# Geology

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Willem A. Landman

S. R. Taylor, S.M. McLennan

Parameters on which models for terrestrial lead isotope evolution are based have recently been revised. These parameters are the isotopic composition of troilite lead, the age of the meteorite system and the decay constants of uranium and thorium. As...

A large data set consisting of about 1000 normal mode periods, 500 summary travel time observations, 100 normal mode Q values, mass and moment of inertia have been inverted to obtain the radial distribution of elastic properties, Q values and density...

Bernard P. Tissot, Dietrich H. Welte

Compositional models of the Earth are critically dependent on three main sources of information: the seismic profile of the Earth and its interpretation, comparisons between primitive meteorites and the solar nebula composition, and chemical and petrological...

The range of As concentrations found in natural waters is large, ranging from less than 0.5 μg l−1 to more than 5000 μg l−1. Typical concentrations in freshwater are less than 10 μg l−1 and frequently less than 1 μg l−1. Rarely,...

J. K. Mitchell

Granites may be subdivided according to their intrusive settings into four main groups—ocean ridge granites (ORG), volcanic arc granites (VAG), within plate granites (WPG) and collision granites (COLG)—and the granites within each group may be further...

Recently reported radioisotopic dates and magnetic anomaly spacings have made it evident that modification is required for the age calibrations for the geomagnetic polarity timescale of Cande and Kent (1992) at the Cretaceous/Paleogene boundary and in...

Robert L. Folk

The focus of this paper is the conversion of radiocarbon ages to calibrated (cal) ages for the interval 24,000-0 cal BP (Before Present, 0 cal BP = AD 1950), based upon a sample set of dendrochronologically dated tree...

A system is presented whereby volcanic rocks may be classified chemically as follows:I. Subalkaline Rocks:A. Tholeiitic basalt series:Tholeiitic picrite-basalt; tholeiite; tholeiitic andesite.B. Calc-alkali series:High-alumina basalt; andesite; dacite;...

The focus of this paper is the conversion of radiocarbon ages to calibrated (cal) ages for the interval 24,000-0 cal BP (Before Present, 0 cal BP = AD 1950), based upon a sample set of dendrochronologically dated tree...

The thermodynamic properties of 154 mineral end-members, 13 silicate liquid end-members and 22 aqueous fluid species are presented in a revised and updated data set. The use of a temperature-dependent thermal expansion and bulk modulus, and the use of...

Bryozoan reef mounds are common features in the geological record, occurring within mid-ramp, slope paleoenvironments, especially in Paleozoic carbonate successions, but until now have not been recorded from the modern ocean. Recent scientific drilling...

Robert L. Folk

The climatically sensitive zone of the Arctic Ocean lies squarely within the domain of the North Atlantic oscillation (NAO), one of the most robust recurrent modes of atmospheric behavior. However, the specific response of the Arctic to annual and longer-period...

J. Casey Moore, John B. Diebold, M. A. Fisher, Sample Jh, Thomas M. Brocher, R. von Huene, C. Rowe, D. Stone, Chris Stevens, Dale S. Sawyer

This paper reviews the necessary considerations and available techniques for assessing the accuracy of remotely sensed data. Included in this review are the classification system, the sampling scheme, the sample size, spatial autocorrelation, and the...

A simple model for the development and evolution of sedimentary basins is proposed. The first event consists of a rapid stretching of continental lithosphere, which produces thinning and passive upwelling of hot asthenosphere. This stage is associated...

At Elan Bank of the Kerguelen Plateau in the southeast Indian Ocean, Leg 183 of the Ocean Drilling Program recovered clasts of garnet-biotite gneiss in a fluvial conglomerate intercalated with basalt flows. U-Pb and Pb-Pb dates of zircons and monazites...

Standards for reporting C-14 age determinations are discussed. All dates should be related either directly or indirectly to the NBS oxalic acid standard. Corrections for isotopic fractionation are also desirable. For some materials, particularly marine...

Traveltimedatafromthe1993SouthernSierraNevadaContinentalDynamicsseismic refractionexperimentreveallowcrustalvelocitiesinthesouthernSierraNevadaandBasin and Range province of California (6.0 to 6.6 km/s), as well as low upper mantle velocities...

M. J. Le Bas, R. W. Le Maitre, Albert Streckeisen, B. Zanettin

An expanded Oligocene-Miocene boundary interval recovered in the Cape Roberts Project CRP-2A core from beneath the Ross Sea, Antarctica, has yielded a high-resolution integrated chronostratigraphy that has, in turn, enabled a new, more direct, calibration...

Simone Fatichi, V. Y. Ivanov, Enrica Caporali

A new calculation of the crustal composition is based on the proportions of upper crust (UC) to felsic lower crust (FLC) to mafic lower crust (MLC) of about 1:0.6:0.4. These proportions are derived from a 3000 km long...

