Showing papers in "Earth and Planetary Science Letters in 1988"

TL;DR: In this paper, 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, complementary concentration patterns.

TL;DR: In this article, the average Sm-Nd and Rb-Sr isotope parameters for the upper continental crust today are refined using a model of the North American continental surface.

TL;DR: In this paper, the authors present a data set of over 300 oceanic basalts from 43 oceanic islands or island groups, including the DUPAL belt, and show that 95% of all basalts with a strong DUPAL signature lie between 0° and 50° south latitude.

TL;DR: In this paper, an iterative procedure is used to determine the positions of variable-direction unit vectors so that the length,R, of the vector resultant of all (M + N) unit vectors is a maximum.

TL;DR: In this article, the authors measured the input to the oceans of rare earth elements (REE) in the dissolved and the suspended loads of rivers, and found that the dissolved loads in the five major rivers had relatively heavy-REE enrichments relative to the NASC and the suspension material, with the (La/Yb)N ratio of about 0.4.

TL;DR: In this paper, the authors show that the extent of melting in the mantle can easily account for the associated variations in Ca6.0 and Na6. 0 in the parent magmas.

TL;DR: In this article, infrared spectroscopy was used to determine dissolved H 2O and CO 2 contents in basaltic glasses from the Juan de Fuca Ridge and neighboring seamounts.

TL;DR: The authors proposed that the MORB21Ne/22Ne anomalies are due to nuclear reactions within the mantle, which is consistent with previous He-Ne-Ar-Xe data and their interpretation as representative of a deep undegassed mantle source.

TL;DR: Combined tritium/3He data from three multi-level sampling wells (DFG 1, DFG 4, and DFG 7) located at Liedern/ Bocholt, West Germany, are presented and principles of the tritiogenic3He method in shallow groundwater studies are discussed in this article.

TL;DR: In this article, a steady-state flux of He through the continents that may be estimated from He accumulations in lakes and aquifers is calculated from their 3He content.

TL;DR: In this article, the authors determined the concentrations and isotopic composition of noble gases in old oceanic crust and oceanic sediments and the isotopic compositions of noble gas in emanations from subduction volcanoes and concluded that at least 98% of the noble gases and water in the subducted slab returns back into the atmosphere through subduction volcano.

TL;DR: In the Kalgoorlie-norseman area of Australia, the first stage involved the formation of primitive crust, probably above subduction zones, and the second stage resulted from a major change in mantle convection that produced thermal upwellings in the mantle below the continents as mentioned in this paper.

TL;DR: In this article, the authors demonstrate the capacity of perovskites to accept a wide range of normally “incompatible” elements possessing diverse ionic radii and charges into their crystal structures.

TL;DR: In this paper, the first measurements of CO 2 solubility in molten basalt at pressures comparable to those at which submarine basalts erupt were reported, and the results were compatible with those obtained previously at higher pressures on a molten Kilauea tholeiite.

TL;DR: In this article, Nd and Sm concentrations and Nd isotopic compositions were measured on the detrital fraction of deep-sea surface sediments and on aerosols sampled over the North Atlantic and Mediterranean Sea.

TL;DR: The relationship between reduced track density, ϱ/ϱ 0, and reduced mean confined track length, L/L 0, during annealing has been studied for both spontaneous and induced tracks in four apatite samples with different chemical composition, compositional range, and origin this paper.

TL;DR: In this article, the most southern basalts in the Deccan Trap, India were studied and three chemical formations were recognized, two of which can be correlated with the established stratigraphy in Mahabaleshwar and imply a regional southerly dip of 0.06° over a distance of 250 km.

TL;DR: In the absence of fluids, the enrichment pattern isRa⋍Th>U, and in a “wet” environment Ra > U > Th as mentioned in this paper.

TL;DR: In this article, the authors show that the cross-sectional shape of the ridge segment of the East Pacific Rise (EPR) is correlated with the phase of a magmatic cycle along a given ridge segment.

TL;DR: In this paper, it was shown that the accumulated body of radiogenic isotope data for lunar rocks permit the moon to be as young as 4.44-4.51 Ga.

TL;DR: In this article, ion microprobe reveals multiple episodes of zircon growth and recrystallization within a single sample of tonalitic gneiss from the Ancient Gneiss Complex.

TL;DR: A detailed Nd isotopic study of the large and well-dated Hamersley and Michipicoten banded iron formations (BIFs) has been conducted in this article, showing that the source of much of the Fe in BIFs and Archean seawater was hydrothermal water circulating through Archean midocean ridge systems.

TL;DR: Achert horizon within the Archaean basalt pile at Kambalda, Western Australia, contains zircons from air-fall tuffs erupted as the sediment was laid down as mentioned in this paper.

TL;DR: In this paper, compositionally diverse Late Archean rocks (2.74-2.79 Ga old) from the eastern Beartooth Mountains (Montana and Wyoming) were studied and shown to have the same initial Pb, Sr, and Nd isotopic ratios.

TL;DR: A series of komatiite flows from Munro Township, Ontario, have Re and Os concentrations that range from 0.545 to 1.22, giving a crystallization age of2726 ± 93Ma and an initial187Os/186Os of0.873 ± 0.035.

TL;DR: Inverse magnetic fabrics due to magnetite are also encountered in weakly deformed limestones as mentioned in this paper, and a mineralogical model based on the property of single-domain grains to have a zero susceptibility parallel to their long axis is proposed.

TL;DR: The global Nd isotopic evidence for early mantle depletion, which shows that some enriched reservoir must have persisted for at least 300 Ma in the early Archean, is discussed in this paper.

TL;DR: In this article, a simple and precise major element mass balance is consistent with derivation of average upper mantle peridotite from a partially molten chondritic Earth by subtraction of perovskite and addition of olivine.

TL;DR: Isotopic (Sr, Nd, Pb) and trace element data are reported for samples dredged along the South-East Indian Ridge (SEIR) and confirm the existence of a geochemical province under the Indian Ocean which is distinct from the provinces observed under the North Atlantic and Pacific Oceans.

TL;DR: The characteristics and possible origin of the chondrite ALH85085 are discussed in this article, where it is found that the metal silicate and sulfide compositions are similar to those in CM-CO and Al Rais-Renazzo chondrites.