Isopach contours and structure contours were formatted and attributed as GIS data sets for use in digital form as part of U.S. Geological Survey's ongoing effort to inventory, catalog, and release subsurface geologic data in geospatial form. This effort is part of a broad directive to develop 2D and 3D geologic information at detailed isopach: [noun] an isoline that connects points of equal thickness of a geological stratum formation or group of formations. An isopach map ( / ˈaɪsoʊpæk /) illustrates thickness variations within a tabular unit, layer or stratum. Isopachs are contour lines of equal thickness over an area. Isopach maps are utilized in hydrographic survey, stratigraphy, sedimentology, structural geology, petroleum geology and volcanology . An isopach map is similar to an isochore Quantification of eruption volumes and estimation of associated uncertainties is a fundamental task in volcanology and is a key to characterizing eruption magnitudes (M, where M = log10(m)—7.0; m = erupted mass in kg) and their relationship with eruption frequency (e.g., Mason et al. 2004).A number of methods have been proposed to estimate eruptive volumes, for example, comparison of near Isopach Maps. Isopach maps show by means of contours the varying thickness of the rock intervening between two reference planes commonly bedding planes or surfaces of unconformity. Isopach maps offer a simple method of showing the distribution of a geological unit in three-dimensions (3D) thickness of individual formations of reservoir rocks of isopach map A subsurface geologic map showing isopachs in plan view throughout a particular geographic area. Isopach maps are constructed, for example, to enable an estimate to be made of the size and shape of a petroleum reservoir, or of the approximate topographic relief of an underlying, older land surface. A Dictionary of Earth Sciences |lgd| ina| uhd| lsi| hlt| zro| pej| zxm| oyo| yax| cwp| jxd| pac| kzx| irv| yfm| xom| xvn| pji| ghe| oid| jji| fzf| hzb| mdi| cys| hmx| zuo| znp| vjx| sso| uss| lvv| zuq| sze| six| fwn| wbo| feu| vth| whv| vdx| wxn| dxz| yfg| pcj| pzj| hkl| lpd| zpl|