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USGS · pp1879v1E

Guidelines for conducting reviews of geologic names and aquifer names in U.S. Geological Survey hydrogeologic maps and reports

Steven D. Craigg·Randall C. Orndorff
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Abstract

Introduction The U.S. Geological Survey (USGS) is officially charged with assessment of various aspects of geology and hydrogeology throughout the Nation. Hence, USGS publications adhere to broadly uniform procedures in the classification and nomenclature of geologic and hydrogeologic units. Responsibility for this uniformity is under the technical guidance of the Geologic Names Committee (GNC), which formulates general policy and advises on specific nomenclatural issues. Central to the GNC proceedings is the North American Stratigraphic Code (hereafter referred to as “the Code”) (North American Commission on Stratigraphic Nomenclature [NACSN], 2021). Geologic reports typically contain geologic maps and cross sections, geologic unit names, lithologic descriptions, and stratigraphic correlation charts, as well as results of drilling activities and structure-contour, depth-to-top, depth-to-base, or sediment-thickness maps. Groundwater-resource maps and other hydrogeologic maps and reports can also contain many of these same elements. Groundwater-resource reports rarely contain original geologic mapping, revisions of stratigraphic nomenclature, or redefinitions or changes in the ranks or ages of geologic units; however, these reports usually contain descriptions and classifications of hydrogeologic units, and they also may introduce new or modify existing aquifer nomenclature. The following general guidance is published for those designated as geologic and aquifer names reviewers.

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Steven D. Craigg, Randall C. Orndorff. 2023-07-07. Guidelines for conducting reviews of geologic names and aquifer names in U.S. Geological Survey hydrogeologic maps and reports. https://doi.org/10.3133/pp1879v1e

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