Recovery of datable charcoal beneath young lavas: Lessons from Hawaii
J. P. Lockwood, P. W. Lipman
1980, Bulletin Volcanologique (43) 609-615
Field studies in Hawaii aimed at providing a radiocarbon-based chronology of prehistoric eruptive activity have led to a good understanding of the processes that govern the formation and preservation of charcoal beneath basaltic lava flows. Charcoal formation is a rate-dependent process controlled primarily by temperature and duration of heating, as...
Biogenic and thermogenic origins of natural gas in Cook Inlet basin, Alaska.
George E. Claypool, C. N. Threlkeld, L. B. Magoon
1980, American Association of Petroleum Geologists Bulletin (64) 1131-1139
Two types of natural gas occurrences are present in the Cook Inlet basin. The major reserves (1.8 × 1011m3) occur in shallow (less than 2,300 m), nonassociated dry gas fields that contain methane with ^dgr13C in the range of -63 to -56 per mil. These gas fields are in sandstones...
Arctic sea-ice variations from time-lapse passive microwave imagery
W. J. Campbell, R.O. Ramseier, H.J. Zwally, P. Gloersen
1980, Boundary-Layer Meteorology (18) 99-106
This paper presents: (1) a short historical review of the passive microwave research on sea ice which established the observational and theoretical base permitting the interpretation of the first passive microwave images of Earth obtained by the Nimbus-5 ESMR; (2) the construction of a time-lapse motion picture film of a...
Water resources of the People's Republic of China
N.C. Matalas, C.F. Nordin Jr.
1980, Eos, Transactions, American Geophysical Union (61) 891-901
At the invitation of the Society of Hydraulic Engineers of the People's Republic of China (PRC), a delegation of U.S. hydrologists and hydraulic engineers visited the PRC in the fall of 1978.* From discussions with officials of both the Society and the Ministry of Water Conservancy and Power (MWCP), and...
Debris-flow deposits of Early Miocene age, Deadman Stream, Marlborough, New Zealand.
D.W. Lewis, M.G. Laird, R.D. Powell
1980, Sedimentary Geology (27) 83-118
Detailed analysis is presented of a conformable succession of conglomerates and sandstones lying between massive marine mudstones. The coarse sediments reflect deposition by a spectrum of subaqueous debris-flow mechanisms during an early pulse of tectonism that ultimately resulted in Plio-Pleistocene eversion of the Kaikoura Mountains. Sparse pebbly mudstones and rare...
Late Wisconsin and Holocene tectonic stability of the United States mid-Atlantic coastal region
B. W. Blackwelder
1980, Geology (8) 534-537
Deposits that formed in the intertidal zone during sea-level rise 12,000 to 9,000 yr ago have undergone very little differential vertical deformation in the area between New York City and South Carolina. The lack of north-south vertical deformation contrasts with tide-gauge and with...
Quantile estimation with more or less floodlike distributions
J. Maciunas Landwehr, N.C. Matalas, J.R. Wallis
1980, Water Resources Research (16) 547-555
The desirable properties of an estimator relative to a hypothetical population may be irrelevant in practice unless the population at issue more or less resembles the hypothetical population. Evidence that floods are distributed with long, stretched upper tails suggests that use of the more common distributions results in a rather...
Radioactivity method
J. S. Duval
1980, Geophysics (45) 1690-1694
Radioactivity measurements have played an important role in geophysics since about 1935, and they have increased in importance to the present. The most important areas of application have been in petroleum and uranium exploration. Radioactivity measurements have proved useful in geologic mapping, as well as in specialized applications such as...
Petrology of Hualalai volcano, Hawaii: Implication for mantle composition
D.A. Clague, E.D. Jackson, T. L. Wright
1980, Bulletin Volcanologique (43) 641-656
Hualalai is one of five volcanoes whose eruptions built the island of Hawaii. The historic 1800-1801 flows and the analyzed prehistoric flows exposed at the surface are alkalic basalts except for a trachyte cone and flow at Puu Waawaa and a trachyte maar deposit near Waha Pele. The 1800-1801 eruption...
