Core Analysis At Long Valley Caldera Geothermal Area (Smith & Suemnicht, 1991)
From Open Energy Information
Exploration Activity: Core Analysis At Long Valley Caldera Geothermal Area (Smith & Suemnicht, 1991)
|Exploration Activity Details|
|Location||Long Valley Caldera Geothermal Area|
|Exploration Technique||Core Analysis|
|Activity Date||1985 - 1988|
Sorey et al. (1991) integrated information from previous scientific and private industry investigations with new data obtained from fluid sampling, test drilling, and geological and geophysical studies conducted between 1985-1988 into a comprehensive conceptual model of the present-day hydrothermal flow system at Long Valley caldera. Lithology and temperature gradient data from wells drilled prior to 1988 are summarized in detail in the compilation, which includes information from numerous wells described in previous studies, and data from many of the wells are available online through the U.S. Geological Survey (Farrar et al., 2010). Thermal conductivity, XRD, and isotopic analyses of core cuttings from several of the wells discussed have been completed in several studies, and seem to prove useful in most cases (Flexser, 1991; Goff et al., 1991; Smith and Suemnicht, 1991). Results from these studies are also summarized in Sorey et al. (1991). Relevant data from chemical and isotopic studies published during the same year are also considered in the review.
"Sample for the present investigation consist of drill core and cuttings from all lithologic units identified in LVEW, cuttings from volcanic rocks in LV 13-21, core samples of Early Rhyolite and Bishop Tuff from LV13-26 and core samples of Bishop Tuff from SF38-32, LV48-29 and LV66-28 (Figs. 1 and 2). Surface samples of Early Rhyolite, Bishop Tuff and Paleozoic metasediments (Fig. 1) were also selected for comparative analysis and processed by the same procedures as the well samples. This oxygen isotope and fluid inclusion study has allowed us to determine the pathways of fluid circulation, set limits on the thermal regime, and link the source of the heat to prolonged volcanic activity."
- Brian M. Smith, Gene A. Suemnicht (December 1991) Oxygen Isotope Evidence For Past And Present Hydrothermal Regimes Of Long Valley Caldera, California