A geothermal potential study for Washington State, just published by the Division of Geology and Earth Resources of the state's Department of Natural Resources, includes discussion of the Mount Baker area.. The Geothermal Favorability Model of Washington State, by D. E. Boschmann, J. L. Czajkowski, and J. D. Bowman (2014) is available on line:
( http://www.dnr.wa.gov/publications/ger_ofr2014-02_geothermal_favorability.pdf )
The Mount Baker portion of the study focused on the Baker Hot Spring area between Mount Baker and Baker Lake Reservoir on the east side of the mountain, as that is where the only surface expression of heat is known. There is also some speculation on the potential within the Kulshan caldera, between the volcano and Mount Shuksan.
Study summary: Geographic Information System (GIS) modeling of statewide heat, permeability, and infrastructure data, including volcanic centers, faults, earthquakes, temperature-gradient wells, thermal springs, young silicic intrusive rocks, and transmission lines produced layers showing relative geothermal favorability in Washington State. Regional modeling like this is one way to reduce costs in geothermal exploration by helping to more precisely locate areas worthy of additional research.
The entire discussion from the Baker section follows. The upshot is that while there may be considerable potential, infrastructure costs would be very high, and developement would be limited because the one of the most likely areas, within the Kulshan caldera, lies in the protected Mount Baker wilderness area.
The Mount Baker volcano and surrounding area have received considerable attention due to the presence of thermal features and young volcanic centers. Exploration activities have included detailed geologic mapping, spring sampling, geophysical surveys, soil mercury measurements, and limited temperature gradient drilling (Korosec, 1984). Chemical geothermometry of Baker Hot Springs suggests that reservoir equilibrium temperature of this system may reach as high as 150° to 170°C (Korosec, 1984). In 1983, a 140 - meter-deep (460 ft) temperature-gradient well was drilled near Baker Hot Springs. It had a bottomhole temperature of 48°C and a geothermal gradient between 200° and 309°C/km (Czajkowski and others, 2014c). However, this gradient is likely affected by hot spring circulation and may not represent a typical background value for the area.
Our modeled geothermal resource potential values near the Mount Baker/Kulshan Caldera suggest elevated resource potential, most notably in the area surrounding Kulshan Caldera (Fig. 6A) where no geothermal exploration has been performed to date. Kulshan Caldera is an oblate ~13-square-mile Pleistocene volcanic center located ~3.7 miles to the northeast of Mount Baker. Several Pleistocene andesite to rhyodacite vents and domes are located within the margins of the caldera, and late Pliocene to Pleistocene silicic intrusions are common in the surrounding area (Hildreth and others, 2003). However, our geothermal favorability model suggests that exploration for geothermal resources in this area would be unfavorable once transmission line proximity and elevation restrictions are considered (Fig. 6B). Further, much of the area with elevated resource potential lies within the Mount Baker Wilderness Area and is likely protected from any type of development.
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