Tectonic implications of the heat flow of the western Snake River Plain, Idaho

Research Article| December 01, 1978 Tectonic implications of the heat flow of the western Snake River Plain, Idaho CHARLES A. BROTT; CHARLES A. BROTT 1Department of Geological Sciences, Southern Methodist University, Dallas, Texas 75275 Search for other works by this author on: GSW Google Scholar DAVID D. BLACKWELL; DAVID D. BLACKWELL 1Department of Geological Sciences, Southern Methodist University, Dallas, Texas 75275 Search for other works by this author on: GSW Google Scholar JOHN C. MITCHELL JOHN C. MITCHELL 2Idaho Department of Water Resources, Boise, Idaho 83707 Search for other works by this author on: GSW Google Scholar Author and Article Information CHARLES A. BROTT 1Department of Geological Sciences, Southern Methodist University, Dallas, Texas 75275 DAVID D. BLACKWELL 1Department of Geological Sciences, Southern Methodist University, Dallas, Texas 75275 JOHN C. MITCHELL 2Idaho Department of Water Resources, Boise, Idaho 83707 Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1978) 89 (12): 1697–1707. https://doi.org/10.1130/0016-7606(1978)89<1697:TIOTHF>2.0.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation CHARLES A. BROTT, DAVID D. BLACKWELL, JOHN C. MITCHELL; Tectonic implications of the heat flow of the western Snake River Plain, Idaho. GSA Bulletin 1978;; 89 (12): 1697–1707. doi: https://doi.org/10.1130/0016-7606(1978)89<1697:TIOTHF>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract Heat-flow values within the western Snake River Plain average about 1.7 µcal/cm2 sec, but even higher values are measured in granitic rocks along the margins of the Snake River Plain (2.5 µcal/cm2 sec or higher). The heat-flow distribution is related to the combined effects of crustal thermal refraction and a large, transient crustal heat source. A regional model consistent with the heat-flow pattern and other geophysical and geological data is described which assumes the emplacement of a large heat source (mafic intrusion?) under the western Snake River Plain about 10 to 15 m.y. ago. An anomaly of about 0.3 µcal/cm2 sec is predicted over the center of the heat source at the present time. The timing of the emplacement of the heat source corresponds with the age of voluminous silicic volcanism in the western Snake River Plain. A time-progressive thermal model is presented for the Snake River Plain which is consistent with the time progression of silicic volcanism. Based on the model, higher regional heat-flow values are predicted for the eastern Snake River Plain. Confirmation of the high regional heat-flow values is not possible in the bore holes available (200± m deep) because of regional circulation of cold ground water in the Snake Plain Aquifer. However, a close correlation between integrated crustal and upper mantle temperature and observed elevation changes along the axis of the Snake River Plain is strong support for the heat-flow model. The possibility of high heat flow in the eastern part of the Snake River Plain implies that the area may have significant geothermal potential in spite of the low surface heat flow. The regional aseismic warping observed in the eastern Snake River Plain can be interpreted as a thermal contraction phenomenon involving the crust and upper mantle. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.