Showing papers in "Earth and Planetary Science Letters in 1973"

TL;DR: In this paper, the results of 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.

TL;DR: The solidus of a model pyrolite composition is sensitively dependent on water content and has been determined experimentally up to 40 kb, for water-saturated (6% H2O) and water-underwater (0.2%) conditions.

TL;DR: The Troodos ophiolitic complex in Cyprus has been widely regarded as a fragment of oceanic crust that was created in a mid-oceanic ridge.

TL;DR: The Himalayan mountain chain is not a direct result of the continent-continent collision, but of uplift during underthrusting along the deep crustal fracture as discussed by the authors.

TL;DR: In this article, an expression for radial thickness variations in lunar impact crater ejecta was proposed, which was inferred from available cratering data and semi-empirical calculations for approximate modeling of variations in ejecta thickness with the increasing range of lunar craters.

TL;DR: In this paper, the temperature dependence of the fractionation factor α, for oxygen isotopic exchange between silicates, magnetite and water from a theoretical point of view, was discussed, and it was shown that for anhydrous silicates and magnetite 1000lnα (mineral water) = −3.7 + B/T 2, where B is a constant, for the temperature interval 500° to 800°C.

TL;DR: The oxygen isotope data obtained from BiPO 4 samples fluorinated in silver-soldered metal lines are systematically more negative than those obtained by fluorination in a line assembled with flareless fittings.

TL;DR: In this article, the authors studied the source mechanism of the Portugal earthquake of February, 1969, based on long-period surface wave data, and the geometry of the planar distribution of the aftershocks distinguishes the fault plane from the auxiliary plane.

TL;DR: In this article, chemical data presented in this paper indicate a good correlation between P 2 O 5 and Fe 2 O 3 in some iron-rich volcanogenic sediments from the East Pacific Rise and suggest that this association is due to the reaction of phosphate in sea water with poorly crystallized hydrous ferric oxides.

TL;DR: The convergence of the Indian and Eurasian plates appears to cause relatively high stress to be transmitted across a broad area, north and east of the Himalayas, and this stress in turn causes earthquakes and renewed tectonic activity in some of the ancient Paleozoic and Mesozoic fold belts that separate more stable, aseismic blocks in Asia.

TL;DR: In this paper, a method was developed for simultaneous application of the vertical diffusion-advection model to 226Ra and 210Pb deep-water profiles, and the in-situ source terms for both isotopes were obtained as a function of the parametric upwelling velocity.

TL;DR: In this article, an experimental study was carried out at high pressures and temperatures to determine the crystallization behavior of olivine-rich basanite composition with various known water contents.

TL;DR: The activity ratio of228Th/228Ra in the open surface ocean averaged 0.21 as mentioned in this paper, which suggests that thorium is removed from surface water in about 0.7 yr.

TL;DR: Strontium isotope ratios and rare-earth element abundances have been measured in acid, intermediate and basic rocks from three late to postglacial volcanic complexes, and several other post-glacial basalts in Iceland as discussed by the authors.

TL;DR: In this article, the isotopic composition of lead was determined for two carbonaceous, two H, and two L chondrites, and the results showed that the lead ages for the Bruderheim chondrite are concordant within approximately 20%.

TL;DR: In this article, it is suggested that the lineaments are continental expressions of these fracture zones and are consistent with the current model for the evolution of the South Atlantic and the origin of the lineament as suggested here.

TL;DR: In this paper, a correlation between free air gravity and differences in crestal depth of the midocean ridge system was found. But, the correlation between gravity anomaly and changes in rate along the ridge axis was not investigated.

TL;DR: In this paper, the oxygen isotopic composition of the phosphate from fish teeth and bones has been studied in twenty four specimens of fifteen species, and the temperatures calculated from the δ18O(PO43−) by means of the Phosphoric Water isotopic temperature scale equation are within the expected range.

TL;DR: A simple paleogeographic reconstruction for the early Mesozoic era requires Borneo to have been adjacent to mainland China and Hainan as mentioned in this paper. But this reconstruction requires the opening of the basin can then be explained by a simple rotation of a small plate, which included Baysian and Natuna Islands, away from mainland China about a pole of rotation located at Latitude 13.0°N, Longitude 44. 0°E.

TL;DR: K Ar,40Ar 39Ar and Rb Sr dates are reported for minerals from the ca. 3700 my-old Isua gneisses of the Godthaabsfjord area of West Greenland as mentioned in this paper.

TL;DR: In this paper, a plot of 208 Pb/ 232 Th versus 207 pb/ 235 U gave a discordia line intersecting the concordia at 3648 ± 85my.

TL;DR: In this paper, measurements of the NRM of a 26 m long deep-sea core from the southern Indian Ocean indicated the presence of three transitions of magnetic polarity which have been identified as the upper and lower Jaramillo and the upper Olduvai on the basis of micropaleontological criteria.

TL;DR: A survey of the southern part of the Balearic Basin was conducted at a height of 600 m in 1971 as mentioned in this paper, and the results of this survey were used to define a complex kinematic pattern of the opening of the basin in terms of plate tectonics.

TL;DR: The mid-cayman rise as discussed by the authors is an axis of sea-floor spreading in the Cayman Trough, and it is the most similar to the mid-oceanic rise in morphology and sediments.

TL;DR: In this article, the authors derived the derived hysteresis ratios R sub H and R sub I for various dilute magnetic materials and used them to classify the various natural dilute materials.

TL;DR: In this article, the initial 87 Sr/ 86 Sr ratios of Tertiary and Pleistocene igneous rocks from Iceland have been determined with a typical precision of 0.00005 (2-sigma).

TL;DR: In this article, the authors measured compressive (V p ) and shear (V s ) wave velocities in 32 cores of basalt from 14 Pacific sites of the Deep Sea Drilling Project.

TL;DR: In this paper, a numerical test has been carried out on the width and postulated transform fault offsets of the mid-continent gravity high of central North America, and it was shown that the total amount of separation on the Keweenawan rifts is equal to the width of the gravity high.

TL;DR: A natural ferric gel precipitated near freshwater springs has been characterised by X-ray and electron diffraction, thermal, infra-red, magnetic and Mossbauer measurements as discussed by the authors.

TL;DR: In this article, it was shown that the mid-ocean ridge tholeiitic basalt pillows have noble gas abundance patterns which resemble the solar rare gas pattern rather than the noble gas pattern of the terrestrial atmosphere.