History and results of VC-1, the first CSDP corehole in Valles caldera, New Mexico
Valles Caldera No. 1 (VC-1) is the first Continental Scientific Drilling Program (CSDP) corehole drilled in the Valles caldera and the first continuously cored hole in the caldera region. The objectives of VC-1 were to penetrate a hydrothermal outflow plume near its source, to obtain structural and stratigraphic information near the intersection of the ring-fracture zone and the pre-caldera Jemez fault zone, and to core the youngest volcanic unit inside the caldera (Banco Bonito obsidian, 0.13 Ma). VC-1 penetrates 298 m of moat volcanics and caldera-fill ignimbrites, 35 m of pre-caldera volcaniclastic breccia, and 523 m of Paleozoic carbonates, sandstones and shales, with over 95% core recovery. Hydrothermal alterations are concentrated in sheared, brecciated and fractured zones from the volcaniclastic breccia to total depth with both the intensity and rank of alterations increasing with depth. Alterations consist primarily of clays, calcite, pyrite, quartz, and chlorite, but chalcopyrite has been identified as high as 518 m and molybdenite has been identified in a fractured zone at 847 m. Thermal aquifers were penetrated at various intervals from about 510 m on down. 11 refs., 5 figs.
- Research Organization:
- Los Alamos National Lab., NM (USA); Tonto Drilling Services, Inc., Salt Lake City, UT (USA); NL Baroid, Inc., Sandia Park, NM (USA)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 5573384
- Report Number(s):
- LA-UR-85-1005; CONF-850801-31; ON: DE85009640
- Resource Relation:
- Conference: International symposium on geothermal energy, Kailua Kona, HI, USA, 26 Aug 1985; Other Information: Portions of this document are illegible in microfiche products
- Country of Publication:
- United States
- Language:
- English
Similar Records
First CSDP (Continental Scientific Drilling Program)/thermal regimes core hole project at Valles Caldera, New Mexico (VC-1): Drilling report
Core lithology, Valles caldera No. 1, New Mexico
Related Subjects
BACA GEOTHERMAL FIELD
STRATIGRAPHY
CALDERAS
WELL DRILLING
DRILL CORES
PETROLOGY
AQUIFERS
BOREHOLES
HYDROTHERMAL ALTERATION
NEW MEXICO
CAVITIES
DRILLING
FEDERAL REGION VI
GEOLOGY
GEOTHERMAL FIELDS
NORTH AMERICA
USA
Geothermal Legacy
150201* - Geology & Hydrology of Geothermal Systems- USA- (-1989)