Ocean eddy structure by satellite radar altimetry required for iceberg towing
W. J. Campbell, R. E. Cheney, J. G. Marsh, N. M. Mognard
1980, Cold Regions Science and Technology (1) 211-221
Models for the towing of large tabular icebergs give towing speeds of 0.5 knots to 1.0 knots relative to the ambient near surface current. Recent oceanographic research indicates that the world oceans are not principally composed of large steady-state current systems, like the Gulf Stream, but that most of the...
Rate of mercury loss from contaminated estuarine sediments
Michael H. Bothner, R.A. Jahnke, M. L. Peterson, R. Carpenter
1980, Geochimica et Cosmochimica Acta (44) 273-285
The concentration of mercury in contaminated estuarine sediments of Bellingham Bay, Washington was found to decrease with a half-time of about 1.3 yr after the primary anthropogenic source of mercury was removed. In situ measurements of the mercury flux from sediments, in both dissolved and volatile forms, could not account...
Computational methods for inverse problems in geophysics: Inversion of travel time observations
V. Pereyra, H.B. Keller, W.H.K. Lee
1980, Physics of the Earth and Planetary Interiors (21) 120-125
General ways of solving various inverse problems are studied for given travel time observations between sources and receivers. These problems are separated into three components: (a) the representation of the unknown quantities appearing in the model; (b) the nonlinear least-squares problem; (c) the direct, two-point ray-tracing problem used to compute...
Gas and hydrogen isotopic analyses of volcanic eruption clouds in Guatemala sampled by aircraft
W.I. Rose Jr., R.D. Cadle, L.E. Heidt, I. Friedman, A.L. Lazrus, B.J. Huebert
1980, Journal of Volcanology and Geothermal Research (7) 1-10
Gas samples were collected by aircraft entering volcanic eruption clouds of three Guatemalan volcanoes. Gas chromatographic analyses show higher H2 and S gas contents in ash eruption clouds and lower H2 and S gases in vaporous gas plumes. H isotopic data demonstrate lighter isotopic distribution of water vapor in ash...
Secular, annual, and semiannual changes in the baseline level of the earth's magnetic field at North American locations
W.H. Campbell
1980, Journal of Geophysical Research Solid Earth (85) 6557-6571
Secular, annual, and semiannual changes were obtained from the midnight values of field on specially determined days of quiet magnetospheric conditions. From a selection of North American observatories the latitude variation of these changes was evaluated from 20° to 65°. Results for the active and quiet sun years (1958 and...
Treasures from the deep ( Metallic nodules).
D.Z. Piper
1980, Water Spectrum (13) 8-15
The composition, distribution, metric growth rates and variations in sea-floor metallic nodules are outlined and discussed The considerable age, slow accretion and relationship to underlying sediments are problems of origin which are yet to be solved and some speculative answers are discussed. Mining of the nodules is reviewed and its...
Fission-track age of the Mangaroa ash and tectonic implications at Wellington, New Zealand.
C. W. Naeser, S. Nishimura, Te Punga
1980, New Zealand Journal of Geology and Geophysics (23) 615-621
Three samples of zircon from the Mangaroa Ash, an important marker bed in the late Pleistocene deposits of the Wellington area, have been dated by fission-track analysis. The average age of the 3 zircon samples is 380 000 years. Since this tephra fell, vertical uplift at Tinakori Hill on the...
Lithospheric loading by the 1896 Riku-u earthquake, northern Japan: Implications for plate flexure and asthenospheric rheology
W. Thatcher, T. Matsuda, T. Kato, J. B. Rundle
1980, Journal of Geophysical Research Solid Earth (85) 6429-6435
Under favorable circumstances the time-dependent aseismic deformation resulting from the loading of the lithosphere by the stress drop of large dip slip earthquakes can be used to determine both the effective elastic plate thickness and the asthenospheric viscosity. The deformation has several similarities with the deflection of the lithosphere by...
