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(ˈaɪsəʊˌpæk) or


(Geological Science) geology a line on a map connecting points below which a particular rock stratum has the same thickness
[C20: from iso- + Greek pakhus thick, pakhutēs thickness]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈaɪ səˌpæk)

a line drawn on a map connecting all points of equal thickness of a particular geologic formation.
[1915–20; iso- + -pach < Greek páchos thickness]
i`so•pach′ous, adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
The diagenetic processes, noticed in carbonates of the Mughal Kot Formation, includes micritization, dolomitization, iron cementation, cementation (isopach), mechanical compaction, chemical compaction (stylolitization) and fracturing (but most are filled).
As described below, lithofacies and isopach maps were constructed from theavailablewellcontrol.
The isopach map (Figure 6(a)) shows thickest Maidiping-Canglangpu Formations to be located in the center of the Sichuan basin, where the thickness is about 450-1700 m higher than 0-600 m at any other place.
Major pyroclastics from this eruption cover areas of ~30,000[km.sup.2] (ignimbrite), ~140,000[km.sup.2] ([greater than or equal to]50cm tephra isopach), 530,000 [km.sup.2] ([greater than or equal to]20cm tephra isopach), 1,510,000[km.sup.2] ([greater than or equal to]10cm tephra isopach), and 2,500,000[km.sup.2] ([greater than or equal to]5cm tephra isopach).
This database was compiled using previously published isopach maps [42-46], ocean drilling results, and seismic reflection profiles archived in the NGDC as well as seismic data and isopach maps available as a part of the International Geological-Geophysical Atlas of the Pacific Ocean [47].
An isopach map of the Duperow Formation reveals that this unit thickens to the north with an overall change of 100 to 200 ft.
target, the Cline Shale in West Texas, is thought to have an isopach
Isopach maps of key reservoir intervals of interest, including the Marcellus and Utica (Point Pleasant) shale formations;
The ages of key bio- and lithostratigraphic levels were interpolated from radiocarbon-dated intervals, and isopach maps were constructed between the dated horizons.
Whether they are trying to track down isopach maps and seismic stratigraphy data that details the Upper Pliocene and Quaternary deposits in the South Caspian Basin or are simply trying to find content related to a known geological basin, they need sophisticated data at their fingertips.
where r is distance of the isopach from the crack, a is dimension of the crack, [theta] is angle of the isopach depending on r, a is total stress (loading), [[sigma].sub.xx], [[sigma].sub.yy], [[sigma].sub.xy] are main stresses in the direction of the axis x, y, xy.