Publications
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Growth of the Tongariro volcanic complex: New evidence from K-Ar age determinations
New K-Ar age determinations indicate that the exposed portion of the Tongariro volcanic complex has grown steadily since at least 275 ka, with intervals of vigorous cone growth at 210-200.130-70. and 25 ka to the present day.
Authors
B.J. Hobden, Bruce F. Houghton, M. A. Lanphere, I.A. Nairn
Differentiation and magma mixing on Kilauea's east rift zone: A further look at the eruptions of 1955 and 1960. Part II. The 1960 lavas
New and detailed petrographic observations, mineral compositional data, and whole-rock vs glass compositional trends document magma mixing in lavas erupted from Kilauea's lower east rift zone in 1960. Evidence includes the occurrence of heterogeneous phenocryst assemblages, including resorbed and reversely zoned minerals in the lavas inferred to be hybrids. Calculations suggest that this mixing, w
Authors
T. L. Wright, Rosalind Tuthill Helz
Thermal conductivity of water-saturated rocks from the KTB pilot hole at temperatures of 25 to 300°C
The conductivitites of selected gneiss (two) and amphibolite (one) core samples have been measured under conditions of elevated temperature and pressure with a needle‐probe. Water‐saturated thermal conductivity measurements spanning temperatures from 25 to 300°C and hydrostatic pressures of 0.1 and 34 MPa confirm the general decrease in conductivity with increasing temperature but deviate signific
Authors
D. Pribnow, C.F. Williams, J. H. Sass, R. Keating
Chemical and isotopic characteristics of fluids along the cameroon volcanic line, cameroon
Results of the chemical and isotopic analysis of the water and gases discharged from volcanic crater lakes and soda springs located along the Cameroon Volcanic Line were used to characterize and infer their genetic relationships. Variations in the solute compositions of the waters indicate the dominant influence of silicate hydrolysis. Na+ (40-95%) constitutes the major cation in the springs while
Authors
G.Z. Tanyileke, M. Kusakabe, William C. Evans
Analysis of fractures intersecting Kahi Puka Well 1 and its relation to the growth of the island of Hawaii
As part of the Hawaii Scientific Drilling Project, Kahi Puka Well 1 penetrated about 275 m of Mauna Loa basalts overlying a sequence of Mauna Kea flow units as it was drilled and cored to a total depth of 1053 m below land surface. A borehole televiewer (BHTV) was run in most of the well in successive stages prior to casing in order to obtain magnetically oriented acoustic images of the borehole w
Authors
Roger H. Morin, Frederick L. Paillet
Kulshan caldera: A quaternary subglacial caldera in the North Cascades, Washington
Calderas that collapse during large pyroclastic eruptions are anomalously rare in the Cascade arc. Recognition of the early Pleistocene 4.5 × 8 km Kulshan caldera, filled with rhyodacite ignimbrite at the northeast foot of Mount Baker, brings to only three the Quaternary calderas identified in the Cascades. A near-vertical ring fault cut in basement rocks of the North Cascades encloses 30 km2 of i
Authors
W. Hildreth
Coral ages and island subsidence, Hilo drill hole
A 25.8-m-thick sedimentary section containing coral fragments occurs directly below a surface lava flow (the -1340 year old Panaewa lava flow) at the Hilo drill hole. Ten coral samples from this section dated by accelerator mass spectrometry. (AMS) radiocarbon and five by thermal infrared multispectral scanner (TIMS) 23øTh/U methods show good agreement. The calcareous unit is 9790 years old at the
Authors
J. G. Moore, B. L. Ingram, K. R. Ludwig, D. A. Clague
A catastrophic flood caused by drainage of a caldera lake at Aniakchak Volcano, Alaska, and implications for volcanic hazards assessment
Aniakchak caldera, located on the Alaska Peninsula of southwest Alaska, formerly contained a large lake (estimated volume 3.7 × 109 m3) that rapidly drained as a result of failure of the caldera rim sometime after ca. 3400 yr B.P. The peak discharge of the resulting flood was estimated using three methods: (1) flow-competence equations, (2) step-backwater modeling, and (3) a dam-break model. The r
Authors
C. F. Waythomas, J. S. Walder, R. G. McGimsey, C. A. Neal
Three-dimensional P and S wave velocity structure of Redoubt Volcano, Alaska
The three‐dimensional P and S wave structure of Redoubt Volcano, Alaska, and the underlying crust to depths of 7–8 km is determined from 6219 P wave and 4008 S wave first‐arrival times recorded by a 30‐station seismograph network deployed on and around the volcano. First‐arrival times are calculated using a finite‐difference technique, which allows for flexible parameterization of the slowness mod
Authors
H. M. Benz, B. A. Chouet, P.B. Dawson, J.C. Lahr, R.A. Page, J.A. Hole
Waters associated with an active basaltic volcano, Kilauea, Hawaii: Variation in solute sources, 1973-1991
Chemical and isotopic analyses of samples collected from a December 1962-m-deep research borehole at the summit of Kilauea Volcano provide unique time-series data for composition of waters in the uppermost part of its hydrothermal system. These waters have a distinctive geochemical signature: a very low proportion of chloride relative to other anions compared with other Hawaiian waters—thermal (•3
Authors
R. I. Tilling, B.F. Jones
A quantitative look at the demise of a basaltic vent: The death of Kupaianaha, Kilauea Volcano, Hawai'i
The Kupaianaha vent, the source of the 48th episode of the 1983-to-present Pu'u 'O'o-Kupaianaha eruption, erupted nearly continuously from July 1986 until February 1992. This investigation documents the geophysical and geologic monitoring of the final 10 months of activity at the Kupaianaha vent. Detailed very low frequency (VLF) electromagnetic profiles across the single lava tube transporting la
Authors
J. Kauahikaua, M. Mangan, C. Heliker, T. Mattox
Hydrogeology of the Hawaii Scientific Drilling Project borehole KP-1 1. Hydraulic conditions adjacent to the well bore
Temperature and formation resistivity logs obtained in borehole KP-1 of the Hawaii Scientific Drilling Project indicate that the adjacent formation is characterized by several zones of distinctly different average temperature and water salinity. A series of hydraulic analyses and water sampling programs were conducted to rule out the possibility of local hydraulic effects associated with the prese
Authors
Frederick L. Paillet, D. M. Thomas