Resuspension measured with sediment traps in a high-energy environment

Abstract. Three new species and one new genus of adherent foraminiferans have been found within bivalve borings in cobbles from the Faringdon Sponge-gravel (Upper Aptian) of south-central England. The new genus and species, Lapillincola faringdonensis is a uniserial textulariine with an initial planispiral coil and a multiple aperture. Lapillincola gen. nov. is a remarkable homeomorph of Arenonina Barnard, which was originally described as an agglutinated form. Arenonina is shown here to actually be calcareous and perforate, and thus a junior synonym of Rectocibicides Cushman & Ponton. Acruliammina parvispira sp. nov. is another uniserial textulariine with an initial coil. Bullopora ramosa sp. nov. is an adherent polymorphinid with a branching, irregular series of adherent chambers. These foraminiferans may have used the bivalve borings as spatial refuges from the abrasive, high energy environment of the Sponge-gravel.

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COASTAL ENGINEERING STUDIES FOR INSHORE MINING OF DIAMONDS AT ORANJEMUND

Coastal Engineering Proceedings ◽

10.9753/icce.v20.103 ◽

1986 ◽

Vol 1 (20) ◽

pp. 103

Author(s):

J.P. Moller ◽

K.C. Owen ◽

D.H. Swart

Keyword(s):

Mining Operation ◽

High Energy ◽

Aerial Photographs ◽

Beach Sand ◽

Data Set ◽

Wave Measurements ◽

Longshore Transport ◽

Energy Environment ◽

South West Africa ◽

Sea Wall

This paper describes a diamond mining operation on the west coast of Africa in Namibia (South West Africa, see Figures 1a and 1b), where a sea-wall of normal beach sand has been built out to a distance of more than 300 m seawards of the original coastline. The wall which runs alongshore is maintained in the high energy environment, which is characterized by northbound longshore transport rates, by means of artificial suppletion at a rate of up to and more than 300 000 m / month. Before embarking on the project the company had to be assured of the sand on the sand-wall; to allow completion of the project free of severe damage by wave action. This implied being able to predict the erosion rate of the sea-wall by the waves. The data set used consisted of wave measurements by Waverider and wave observations obtained from voluntary observing ships; aerial photographs at monthly intervals of the waterline in the study area; and soundings of the beach, sea-wall and nearshore topography by using a helicopter as a platform. Various methods of prediction and projection were used to quantify sediment movement.

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Chathamirhynchia kahuitara, a new genus and species of Late Cretaceous rhynchonellide brachiopod from the Chatham Islands, New Zealand: shell structure, palaeoecology and biogeography

Earth and Environmental Science Transactions of the Royal Society of Edinburgh ◽

10.1017/s1755691007078425 ◽

2007 ◽

Vol 98 (3-4) ◽

pp. 357-367 ◽

Cited By ~ 1

Author(s):

Daphne E. Lee ◽

Neda Motchurova-Dekova

Keyword(s):

New Zealand ◽

Shallow Water ◽

Volcanic Rock ◽

Late Cretaceous ◽

Shell Structure ◽

New Genus ◽

High Energy ◽

New Genus And Species ◽

Cardinal Process ◽

Energy Environment

ABSTRACTA new rhynchonellide brachiopod has been collected from the Kahuitara Tuff (Campanian–Maastrichtian) of Pitt Island, Chatham Islands, New Zealand. Brachiopods are extremely rare in Cretaceous rocks from New Zealand, and this new genus and species is unlike any other rhynchonellide known from Australasia or elsewhere. Chathamirhynchia kahuitara is distinguished by its small size, strong ribbing, and well-developed sulciplicate folding, and internally by a large, robust cardinal process and raduliform crura. The shell structure of C. kahuitara is shown to be of typical fine fibrous ‘rhynchonellidine’ type. This brachiopod was probably strongly attached to volcanic rock or shells in a shallow-water, high-energy environment. Implications for the biogeography of brachiopods during the Late Cretaceous are briefly discussed.

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Low Temperature Plasma Enhanced CVD of ‘Device Quality’ Silicon Dioxide.

MRS Proceedings ◽

10.1557/proc-105-71 ◽

1987 ◽

Vol 105 ◽

Author(s):

J. Batey ◽

E. Tierney ◽

T. N. Nguyen ◽

J. W. Stasiak ◽

J. Li

Keyword(s):

Three Dimensional ◽

Chemical Vapor ◽

High Energy ◽

Low Temperature Plasma ◽

Temperature Plasma ◽

Thermal Budget ◽

Direct Exposure ◽

Energy Environment ◽

Silicon Based ◽

Substrate Temperatures

AbstractAs silicon-based technologies move towards submicron dimensions, vertical and three dimensional structures, the need for reduced thermal processing becomes more evident than ever. Currently, insulator (usually SiO2) growth and deposition contribute significantly to the total thermal budget, and it is clear that this will have to be reduced in future processes. In addition, many other applications require the deposition of high quality dielectrics at very low substrate temperatures, typically ≳ 350°C. Plasma-enhanced chemical vapor deposition (PECVD) is a technique which can be used to deposit insulators at suitably low temperatures, although it tends to produce SiO2 which exhibits poor electrical and physical properties and which forms poor interfaces with semiconductor substrates. Direct exposure to the high energy environment of the plasma is generally thought to be the main reason for this.