Direct computation of the sensible heat flux
K. Watson
1980, Geophysical Research Letters (7) 616-618
An algorithm to determine the sensible heat flux from simple field measurements (wind speed, air and ground temperatures) has been developed. It provides a direct solution, in parametric form, which can be displayed graphically or tabularly. This method has an advantage over the previous iterative solution...
Shallow, low-permeability reservoirs of northern Great Plains: Assessment of their natural gas resources.
Dudley D. Rice, George W. Shurr
1980, American Association of Petroleum Geologists Bulletin (64) 969-987
Major resources of natural gas are entrapped in low-permeability, low-pressure reservoirs at depths less than 4,000 ft (1,200 m) in the northern Great Plains. This shallow gas is the product of the immature stage of hydrocarbon generation and is referred to as biogenic gas. Prospective low-permeability, gas-bearing reservoirs range in...
Some factors controlling the concentration of uranium in the world ocean
S. Bloch
1980, Geochimica et Cosmochimica Acta (44) 373-377
Low-temperature alteration of the oceanic crust is a major sink for the U supplied to the oceans and may account for about 50% of the estimated present-day input of this element. Uranium uptake by organic-rich sediments and coexisting phosphorites on continental margins is also important and may remove in excess...
Scaling variables and interpretation of eigenvalues in principal component analysis of geologic data
A.T. Miesch
1980, Journal of the International Association for Mathematical Geology (12) 523-538
The dominant feature distinguishing one method of principal components analysis from another is the manner in which the original data are transformed prior to the other computations. The only other distinguishing feature of any importance is whether the eigenvectors of the inner product-moment of the transformed data matrix are taken...
Use of altered volcanic ash falls in stratigraphic studies of coal-bearing sequences: an example from the Upper Cretaceous Ferron Sandstone Member of the Mancos Shale in central Utah.
Thomas A. Ryer, R.E. Phillips, B.F. Bohor, R. M. Pollastro
1980, Geological Society of America Bulletin (91) 579-586
The Ferron consists of 5 delta cycles, each of which includes one coal zone which contains at least one, and usually several, laterally persistent kaolinitic claystone partings. Laboratory study of the partings demonstrates that they represent altered volcanic ash falls. These partings have proven particularly useful in reconstructing the depositional...
Multiple ice flow directions during the Fraser Glaciation in the lower Skagit River drainage, northern Cascade Range, Washington
Paul L. Heller
1980, Arctic and Alpine Research (12) 299-308
Stratigraphic mapping and pebble-count data suggest that ice flowed in three different directions in the lower Skagit drainage of the northern Cascade Range during the Fraser Glaciation (∼ 10K to 20K BP). Glacier reconstructions suggest that till exposed at one site in the lower Skagit Valley was deposited by a...
Geochemical exploration for uranium in playas
D. L. Leach, K.P. Puchlik, R.K. Glanzman
1980, Journal of Geochemical Exploration (13) 251-283
Playas and closed-basin lakes represent unique geochemical environments for the entrapment and concentration of mobile chemical elements. For this reason, playas may be considered as potentially favorable areas for the accumulation of uranium. We investigated playa sediments to determine their value as possible sample media for determining the presence...
Goat paddock cryptoexplosion crater, Western Australia
J.E. Harms, D.J. Milton, J. Ferguson, D.J. Gilbert, W.K. Harris, B. Goleby
1980, Nature (286) 704-706
Goat Paddock, a crater slightly over 5 km in diameter (18??20??? S, 126??40???E), lies at the north edge of the King Leopold Range/Mueller Range junction in the Kimberley district, Western Australia (Fig. 1). It was noted as a geological anomaly in 1964 during regional mapping by the Bureau of Mineral...
