Tertiary climates and floristic relationships at high latitudes in the northern hemisphere
J. A. Wolfe
1980, Palaeogeography, Palaeoclimatology, Palaeoecology (30) 313-323
During the Paleocene and Eocene, climates were characterized by a low mean annual range of temperature (a maximum of 10-15??C), a moderate to high mean annual temperature (10-20??C), and abundant precipitation; strong broad-leaved evergreen vegetation extended to almost lat. 60??N during the Paleocene and to well above 61??N during the...
Leg 67: the Deep Sea Drilling Project Mid-America Trench transect off Guatemala.
Roland E. von Huene
1980, Geological Society of America Bulletin (91) 421-432
Drilling on the Cocos plate recovered a basal chalk sequence deposited during early and mid-Miocene time, a short interval of abyssal red clay, and an upper sequence of late Miocene and younger sediment deposited within an area influenced by a terrigenous source. In the trench, a mud and sand fill...
Evaluation of multispectral middle infrared aircraft images for lithologic mapping in the East Tintic Mountains, Utah
A.B. Kahle, L. C. Rowan
1980, Geology (8) 234-239
Six channels of multispectral middle infrared (8 to 14 μrn) aircraft scanner data were acquired over the East Tintic mining district, Utah. This area has high relief and moderate vegetation and consists mainly of Tertiary silicic igneous rocks and Paleozoic quartzite and carbonate...
Geology and biology of Oceanographer submarine canyon.
P. C. Valentine, J. R. Uzmann, R.A. Cooper
1980, Marine Geology (38) 283-312
Santonian beds more than 100 m thick are the oldest rocks collected from the canyon. Quaternary silty clay veneers the canyon walls in many places and is commonly burrowed by benthic organisms that cause extensive erosion of the canyon walls, especially in the depth zone (100-1300 m) inhabited by the...
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...
Impact of horse traffic on trails in Rocky Mountain National Park.
R.M. Summer
1980, Journal of Soil and Water Conservation (35) 85-87
Disturbances related to the impact of horses on trails in Rocky Mountain National Park vary across the landscape. Geomorphic monitoring of permanent sites suggests that horse traffic is not the single, dominant process active on trails, nor is degredation always a direct result of horse use. Instead, amounts and rates...
Degradation of the Hebgen Lake fault scarps of 1959
R.W. Wallace
1980, Geology (8) 225-229
Scarps produced during the Hebgen Lake earthquake of 1959 changed noticeably in 19 yr although they still appeared remarkably fresh in 1978. They have degraded much more rapidly than have those produced in 1915 and 1954 in Nevada, but a quasi-stable slope of...
A comparison of artifical and natural slope failures: the Santa Barbara earthquake of August 13, 1978.
E. L. Harp, D. K. Keefer, R. C. Wilson
1980, California Geology (33) 102-105
The earthquake triggered rockfalls and rockslides from steep road cuts and coastal cliffs. The landslide reconnaissance survey which was carried out is described, with separate comments on each landslide site recorded. The general regional slope response to the earthquake is briefly considered. -R. House...
Elastic moduli of rock glasses under pressure to 8 kilobars and geophysical implications
R. Meister, E.C. Robertson, R.W. Werke, R. Raspet
1980, Journal of Geophysical Research Solid Earth (85) 6461-6470
Shear and longitudinal velocities were measured by the ultrasonic phase comparison method as a function of pressure to 8 kbar on synthetic glasses of basalt, andesite, rhyolite, and quartz composition and on natural obsidian. Velocities of most of the glasses decrease anomalously with pressure, but increasingly more-normal behavior occurs with...
Chemical mass-wasting of the northern Yucatan Peninsula by groundwater dissolution
B.B. Hanshaw, W. Back
1980, Geology (8) 222-224
The northern part of the Yucatan Peninsula is a relatively flat, low-lying carbonate terrane with no geomorphic expressions of stream channels. It is estimated that mean annual recharge to the groundwater system is 150 mm. For the 65,500 km2 study area, mean annual discharge (equivalent to recharge) is 9.8 × 109 m3,...
Geologic history of Grecian Rocks, Key Largo Coral Reef Marine Sanctuary.
E.A. Shinn
1980, Bulletin of Marine Science (30) 646-656
Two transects were drilled across the major ecologic zones of the c. 750 by 200 m reef, whose accumulation was controlled by a local Pleistocene topographic feature. The Reef is composed of 5 major ecologic zones: 1) a deep seaward rubble zone, 6-8 m depth; 2) a poorly developed spur...
