Maryland. Data from several geologic quadrangles and two regional scale geologic maps were incorporated into the regional scale geologic feature classes in this geodatabase. Because of the scale of this map, some features were generalized slightly from the quad scale data. Additionally, some corrections were made for accuracy, such as edge matching to resolve "border faults". The source data for this map and geodatabase come from maps published by the Maryland Geological Survey from 2001 to the present, as well as one map published in cooperation with the United States Geological Survey. The source maps are Buckeystown (2001), Catoctin Furnace (2004), Frederick (2004), New Windsor (2004), Point of Rocks (2004), Walkersville (2004), Woodsboro (2004), Middletown (2005), Union Bridge (2006), Funkstown (2009), Keedysville, Shepherdstown, Charlestown, and Harpers Ferry (2009), Myersville and Smithsburg (2009), Hagerstown (2013), Mason and Dixon (2013), Clear Spring and Hedgesville (2014), Williamsport (2014), Blue Ridge Summit (2021, in review), Emmitsburg and Taneytown (2021, in review), all 1:24000 quadrangle scale, as well as portions of two regional maps: Geologic Map of Garrett, Allegany, and Western Washington Counties, Maryland (2013), and Geologic Map of the Frederick 30' x 60' Quadrangle, Maryland, Virginia, and West Virginia (USGS, 2007). The GIS data from the referenced maps were mosaiced in Arc Map, corrected for accuracy across quad boundaries, merged to form a continuous dataset and clipped to the extent of Frederick County. Feature level metadata are included, which contain field descriptions for each feature class. This is a small scale dataset, appropriate for 1:100,000 regional scale. Quad scale data are suggested for display or analysis that requires a larger scale. This dataset is prepared for compliance with the USGS GeMS database standard. Last Updated: 06/01/2022

This digital data set describes surficial geology of the conterminous United States. The data set was generated from a U.S. Geological Survey 1:7,500,000-scale map of surficial geology published as part of the U.S. Geological Survey National Atlas map series.

This digital dataset compiles a 3-layer geologic model of the conterminous United States by mapping the altitude of three surfaces: land surface, top of bedrock, and top of basement. These surfaces are mapped through the compilation and synthesis of published stratigraphic horizons from numerous topical studies. The mapped surfaces create a 3-layer geologic model with three geomaterials-based subdivisions: unconsolidated to weakly consolidated sediment; layered consolidated rock strata that constitute bedrock, and crystalline basement, consisting of either igneous, metamorphic, or highly deformed rocks. Compilation of subsurface data from published reports involved standard techniques within a geographic information system (GIS) including digitizing contour lines, gridding the contoured data, sampling the resultant grids at regular intervals, and attribution of the dataset. However, data compilation and synthesis is highly dependent on the definition of the informal terms “bedrock” and “basement”, terms which may describe different ages or types of rock in different places. The digital dataset consists of a single polygon feature class which contains an array of square polygonal cells that are 2.5 km m in x and y dimensions. These polygonal cells multiple attributes including x-y location, altitude of the three mapped layers at each x-y location, the published data source from which each surface altitude was compiled, and an attribute that allows for spatially varying definitions of the bedrock and basement units. The spatial data are linked through unique identifiers to non-spatial tables that describe the sources of geologic information and a glossary of terms used to describe bedrock and basement type.

This layer contains detailed outlines of Maryland counties. The Maryland land county boundaries were built using political county boundaries and the National Hydrology Data (NHD). Land boundaries are a key geographic featue in our mapping process.