Since the publication of our previous time scale (Berggren and others, 1985c = BKFV85) a large amount of new magneto- and biostratigraphic data and radioisotopic ages have become available. An evaluation of some of the key magnetobiostratigraphic calibration...

Author Posting. © Arizona Board of Regents on behalf of the University of Arizona, 2004. This article is posted here by permission of Dept. of Geosciences, University of Arizona for personal use, not for redistribution. The definitive version was published...

Summary. The classic, multivariate technique of principal component analysis can be used to find and estimate the directions of lines and planes of best least-squares fit along the demagnetization path of a palaeomagnetic specimen, thereby replacing vector...

A high-resolution multiparameter stratigraphy allows the identification of late Quaternary glacial and interglacial cycles in a central Arctic Ocean sediment core. Distinct sandy layers in the upper part of the otherwise fine-grained sediment core from...

D. G. Fredlund, H. Rahardjo

The IntCal09 and Marine09 radiocarbon calibration curves have been revised utilizing newly available and updated data sets from 14 C measurements on tree rings, plant macrofossils, speleothems, corals, and foraminifera. The calibration curves were derived...

Charles DeMets, Richard G. Gordon, Donald F. Argus, Seth Stein

G. C. Topp, J. L. Davis, A. P. Annan

A weekly 1° spatial resolution optimum interpolation (OI) sea surface temperature (SST) analysis has been produced at the National Oceanic and Atmospheric Administration (NOAA) using both in situ and satellite data from November 1981 to the present....

J. Smit, Th.B. Roep, W.J. Alvarez, Ph. Claeys, A. Montanari, Wolfgang Stinnesbeck, Gerta Keller, Thierry Adatte, N. MacLeod, Christian Koeberl, R. Rocchia, John Lyons, Charles B. Officer

This paper presents a table of abundances of the elements in the various major units of the Earth's lithic crust with a documentation of the sources and a discussion of the choice of units and data.

Experimental results in the published literature show that at low normal stress the shear stress required to slide one rock over another varies widely between experiments. This is because at low stress rock friction is strongly dependent on surface roughness....

Tectonic stress and the spectra of seismic shear waves from earthquakes

A bar on the Brazos River near Calvert, Texas, has been analyzed in order to determine the geologic meaning of certain grain size parameters and to study the behavior of the size fractions with transport. The bar consists of a strongly bimodal mixture...

Two models, a simple cooling model and the plate model, have been advanced to account for the variation in depth and heat flow with increasing age of the ocean floor. The simple cooling model predicts a linear relation between depth and t , and heat...

Henry Faul

The new NOAA operational global sea surface temperature (SST) analysis is described. The analyses use 7 days of in situ (ship and buoy) and satellite SST. These analyses are produced weekly and daily using optimum interpolation (OI) on a 1° grid. The...

Robert S. White, Dan McKenzie

Using the concept of “orbital tuning,” a continuous, high-resolution deep-sea chronostratigraphy has been developed spanning the last 300,000 yr. The chronology is developed using a stacked oxygen-isotope stratigraphy and four different orbital tuning...

Analyses for Ti, Zr, Y, Nb and Sr in over 200 basaltic rocks from different tectonic settings have been used to construct diagrams in which these settings can usually be identified. Basalts erupted within plates (ocean island and continental basalts)...

Galeras volcano reactivated in early 1988, as evidenced by increased seismicity, gas emissions, and fumarole temperatures, and had a series of explosive eruptions in May 1989. During 1989-1990 the volcano was characterized by high SO2 flux, reaching 5000...

The average chemical compositions of the continental crust and the oceanic crust (represented by MORB), normalized to primitive mantle values and plotted as functions of the apparent bulk partition coefficient of each element, form surprisingly simple,...

A number of marine water and fresh water samples were examined for the relative ratio, and the variation of this ratio was determined to a precision of ± 0.1%. In the case of surface marine waters, for a range of salinity of 29.40%.,...

The composition of the stream system of a drainage basin can be expressed quantitatively in terms of stream order, drainage density, bifurcation ratio, and stream-length ratio.Stream orders are so chosen that the fingertip or unbranched tributaries are...

The radiative and physiological effects of doubled atmospheric carbon dioxide (CO2) on climate are investigated using a coupled biosphere‐atmosphere model. Five 30-yr climate simulations, designed to assess the radiative and physiological effects of...

Gridded fields (analyses) of global monthly precipitation have been constructed on a 2.5° latitude–longitude grid for the 17-yr period from 1979 to 1995 by merging several kinds of information sources with different characteristics, including gauge...

