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This GIS dataset is reproduced from “Hose, R.K., 1974, Geologic map of the Trout Creek SE quadrangle, Juab and Millard Counties, Utah: U.S. Geological Survey Miscellaneous Investigations Series Map I-827, 1 plate, scale 1:24,000.” The map covers one standard 7.5' quadrangle in west-central Utah. The GIS dataset was completed by Colin Andrew and Benjamin Barton, students at Brigham Young University, and final GIS review and preparation for public release were completed by Zach Anderson and Martha L. Jensen, GIS Analysts with the Utah Geological Survey (UGS).The UGS appreciates the volunteered time and effort of Brigham Young University students Colin Andrew and Benjamin Barton who produced the GIS data for this project under the guidance of Brigham Young University professor Eric Christiansen.The quadrangle area is in the Basin and Range physiographic province of west-central Utah and is dominated by north-south-trending mountain ranges and broad valleys. The ranges expose Permian through Devonian strata. Tertiary sedimentary rocks locally conceal the older strata. The structure reflects the Sevier fold-thrust belt and subsequent extensional tectonics. The valleys are filled with thick basin-fill deposits of diverse origin.This dataset was produced as part of a UGS multi-decade effort to provide statewide GIS data to the public, federal to local government agencies, educational groups, exploration and development companies, and other map users. The GIS dataset reproduces the original source map as close as reasonably possible; however, some geologic decisions were made to resolve cartographic issues such as attributing faults and folds. We changed some geologic line symbols to better match the UGS 2018 data model. While the map is considered a good representation of the geology of the map area, users should be aware that it was produced in 1974 and does not meet all modern cartographic, spatial control, or geologic standards. Line attributes and symbology were selected from current (2018) UGS schema and do not necessarily match the intent of the original map. Selected attributes most closely represent the general geologic interpretation depicted on the original map, but are not an exact match, as noted below.ContactsOriginal attributes are “Contact – Dotted where concealed.” These lines are now depicted as “Contact, well located.”Marker BedsFor marker beds in the Arcturus Formation. These lines are now depicted as “Marker bed, well located” or “Marker bed, concealed” with labels A, B, and D. In addition, for the Unconformity in the Ely Limestone of Hose and Reppening (1959), this line is now depicted as “Marker bed, well located” with the label U.Unknown FaultsOriginal attributes are “Fault – Dashed where poorly exposed or inferred; dotted where concealed; queried where doubtful. Bar and ball on downthrown side.” These lines are now depicted as “Fault, unknown, well located”; “Fault, unknown, approximately located”; or “Fault, unknown, concealed.” These faults are symbolized as normal faults per the UGS schema to match the appearance of the original map.General faultsLine types do not have a description in the explanation of the original map. Where ball and bar were not depicted along a fault on the original map, these lines are now depicted as “Fault, unknown, well located”; “Fault, unknown, approximately located”; “Fault, unknown, approximately located, queried”;or “Fault, unknown, concealed.”Thrust FaultsOriginal attributes are “Low-angle fault – Dashed where poorly exposed or inferred; dotted where concealed. Sawteeth on upper plate.” These lines are now depicted as “Fault, thrust, well located”; “Fault, thrust, approximately located”; or “Fault, thrust, concealed” where older rocks are faulted over younger rocks.Detachment FaultsOriginal attributes are “Low-angle fault – Dashed where poorly exposed or inferred; dotted where concealed. Sawteeth on upper plate.” These lines are now depicted as “Fault, detachment, well located”; “Fault, detachment, approximately located”; or “Fault, detachment, concealed” where younger rocks are faulted over older rocks.AnticlineOriginal attributes are “Anticline – Showing approximate position of axial trace. Dotted where concealed.” These lines are now depicted as "Fold, anticline, upright, well located”;or "Fold, anticline, upright, concealed."Crest of minor anticlineOriginal attributes are “Crest of minor anticline.” These lines have been converted to "Fold, anticline, upright, well located”; or "Fold, anticline, upright, concealed."SynclineOriginal attributes are “Syncline – Showing approximate position of axial trace; dotted where concealed.” These lines are now depicted as “Fold, syncline, upright, well located”;or “Fold, syncline, upright, concealed.” Overturned synclineOriginal attributes are “Overturned syncline – Showing approximate trace of axial surface.” These lines are now depicted as “Fold, syncline, overturned, well located”; or “Fold syncline, overturned, concealed.”SynformOriginal attributes are “Synform– In upside-down beds; showing approximate position of axial trace; dotted where concealed.” These lines are now depicted as “Fold, anticline, synformal, well located”; or “Fold, anticline, synformal, concealed.”Trough of minor synclineOriginal attributes are “Trough of minor syncline.” These lines are now depicted as “Fold, syncline, upright, well located” or “Fold, syncline, upright, concealed.” Units – Descriptions/Names/AgesMap is not modified from original source map even in locations where newer interpretations may exist. |