Petrology of deep drill hole, Kilauea Volcano

Conference · Wed Dec 01 04:00:00 EST 1976 · EOS, Trans., Am. Geophys. Union; (United States)

OSTI ID:5321487

Grose, L T ^[1]; Keller, G V

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1. Colorado School of Mines, Golden

The first deep drill hole (1262 m TD) at the summit of an active volcano (1102 m elev) was drilled in 1973 at Kilauea volcano, Hawaii with support from NSF and USGS. The hole is located within southern margin of Kilauea caldera in northern part of a 15 km/sup 2/ triangular block bounded by east rift zone, Koae fault zone, and southwest rift zone-a summit area relatively free of faults, rifts, and extrusions. Nearest eruptions are from fissures 1.2 km away which are active in 1974 and which do not trend toward the drill hole. Core recovery totals 47 m from 29 core runs at rather evenly spaced intervals to total depth. Megascopic, thin-section, and X-ray examination reveals: (1) Recovered core is essentially vesicular, intergranular, nonporphyritic to porphyritic olivine basalt with minor olivine diabase, picrite diabase, and basalt, (2) Hyaloclastite and pillow basalt are absent, (3) Below water table (614 m elev) with increasing depth, vesicularity decreases, and density, crystallinity, competence, vesicle fill, and alteration irregularly increase, (4) Alteration first occurs at water table where calcite and silica partially fill vesticles and olivine is partially serpentinized, (5) At about 570 m elev massive serpentinization of olivine and deposition of montmorillonite-nontronite occur; at about 210 m elev truscottite and tobermorite occur in vesicles; at about 35 m elev mordenite occurs in vesicles, (6) Bottom-hole cores have complete filling of vesicles with silica, minor silica replacement, and complete alteration of olivine, and (7) Plagioclase is unaltered. Chemical analyses of bottom-hole cores are similar to those of modern summit lavas. Alteration and low porosity in bottom-hole cores plus abrupt temperature increase suggest the drill hole penetrated a self-sealed ''cap rock'' to a hydrothermal convection cell and possibly a magma body.

• OSTI ID: 5321487
• Conference Information: Journal Name: EOS, Trans., Am. Geophys. Union; (United States) Journal Volume: 57:12
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
150303* -- Geothermal Exploration & Exploration Technology-- Exploratory Drilling & Well Logging
ALKALINE EARTH METAL COMPOUNDS
BASALT
BOREHOLES
CALCITE
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CAP ROCK
CARBON COMPOUNDS
CARBONATES
CAVITIES
CHALCOGENIDES
DRILL CORES
GEOLOGIC STRUCTURES
GEOLOGY
GEOTHERMAL SYSTEMS
HAWAII
HYDROTHERMAL SYSTEMS
IGNEOUS ROCKS
KILAUEA VOLCANO
MAGMA SYSTEMS
MINERALS
NORTH AMERICA
OLIVINE
OXIDES
OXYGEN COMPOUNDS
PETROLOGY
RIFT ZONES
ROCKS
SILICA
SILICON COMPOUNDS
SILICON OXIDES
USA
VOLCANOES