Geophysical observations of Kilauea Volcano, Hawaii, 2. Constraints on the magma supply during November 1975-September 1977
D. Dzurisin, L. A. Anderson, G. P. Eaton, R. Y. Koyanagi, P. W. Lipman, J. P. Lockwood, R.T. Okamura, G. S. Puniwai, M. K. Sako, K.M. Yamashita
1980, Journal of Volcanology and Geothermal Research (7) 241-269
Following a 22-month hiatus in eruptive activity, Kilauea volcano extruded roughly 35 ?? 106 m3 of tholeiitic basalt from vents along its middle east rift zone during 13 September-1 October, 1977. The lengthy prelude to this eruption began with a magnitude 7.2 earthquake on 29 November, 1975, and included rapid...
Modern and ancient submarine fans: Discussion of papers by Walker and Normark.
Tor H. Nilsen
1980, American Association of Petroleum Geologists Bulletin (64) 1094-1101
No abstract available....
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...
The role of volatiles and lithology in the impact cratering process.
Kieffer S. Werner, C.H. Simonds
1980, Reviews of Geophysics and Space Physics (18) 143-181
A survey of published descriptions of 32 of the largest, least eroded terrestrial impact structures reveals that the amount of melt at craters in crystalline rocks is approximately 2 orders of magnitude greater than at craters in sedimentary rocks. In this paper we present a model for the impact process;...
(π−1) → (π−1), (π−1) emission spectra of chlorofluorobenzene cations in the gaseous phase and their lifetimes in the (0o) states
John Paul Maier, O. Marthaler, Manijeh Mohraz, R.H. Shiley
1980, Chemical Physics (47) 295-305
The radiative decay of seventeen electronically excited chlorofluorobenzene cations in the gaseous phase has been detected. The reported emission spectra, which have been obtained using low energy electron beam excitation, are assigned to the B(??-1 ??? X(??-1 electronic transitions of these cations on the basis of their Ne(I) photoelectron spectra....
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...
Electrochemistry and the geochemist
H. A. Tourtelot
1980, Nature (288) 218
No abstract available. ...
The distribution and mobility of uranium in glassy and zeolitized tuff, Keg Mountain area, Utah, U.S.A.
R. A. Zielinski, D. A. Lindsey, J.N. Rosholt
1980, Chemical Geology (29) 139-162
The distribution and mobility of uranium in a diagenetically altered, 8 Ma old tuff in the Keg Mountain area, Utah, are modelled in this study. The modelling represents an improvement over similar earlier studies in that it: (1) considers a large number of samples (76) collected with good geologic control...
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...
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...
Emission spectra of the cations of 1,3- and 1,4-dibromotetrafluorobenzene and of 1,3,5-tribromotrifluorobenzene in the gaseous phase
John Paul Maier, O. Marthaler, Manijeh Mohraz, R.H. Shiley
1980, Chemical Physics (47) 307-312
A search was made for radiative decay of electronically excited cations of 24 bromobenzenes and of their fluoro-substituted derivatives in the gaseous phase. The only emission spectra detected were for the cations of 1,3- and 1,4-dibromotetrafluorobenzene and of 1,3,5-tribromotrifluorobenzene. The band systems, which are found between 670 and 830 nm,...
The mass balance approach: application to interpreting the chemical evolution of hydrologic systems
Niel Plummer, W. Back
1980, American Journal of Science (280) 130-142
Mass balance calculations are applied to observed chemical and isotopic data of three natural water systems involving carbonate reactions in order to define mineral stoichiometry of reactants and products, relative rates of reactions, and mass transfer. One study evaluates reactions in a lagoon on the east coast of the Yucatan...
Hydrogen sulfide removal with boric acid
M. M. Schnepfe
1980, Analytical Chemistry (52) 1534-1535
No abstract available....
Sr isotopic fractionation in Ca-Al inclusions from the Allende meteorite
P. J. Patchett
1980, Nature (283) 438-441
True relative Sr isotopic compositions, determined by double spiking on Ca-Al inclusions from the Allende meteorite show up to 1.5??? per mass unit mass fractionation relative to the Earth and bulk chondrites. All abnormal inclusions are light-isotope enriched. A lack of isotopically heavy Sr in inclusions would place constraints on...