Hydrothermal system at Newberry Volcano, Oregon

Journal Article · Sat Sep 10 00:00:00 EDT 1988 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JB093iB09p10149· OSTI ID:6874777

Sammel, E A; Ingebritsen, S E; Mariner, R H

Results of recent geological and geophysical studies at Newberry Volcano have been incorporated into conceptual and numerical models of a magma-based hydrothermal system. Numerical simulations begin with emplacement of a small magma body, the presumed source of silicic eruptions at Newberry that began about 10,000 B.P., into a thermal regime representing 100,000 years of cooling of a large underlying intrusion. Simulated flow patterns and thermal histories for three sets of hypothetical permeability values are compatible with data from four geothermal drill holes on the volcano. Meteoric recharge cools the caldera-fill deposits, but thermal water moving up a central conduit representing a permeable volcanic vent produces temperatures close to those observed in drill holes within the caldera. Meteoric recharge from the caldera moves down the flanks and creates a near-isothermal zone that extends several hundred meters below the water table, producing temperature profiles similar to those observed in drill holes on the flanks. The temperatures observed in drill holes on the flanks are not influenced by the postulated Holocene magma body. The elevated temperature gradients measured in the lower portions of these holes may be related to the cumulative effect of older intrusions. The models also indicate that meteoric recharge to the deep hydrothermal system probably originates within or near the caldera. Relatively low fluid velocities at depth suggest that at least a significant fraction of the thermal fluid may be very old.

• Research Organization: U.S. Geological Survey, Menlo Park, California
• OSTI ID: 6874777
• Journal Information: J. Geophys. Res.; (United States), Vol. 93:B9
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
CASCADE MOUNTAINS
VOLCANISM
VOLCANOES
GEOLOGIC MODELS
HYDROTHERMAL SYSTEMS
MAGMA SYSTEMS
GEOTHERMAL ENERGY
GEOTHERMAL FLUIDS
GEOTHERMAL GRADIENTS
OREGON
SIMULATION
ENERGY
ENERGY SOURCES
ENERGY SYSTEMS
FEDERAL REGION X
FLUIDS
GEOTHERMAL SYSTEMS
MOUNTAINS
NORTH AMERICA
RENEWABLE ENERGY SOURCES
TEMPERATURE GRADIENTS
USA
150200* - Geology & Hydrology of Geothermal Systems