Philip N. Froelich, Gary P. Klinkhammer, Michael L. Bender, Nile A. Luedtke, G.R. Heath, Cullen Dr, Paul Dauphin, D. P. Hammond, B. J. Hartman, Val Maynard

The geodynamic evolution of the western part of the Sunda arc is controlled by the change from frontal subduction of the Indo-Australian plate along Java to oblique subduction along Sumatra. This obliquity gives rise to the Sumatra fault zone that links...

The leading empirical orthogonal function of the wintertime sea-level pressure field is more strongly coupled to surface air temperature fluctuations over the Eurasian continent than the North Atlantic Oscillation (NAO). It resembles the NAO in many respects;...

Roberta L. Rudnick, Shan Gao

J. G. Liou, Stephan A. Graham, S. Maruyama, X. Wang, X. Xiao, Alan R. Carroll, J. Chu, Y. Feng, M.S. Hendrix, Y.H. Liang, C.L. McKnight, Y. Tang, Z.X. Wang, Min Zhao, B. Zhu

J. G. Arnold, R. Srinivasan, Ranjan S. Muttiah, Jimmy R. Williams

Lorraine E. Lisiecki, Maureen E. Raymo

Charles DeMets, Richard G. Gordon, Seth Stein

The primary purpose of this study is to assess the performance of 1D solar radiative transfer codes that are used currently both for research and in weather and climate models. Emphasis is on interpretation and handling of unresolved clouds. Answers are...

New values for the astronomical parameters of the Earth's orbit and rotation (eccentricity, obliquity and precession) are proposed for paleoclimatic research related to the Late Miocene, the Pliocene and the Quaternary. They have been obtained from a...

The tracer-diffusion coefficient of ions in water, Dj0, and in sea water, , differ by no more than zero to 8 per cent. When sea water diffuses into a dilute solution of water, in order to maintain the electro-neutrality, the average diffusion coefficients...

New data and new estimates from old data show that rivers with large sediment loads (annual discharges greater than about $15 \times 10^{6}$ tons) contribute about $7 \times 10^{9}$ tons of suspended sediment to the ocean yearly. Extrapolating available...

Five test runs were performed to assess possible bias when performing the loss on ignition (LOI) method to estimate organic matter and carbonate content of lake sediments. An accurate and stable weight loss was achieved after 2 h of burning pure CaCO3...

The Guffey volcanic center is the largest within the 2000 km2 mid-Tertiary Thirtynine Mile volcanic field of central Colorado. This study is the first to provide extensive chemical data for these alkalic volcanic and subvolcanic rocks, which represent...

A.M.Celâl ^̧Sengör, Yücel Yilmaz

J. Bernard Minster

Rasmus C. Thiede, Todd A. Ehlers, Bodo Bookhagen, Manfred R. Strecker

Empirical relations involving seismic moment Mo, magnitude Ms, energy Es and fault dimension L (or area S) are discussed on the basis of an extensive set of earthquake data (M s >= 6) and simple crack and dynamic dislocation models. The relation between...

Soil taxonomy—a basic system of soil classification for making and interpreting soil surveys

John M. Hunt

Joseph B. Whalen, Kenneth L. Currie, Bruce W. Chappell

The nearly coincident forms of the relations between seismic moment M_0 and the magnitudes M_L, M_S, and M_w imply a moment magnitude scale M = ⅔ log M_0 - 10.7 which is uniformly valid for 3 ≲ M_L ≲ 7, 5 ≲ M_s ≲ 7½, and M_w ≳ 7½.

The overall mechanics of fold-and-thrust belts and accretionary wedges along compressive plate boundaries is considered to be analogous to that of a wedge of soil or snow in front of a moving bulldozer. The material within the wedge deforms until a critical...

Volcanic are basalts can usually be distinguished from basalts erupted in other settings by their selective enrichments in LIL elements and also, in some cases, in light rare-earth elements and P. Ibis enrichment component is independent of the nature...

Summary Examination of more than 100 fault plane solutions for earthquakes within the Alpide belt between the Mid-Atlantic ridge and Eastern Iran shows that the deformation at present occurring is the result of small continental plates moving away from...

David J. Prior, Natasha Grant, G. E. Lloyd, Alastair Welbon, K. H. Brodie, R. H. Maddock, S. H. White, T. H. Bell, Colin C. Ferguson, John Wheeler

Core Vema 28-238 preserves an excellent oxygen isotope and magnetic stratigraphy and is shown to contain undisturbed sediments deposited continuously through the past 870,000 yr. Detailed correlation with sequences described by Emiliani in the Caribbean...

A revised regular solution-type thermodyn- amic model for twelve-component silicate liquids in the system SiOa-TiO2 A1203-Fe203-Cr203-FeO MgO CaO-Na20-K20 P2Os-H20 is calibrated. The model is referenced to previously published standard state thermodynamic...

