Showing papers in "Earth and Planetary Science Letters in 1971"

TL;DR: In this paper, it was shown that 210 Pb activity precipitated from the atmosphere is ideal for dating lake sediments of ⩽ 100 yr age, since lead is quickly removed from solution on to particulate matter so that the lead activity is easily measurable in lakes and forms a method of pinpointing the sediment strata accumulated in 1963-1964, the peak years of its fallout.

TL;DR: In this paper, samples of rocks from four known or suspected ophiolite complexes were compared with five groups of Cenozoic volcanic rocks using their contents of Ti, Zr and Y.

TL;DR: In this article, the authors used the Ar-40/Ar-39 dating technique on eight samples of Apollo 14 rocks (14053, 14310), breccia fragments (14321), and soil fragments (14001, 14167).

TL;DR: In this article, the authors show that the relationship between basement ridges and crustal isochrons suggests asthenosphere flow, at least under the spreading axis, away from the Iceland "hot spot" (mantle plume).

TL;DR: In this article, the authors proposed a geometrical model to explain the Gibraltar arc, which takes into account the recent geological discoveries about the Geology of this region, and the concept of Plate Tectonics.

TL;DR: In this paper, K-Ar ages have been determined by the 40 Ar/ 39 Ar total fusion technique on 19 terrestrial samples whose conventional K-ar ages range from 34 my to nearly 1700 my.

TL;DR: In this paper, the authors determined sedimentation rates of a core from the crest and two cores from the flank of the East Pacific Rise from the depth variations of their excess 230Th content.

TL;DR: Amphibolite-facies feldspathic gneisses from the Godthaab area of West Greenland give hitherto unique age and isotope data, including a Rb-Sr whole-rock isochron age of 3980 ± 170 my as discussed by the authors.

TL;DR: In this paper, a series of new high pressure garnets containing sodium and/or titanium was synthesized at a pressure of 250-300 kb of the majorite, previously found to occur as a shock produced phase in a chondritic meteorite.

TL;DR: Lunar chronology and evolution from Rb and Sr internal isochrons on Apollo 11 and 12 crystalline rock samples were studied in this paper, where the inner isochron was found to be a Rb-Sr internal isomer.

TL;DR: No evidence for a geomagnetic reversal between 30 400 and 13 300 yr ago has been found in a paleomagnetic study of sediments from Mono Lake, California, with ages controlled by 14 C dating.

TL;DR: In this paper, the authors measured the variation in direction of the horizontal component of remanent magnetisation with depth in the sediments of the South basin of Windermere, England, and concluded that the sediment of freshwater lakes contain an accurate record of the directional variations of the magnetic field during the period of sedimentation and that these variations can provide a time scale in such materials.

TL;DR: In this article, internal Rb-Sr isochron was determined on four basaltic rocks and on a basalt clast from a breccia from the Fra Mauro landing site.

TL;DR: In this paper, solid primordial condensation from low density partially excited gas for solar system origin is simulated in a lab environment, and it is shown that the resulting condensation can be used to simulate solar system origins.

TL;DR: A study of the release of 40Ar39Ar as a function of temperature indicates that the radiogenic40Ar loss which occurs on the lunar surface is consistent with a heat source which is relatively uniform for all the samples and may, in fact, be solar heating as mentioned in this paper.

TL;DR: In this article, it was shown that the radioisotope 40 K in the core of Earth's core may provide ∼ 10 20 erg/sec, 10 4 times the power required to maintain the Earth's magnetic field, and the energy from decay of 40 K will be largely transported through the oceanic crust, while decay energy of U and Th will be lost through the top of the continental crust.

TL;DR: In this article, the kinematics of the Eocene episode of compression between the Iberian and European plates are examined, and it is proposed that the boundary between the two plates extended west of the Pyrenees, along the Spanish marginal trench to end west of King's trough at a triple point junction.

TL;DR: In this paper, the earth's magnetic intensity, fluctuations in atmospheric radiocarbon activity, and climatic changes of the earth surface and of the ocean during the last 7000 yr are correlated.

TL;DR: In this paper, the authors identify the sites of miogeosynclinal and eugeosyn-clinal assemblages of various kinds in terms of plate tectonic theory.

TL;DR: In this article, a period of sustained infall of volcanic ash occurred during the interval 30 000 to 16 000 years ago, and isotopic (paleotemperature) data from the same cores indicate that a significant cooling of the atmosphere over Antarctica occurred at the same time.

TL;DR: In this paper, the 40 Ar/39 Ar age spectra were determined for 10 terrestrial rock and mineral samples whose geologic history is known from independent evidence, including biotite, feldspar, hornblende, muscovite, and granodiorite.

TL;DR: In this article, major and trace element data from low-grade isochemically metamorphosed Archaean igneous suites in Transvaal, Rhodesia, Western Australia and Canada show consistent variations from those of corresponding younger volcanic suites.

TL;DR: In this paper, the authors show that the flux of K, Rb, Cs, Pb, Ba and Th in oceanic basaltic crust created continuously along mid-ocean rises is insufficient by factors of 2 to 10 to supply the amounts required for generation of andesites and continental rocks at observed rates.

TL;DR: In this article, a graphical method for selecting the optimum parameters is presented, based on the approximate age of the sample to be dated and to a lesser extent by the K/Ca ratio.

TL;DR: In this article, a gas exchange piston velocity of 700 m/yr (equivalent to a stagnant boundary layer thickness of 60 μ) and a limit of greater than 160 cm2/sec was placed on the coefficient of vertical eddy diffusion in the 0 to 20 m depth zone.

TL;DR: Apollo 12 soils composition and derivation, finding feldspathic orthopyroxene rich rock and chemically comparable glass fragments was described in this article, using Apollo 12 soils.

TL;DR: The magnetic anomaly lineations have been identified in the North Atlantic and these lineations correlate with the magnetic time scale describing magnetic polarity reversals for the past 71 my as discussed by the authors.

TL;DR: Xe and Kr isotopes gas extraction and mass spectrometer analyses of Apollo 11 lunar soil, Murray carbonaceous chondrite and atmospheric Xe were performed by.

TL;DR: In this paper, the evolution of the Western Mediterranean basin during Tertiary time is discussed and it is proposed that it was created by a continental drift process during Middle Oligocene time, synchronously with the creation of the grabens over the continents.

TL;DR: In this article, heavy rare gases adsorption on terrigenous sediments, comparing earth atmospheric composition with meteoritic planetary primordial component, is discussed and compared with the Earth's primordial components.