Geology and geochemistry of the Geyser Bight Geothermal Area, Umnak Island, Aleutian Islands, Alaska

Technical Report · Mon Oct 01 00:00:00 EDT 1990

DOI:https://doi.org/10.2172/6193109· OSTI ID:6193109

Nye, C J ^[1]; Motyka, R J ^[2]; Turner, D L ^[3]; Liss, S A ^[4]

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1. Alaska Univ., Fairbanks, AK (USA). Geophysical Inst. Alaska Dept. of Natural Resources, Fairbanks, AK (USA). Div. of Geological and Geophysical Surveys
2. Alaska Dept. of Natural Resources, Juneau, AK (USA). Div. of Geological and Geophysical Surveys
3. Alaska Univ., Fairbanks, AK (USA). Geophysical Inst.
4. Alaska Dept. of Natural Resources, Fairba

The Geyser Bight geothermal area is located on Umnak Island in the central Aleutian Islands. It contains one of the hottest and most extensive areas of thermal springs and fumaroles in Alaska, and is only documented site in Alaska with geysers. The zone of hot springs and fumaroles lies at the head of Geyser Creek, 5 km up a broad, flat, alluvial valley from Geyser Bight. At present central Umnak is remote and undeveloped. This report describes results of a combined program of geologic mapping, K-Ar dating, detailed description of hot springs, petrology and geochemistry of volcanic and plutonic rock units, and chemistry of geothermal fluids. Our mapping documents the presence of plutonic rock much closer to the area of hotsprings and fumaroles than previously known, thus increasing the probability that plutonic rock may host the geothermal system. K-Ar dating of 23 samples provides a time framework for the eruptive history of volcanic rocks as well as a plutonic cooling age.

• Research Organization: Alaska Univ., Fairbanks, AK (USA). Geophysical Inst.; Alaska Dept. of Natural Resources, Fairbanks, AK (USA). Div. of Geological and Geophysical Surveys; Alaska Dept. of Natural Resources, Juneau, AK (USA). Div. of Geological and Geophysical Surveys
• Sponsoring Organization: DOE/CE
• DOE Contract Number: FG07-88ID12742; FG07-88ID12744
• OSTI ID: 6193109
• Report Number(s): DOE/ID/12742-1; ON: DE91006304
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
GEYSERS GEOTHERMAL FIELD
GEOCHEMISTRY
GEOLOGY
GEOTHERMAL FLUIDS
HEAT FLOW
PLUTONIC ROCKS
PROGRESS REPORT
VOLCANIC ROCKS
WATER CHEMISTRY
CHEMISTRY
DOCUMENT TYPES
FLUIDS
GEOTHERMAL FIELDS
IGNEOUS ROCKS
ROCKS
Geothermal Legacy
150200* - Geology & Hydrology of Geothermal Systems
150302 - Geothermal Exploration & Exploration Technology- Geochemical Techniques & Surveys