Heat flow and seismicity patterns in the vicinity of the eastern Snake River Plain, Idaho
- Southern Methodist Univ., Dallas, TX (United States). Dept. of Geological Sciences
New heat flow data and thermal modeling are used to calculate crustal temperatures in and adjacent to the eastern Snake River Plain (SRP). The estimated crustal temperature are then used to investigate the relationship between crustal strength and the observed parabolic pattern of seismicity around the SRP. Heat flow below the SRP aquifer in deep wells on the Idaho National Engineering Laboratory (INEL) site near the northern margin of the SRP is 107 [plus minus] 15 mWm[sup [minus]2]. Heat flow values from deep wells on both the northern and southern margins of the eastern SRP average 100 [plus minus] 15 mWm[sup [minus]2]. 2-D finite-difference thermal models were developed to fit seismic and heat flow data in the vicinity of the SRP. The models have a shallow silicic magma chamber that is as wide as the SRP. The silicic chamber is underlain by mafic heat sources in the middle to lower crust and in the upper mantle. The heat flow data are best fit by models with deep heat sources that are wider than the SRP. These results are consistent with the presence of young basaltic centers that have been observed outside the SRP. The temperature from the authors thermal models were used to calculate strength envelopes for the crust in the SRP/Basin and Range region. The weakest part of the crust is along the edge of the Basin and Range, where it is heated by the SRP; thus the boundary to the two provinces may be a zone of weak coupling. Their modeling indicates that it is difficult to explain the earthquake pattern in the vicinity of the SRP as a thermomechanical effect related to the passage of the Yellowstone hot spot.
- OSTI ID:
- 5289879
- Report Number(s):
- CONF-9305259-; CODEN: GAAPBC
- Journal Information:
- Geological Society of America, Abstracts with Programs; (United States), Vol. 25:5; Conference: 89. annual meeting of the Cordilleran Section and the 46th annual meeting of the Rocky Mountain Section of the Geological Society of America (GSA), Reno, NV (United States), 19-21 May 1993; ISSN 0016-7592
- Country of Publication:
- United States
- Language:
- English
Similar Records
Origin of deep crustal reflections: Implications of coincident seismic refraction and reflection data in Nevada
Geothermal setting and simple heat conduction models for the Long Valley caldera
Related Subjects
15 GEOTHERMAL ENERGY
EARTH CRUST
HEAT FLOW
TEMPERATURE GRADIENTS
SNAKE RIVER PLAIN
SEISMICITY
EARTHQUAKES
IDAHO
MAGMA SYSTEMS
TEMPERATURE MEASUREMENT
DEVELOPED COUNTRIES
GEOTHERMAL SYSTEMS
NORTH AMERICA
SEISMIC EVENTS
USA
580000* - Geosciences
150200 - Geology & Hydrology of Geothermal Systems