A continental crustal model and its geothermal implications |
| |
| Authors: | Scott B Smithson Edward R Decker |
| |
| Institution: | Department of Geology, University of Wyoming, Laramie, Wyo. USA |
| |
| Abstract: | The following crustal model based on realistic estimates of metamorphic rock volumes and H2O content is proposed as a basis for geothermal calculations: (1) a surface zone of intermediate metamorphic rocks containing granitic intrusions and grading downward into (2) a more felsic migmatite zone, (3) a lower crustal zone of approximately andesitic composition crystallized in granulite or possibly amphibolite facies. Heat production values and thickness for the three zones are 3 HGU, 5 HGU, 0.5–1.5 HGU and 8, 8, and 18 km respectively. If the surface heat flow is 1.2 HFU, the model predicts a temperature of only 407°C at the Moho and an upper mantle heat flow of 0.3–0.5 HFU. The low temperatures resulting from this model rule out a seismic low-velocity zone in the crust produced by thermal effects. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
