Showing papers in "Marine Geology in 1979"

TL;DR: In this article, Pb-210 profiles in Washington shelf sediments reveal three characteristic regions: a homogeneous surface layer (about 10 cm thick), a region where sediments are actively mixed by physical and biological processes, and a lower region of background activities.

TL;DR: In this article, the authors performed direct measurements of surf and current spectra, inshore circulation patterns, and depositional morphology in several environmentally contrasting beach localities on the high-energy coast of New South Wales, Australia.

TL;DR: In this paper, a new mathematical model of turbidity flow is described, this model having been constructed so as to investigate the interaction between the velocity and effective density of the flow, and a physical version of the model, with plausible values for the controlling parameters, is then described.

TL;DR: In this article, a suite of 64 trigger-core tops in the southeast Indian Ocean between 25-50° S and 80-140° E was examined to evaluate their possible relationships with deep-sea water masses.

TL;DR: In this article, a three-layer stratigraphy is presented: a mixed layer with intense bioturbation (upper 5-7 cm), a transition layer (extending down to 20-35 cm), and a historical layer below.

TL;DR: In this article, the authors used reflection profiles and numerous pre-Neogene samples obtained from the continental margin off northern Spain to reconstruct its Mesozoic and Cenozoic evolution.

TL;DR: In this article, the general tidal characteristics in the neighbourhood of a promotory were derived using a numerical model developed in plane polar coordinates and the same features were found for a model of the tides off the Start Point promontory using a Cartesian reference frame, and it was suggested that vorticity generated near the headland plays a key role in the dynamics of offshore tidal bank formation.

TL;DR: In this paper, the present North Adriatic continental shelf was a wide fluvio-lacustrine plain, where rivers with rather high dynamics coexisted with swamps and bogs characterized by calm water and formation of peat soils.

TL;DR: In this article, a large slide and a large slump have displaced about 250 km3 of surficial sediment from the lower continental slope onto the upper continental rise, and the slide and slump scars together cover an area of about 6000 km2; they affect only the upper few tens of meters of the sediment column.

TL;DR: A stricter definition of the terms Chenier and Chenier plain involves genetic concepts and good subsurface control that avoids pitfalls caused by superficial morphological resemblance between true chenier plains and partially buried beach ridge-strand plains (beach plains), masked by surficial salt marsh or fresh water-deltaic deposits as mentioned in this paper.

TL;DR: The GEOPROBE system as mentioned in this paper was used to collect time-series data on physical and geological parameters that are important in bottom sediment dynamics on continental shelves, in combination with current velocity profiles measured with a near bottom vertical array of electromagnetic current meters.

TL;DR: The island slope of the Cayman trench as discussed by the authors consists of a steep, 5 km high, normal faulted monocline of Miocene chalk, dissected by submarine canyons, and partially mantled by pelagic brown clay ooze.

TL;DR: In this paper, field experiments on beach-cusp formation were undertaken to document how the cuspate form develops and to test the edge-wave hypothesis on the uniform spacing of cusps.

TL;DR: The age of sea-floor phosphorites varies from Cretaceous to Recent as mentioned in this paper, and the largest phosphorite-bearing regions are situated along the west coast of Africa and America, the east coast of the U.S.A., off New Zealand and in the central part of the Northern Pacific.

TL;DR: The Amirante Passage is a narrow topographic gap near 09°S 52°E, which restricts the northward flow of the deep western boundary current (DWBC) from the Mascarene Basin into the Somali Basin in the western Indian Ocean as discussed by the authors.

TL;DR: In this article, the history of three major fluctuations in bottom water velocity during the last 160,000 years has been determined by combining detailed stratigraphy and sedimentological analyses, and the mean particle size of the carbonate-free silt fraction was selected as a sensitive, direct monitor of bottom-water velocity fluctuations.

TL;DR: The sediment-wave troughs have been rapidly filling in during most of the last 73,000 years, suggesting that a large sediment input to the trough preceded slumping as discussed by the authors.

TL;DR: In this article, a semi-continuous run of data maps covering a 2.25km length of beach monitored at 50m intervals was used to identify seven inshore states, related not only to immediate wave climate but also to antecedent morphology and wave changes.

TL;DR: In this article, the authors showed that in this region away from active plate boundaries, the sea stood at least 3 m above present sea level 132,000 ± 5,000 years ago.

TL;DR: The Miami Terrace is a drowned early to middle Tertiary carbonate platform, the outer margin of which has been deeply incised by submarine erosion subsequent to deposition of the limestone terrace.

TL;DR: In this article, the influence of coastal upwelling on sediment composition has been found in the Upper Miocene (SW Africa) and in the Lower and Middle Miocene(NW Africa).

TL;DR: A large-scale plan view of the surface of a major abyssal sediment drift, the Feni Ridge, has been obtained using the GLORIA Mk II dual, long-range side-scan sonar system as discussed by the authors.

TL;DR: In this paper, the authors presented new data from the north Queensland coastal plain which indicate that present Holocene sea level was reached about 6000 years B.P. and has not deviated significantly since then.

TL;DR: In this paper, the authors compared the Late Quaternary evolution of the Rosetta Fan and Menorca Fan in the eastern and the western Mediterranean, respectively, and found that the structural framework has been the primary factor and has largely controlled physiography and sediment input.

TL;DR: In the equatorial Atlantic, the Ceara and Sierra Leone rises lie on opposing sides of the mid-ocean ridge and are equidistant from its axis.

TL;DR: In this article, the authors compare the contribution of the Atlantic northeast trades to the deep-sea sedimentation via the deposition of soil-sized particulates from the northeast trades in terms of the total sediments and of their detrital and authigenic fractions.

TL;DR: In this paper, Radiocarbon dating indicates that these shell gravels are of Holocene age, and the faunal composition of these gravels can be related to local living faunas.

TL;DR: In this article, longitudinal wreck marks have been found to extend for up to 1 km in the direction of flow of the stronger ebb or flood tidal current, and a series of these has been recognized, all of which parallel the peak current.

TL;DR: Sediment instability has produced large submarine slides on the continental slope and rise seaward of the coast of New Jersey and the Baltimore Canyon Trough in the mid-Pliocene unconformity as mentioned in this paper.

TL;DR: In this article, an analytical study of turbidity current dynamics is presented and a one-dimensional model of the equations of motion is established for the steady flow case is considered in detail.