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Search for helium in the upper atmosphere of the hot Jupiter WASP-127 b using Phoenix/Gemini

10.5194/epsc2020-253 ◽

2020 ◽

Author(s):

Leonardo A. dos Santos ◽

David Ehrenreich ◽

Vincent Bourrier ◽

Romain Allart ◽

George King ◽

...

Keyword(s):

Large Scale ◽

High Energy ◽

Upper Atmosphere ◽

Metastable Helium ◽

Atmospheric Escape ◽

Short Period ◽

Energy Environment ◽

In Transit ◽

First Time ◽

Hot Jupiter

<div class="page" title="Page 1"> <div class="layoutArea"> <div class="column"> <p>Large-scale exoplanet search surveys have shown evidence that atmospheric escape is a ubiquitous process that shapes the evolution and demographics of planets. However, we lack a detailed understanding of this process because very few exoplanets discovered to date could be probed for signatures of atmospheric escape. Recently, the metastable helium triplet at 1.083 &#956;m has been shown to be a viable window for the presence of He-rich escaping envelopes around short-period exoplanets. Our objective is to use, for the first time, the Phoenix spectrograph to search for helium in the upper atmosphere of the inflated hot Jupiter WASP-127 b. We observed one transit and reduced the data manually since there is no pipeline available. We did not find a significant in-transit absorption signal indicative of the presence of helium around WASP-127 b, and set a 90% confidence upper limit for excess absorption at 0.87% in a 0.75 &#197;&#160;passband covering the He triplet. Given the large scale height of this planet, the lack of a detectable feature is likely due to unfavorable photoionization conditions to populate the metastable He I triplet. This conclusion is supported by the inferred low coronal and chromospheric activity of the host star and the old age of the system, which result in a relatively mild high-energy environment around the planet.</p> </div> </div> </div>

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Short-lived dissolved nitrate pulses in a shallow Western Australian coastal lagoon

Marine and Freshwater Research ◽

10.1071/mf08298 ◽

2009 ◽

Vol 60 (10) ◽

pp. 1068 ◽

Cited By ~ 4

Author(s):

M. J. Lourey ◽

H. Kirkman

Keyword(s):

Primary Productivity ◽

Temporal Trends ◽

High Energy ◽

Nutrient Concentrations ◽

Winter Period ◽

Physical Forcing ◽

Nitrate Concentrations ◽

Energy Environment ◽

Carbon Recycling ◽

Western Australian

The source of nutrients that sustains abundant benthic primary productivity on Western Australian coastal reef systems is unknown, but it is possible that cycling between organic matter production and remineralisation contributes and may be enhanced by variations in the magnitude of physical forcing. We have used a 5-year nitrate dataset collected at weekly, daily and hourly temporal scales to investigate dynamics and supply mechanisms in Marmion Lagoon, Perth, Western Australia. Nitrate concentrations were variable over short time scales (hours) and formed pulses of elevated nutrient concentrations. On average, nitrate concentrations were highest during the high energy winter period (June to August) and scant wave data (June to August 1984) suggest a general correlation between wave activity and nitrate concentration. While it was not possible to definitively link variations in nitrate to wave forcing, increased energy may have promoted carbon recycling and nitrate release (possibly through abrasion of macroalgae, resuspension of detrital material or enhanced pore water exchange). Rapid uptake suggests that the nitrate pulses observed here may help sustain primary productivity in this shallow high energy environment. High temporal (hourly) variability suggests future surveys must sample at a frequency adequate to isolate long-term temporal trends from short-term background variations.

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High-energy environment of super-Earth 55 Cancri e

Astronomy and Astrophysics ◽

10.1051/0004-6361/201832700 ◽

2018 ◽

Vol 615 ◽

pp. A117 ◽

Cited By ~ 9

Author(s):

V. Bourrier ◽

D. Ehrenreich ◽

A. Lecavelier des Etangs ◽

T. Louden ◽

P. J. Wheatley ◽

...