The introduction of a fifth amphibole group, the Na-Ca-Mg-Fe-Mn-Li group, defined by 0.50 < B(Mg, Fe2+, Mn2+, Li) < 1.50 and 0.50 < = B(Ca, Na) < = 1.50 apfu (atoms per formula unit), with members whittakerite and ottoliniite,...

This paper addresses and documents a number of issues related to the implementation of an advanced land surface‐hydrology model in the Penn State‐NCAR fifth-generation Mesoscale Model (MM5). The concept adopted here is that the land surface model...

A review of the geologic history of the Himalayan-Tibetan orogen suggests that at least 1400 km of north-south shortening has been absorbed by the orogen since the onset of the Indo-Asian collision at about 70 Ma. Significant crustal shortening, which...

A large body of information on emissions from the various types of biomass burning has been accumulated over the past decade, to a large extent as a result of International Geosphere-Biosphere Programme/International Global Atmospheric Chemistry research...

This paper reports new developments in in situ U–Pb zircon geochronology using 266 and 213 nm laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS).

The most frequently used climate classification map is that o f Wladimir Koppen, presented in its latest version 1961 by Rudolf Geiger. A huge number of climate studies and subsequent publications adopted this or a former release of the Koppen-Geiger...

Volcanic are basalts are all characterized by a selective enrichment in incompatible elements of low ionic potential, a feature thought to be due to the input of aqueous fluids from subducted oceanic crust into their mantle source regions. Island arc...

A marine seismic reflection line across the northeast extremity of the Canadian Appalachians in Newfoundland indicates a collisional suture(?) in the lower crust beneath the central ophiolitic Dunnage terrane. The thrust and fold belt (miogeocline) above...

Alfred C. Redfield

A subgrid-scale form for mesoscale eddy mixing on isopycnal surfaces is proposed for use in non-eddy-resolving ocean circulation models. The mixing is applied in isopycnal coordinates to isopycnal layer thickness, or inverse density gradient, as well...

The Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA) provides a calibration-based sequential scheme for combining precipitation estimates from multiple satellites, as well as gauge analyses where feasible, at fine...

Data from experimental runs, coexisting phases in ultramafic rocks and phenocryst-matrix pairs in volcanic rocks have been used to compile a table of mineral-liquid distribution coefficients for Ti, Zr, Y, and Nb for basic, intermediate and acid melt...

The presence of common lead contamination in zircons used for U–Pb geochronology is a potentially serious source of error. Traditionally, common lead is measured by analysis of 204 Pb, and the isotopic composition of lead corrected accordingly. Some...

The rare earth pattern in sedimentary rocks is nearly constant and is considered to represent the relative abundances of these elements in the continental crust. This pattern is derived principally from mixing of basic and acidic igneous rock patterns....

Throughout Earth history, almost all preserved organic matter has been incorporated in marine sediments deposited under oxygenated waters along continental margins. Given modern oceanic productivity and sediment burial rates of 50 × 1015 and 0.16...

Analysis of data from 280 rivers discharging to the ocean indicates that sediment loads/yields are a log-linear function of basin area and maximum elevation of the river basin. Other factors controlling sediment discharge (e.g., climate, runoff) appear...

A number of in situ cosmogenic radionuclides and stable nuclides have been measured in natural exposed rock surfaces with a view to study their in situ production and rock erosion rates [1]. The in situ radionuclides can be used for a high-resolution...

The paper comments on the recommendations on which the IUGS Subcommission on the Systematics of Igneous Rocks agreed at Montreal, August 1972.Plutonic rocks are classified and named according to mineral contents. For nomenclature are considered: Q = quartz,...

Drilling near the deformation front of the northern Barbados Ridge cored an accretionary prism consisting of imbricately thrusted Neogene hemipelagic sediments detached from little-deformed Oligocene to Campanian underthrust deposits by a decollement...

Dan McKenzie, M. J. Bickle

A. M. Dziewonski, T.‐A. Chou, J.H. Woodhouse

The leading modes of variability of the extratropical circulation in both hemispheres are characterized by deep, zonally symmetric or ‘‘annular’’ structures, with geopotential height perturbations of opposing signs in the polar cap region and...

Logs collected while drilling measured density in situ, through the accretionary prism and decollement zone of the northern Barbados Ridge. Consolidation tests relate void ratio (derived from density) to effective stress and predict a fluid pressure profile,...

Observations of sea surface and land–near-surface merged temperature anomalies are used to monitor climate variations and to evaluate climate simulations; therefore, it is important to make analyses of these data as accurate as possible. Analysis uncertainty...

H. J. Melosh

P. Domenico, Franklin W. Schwartz

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