Keyword(s):

Rest Frame ◽

High Energy ◽

X Ray ◽

Short Period ◽

Chromospheric Emission ◽

Energy Environment ◽

Short And Long Term ◽

Coronal Rain ◽

Far Ultraviolet

The high-energy X-ray to ultraviolet (XUV) irradiation of close-in planets by their host star influences their evolution and might be responsible for the existence of a population of ultra-short period planets eroded to their bare core. In orbit around a bright, nearby G-type star, the super-Earth 55 Cnc e offers the possibility to address these issues through transit observations at UV wavelengths. We used the Hubble Space Telescope to observe the transit in the far-ultraviolet (FUV) over three epochs in April 2016, January 2017, and February 2017. Together, these observations cover nearly half of the orbital trajectory in between the two quadratures, and reveal significant short- and long-term variability in 55 Cnc chromospheric emission lines. In the last two epochs, we detected a larger flux in the C III, Si III, and Si IV lines after the planet passed the approaching quadrature, followed by a flux decrease in the Si IV doublet. In the second epoch these variations are contemporaneous with flux decreases in the Si II and C II doublets. All epochs show flux decreases in the N V doublet as well, albeit at different orbital phases. These flux decreases are consistent with absorption from optically thin clouds of gas, are mostly localized at low and redshifted radial velocities in the star rest frame, and occur preferentially before and during the planet transit. These three points make it unlikely that the variations are purely stellar in origin, yet we show that the occulting material is also unlikely to originate from the planet. We thus tentatively propose that the motion of 55 Cnc e at the fringes of the stellar corona leads to the formation of a cool coronal rain. The inhomogeneity and temporal evolution of the stellar corona would be responsible for the differences between the three visits. Additional variations are detected in the C II doublet in the first epoch and in the O I triplet in all epochs with a different behavior that points toward intrinsic stellar variability. Further observations at FUV wavelengths are required to disentangle definitively between star-planet interactions in the 55 Cnc system and the activity of the star.

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COASTAL WAVE MODELING FOR JETTY REHABILITATION AT COOS BAY, OREGON

Coastal Engineering Proceedings ◽

10.9753/icce.v36.papers.89 ◽

2018 ◽

pp. 89

Author(s):

Lihwa Lin ◽

Zeki Demirbilek

Keyword(s):

High Energy ◽

Army Corps ◽

Army Corps Of Engineers ◽

Wave Modeling ◽

The Past ◽

The Pacific ◽

Coos Bay ◽

Storm Wave ◽

Energy Environment ◽

North And South

Coos Bay Inlet, located on the Pacific coast of southwestern Oregon, is protected by dual jetties constructed in 1928. Because the inlet is exposing to high energy environment, both north and south jetties have deteriorated since the initial construction. Aging, erosion of foundation, lack of effective maintenance, and channel dredging in the past have accelerated the jetty deterioration. To ensure navigation safety, the U.S. Army Corps of Engineers is presently investigating the rehabilitation and redesign of jetties. This paper is focused on numerical storm wave modeling of the existing jetties to provide input forcing information to physical model and redesign of jetties.

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Sequence Stratigraphic Modeling of the Lower Thamama Group, East Onshore Abu Dhabi, United Arab Emirates

GeoArabia ◽

10.2113/geoarabia0202179 ◽

1997 ◽

Vol 2 (2) ◽

pp. 179-202 ◽

Cited By ~ 6

Author(s):

Sabah K. Aziz ◽

Mohamed M. Abd El-Sattar

Keyword(s):

United Arab Emirates ◽

Seismic Data ◽

Depositional Environment ◽

High Energy ◽

Source Rocks ◽

Abu Dhabi ◽

Sequence Stratigraphic ◽

Reservoir Development ◽

Energy Environment ◽

Exploration Activity

ABSTRACT The Lower Cretaceous (Berriasian to Valanginian) Habshan Formation (Lower Thamama Group) of Abu Dhabi was deposited on a broad carbonate shelf. In east onshore Abu Dhabi, the Habshan Formation consists mainly of limestone and dolomite reaching a thickness of more than 1,100 feet. The depositional environment ranged from shallow-water peritidal to deeper shelf basin. The integration of seismic-stratigraphic, biostratigraphic, lithostratigraphic and electric log data reveals three sequences (I to III) and three shelf edges within the Habshan Formation in east onshore Abu Dhabi. These high energy shelfal sediments prograde toward the basin to the east and northeast with their shelf edges trending north-northwest to south-southeast. The seismic data indicates that the basin was filled in the east during the Hauterivian, after the deposition of Sequence IV (equivalent to the Zakum formation). Good reservoir development is found in the carbonates deposited in the high energy environment along the shelf edge of the Habshan sequence, particularly within the oblique and sigmoidal clinoforms, whereas potential source rocks are expected to be developed basinward. This combination renders the Habshan and Zakum sequences an attractive exploration target, both as structural and stratigraphic traps. Recent exploration activity in the area established the presence of hydrocarbons within the Habshan Sequence III in east onshore Abu Dhabi.

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