Offshore Transport and Sand-Body Formation: Evidence from a Steep, High-energy Shoreface, Southeastern Australia

A new small-bodied ornithopod dinosaur,Diluvicursor pickeringi, gen. et sp. nov., is named from the lower Albian of the Eumeralla Formation in southeastern Australia and helps shed new light on the anatomy and diversity of Gondwanan ornithopods. Comprising an almost complete tail and partial lower right hindlimb, the holotype (NMV P221080) was deposited as a carcass or body-part in a log-filled scour near the base of a deep, high-energy river that incised a faunally rich, substantially forested riverine floodplain within the Australian–Antarctic rift graben. The deposit is termed the ‘Eric the Red West Sandstone.’ The holotype, interpreted as an older juvenile ∼1.2 m in total length, appears to have endured antemortem trauma to the pes. A referred, isolated posterior caudal vertebra (NMV P229456) from the holotype locality, suggestsD. pickeringigrew to at least 2.3 m in length.D. pickeringiis characterised by 10 potential autapomorphies, among which dorsoventrally low neural arches and transversely broad caudal ribs on the anterior-most caudal vertebrae are a visually defining combination of features. These features suggestD. pickeringihad robust anterior caudal musculature and strong locomotor abilities. Another isolated anterior caudal vertebra (NMV P228342) from the same deposit, suggests that the fossil assemblage hosts at least two ornithopod taxa.D. pickeringiand two stratigraphically younger, indeterminate Eumeralla Formation ornithopods from Dinosaur Cove, NMV P185992/P185993 and NMV P186047, are closely related. However, the tail ofD. pickeringiis far shorter than that of NMV P185992/P185993 and its pes more robust than that of NMV P186047. Preliminary cladistic analysis, utilising three existing datasets, failed to resolveD. pickeringibeyond a large polytomy of Ornithopoda. However, qualitative assessment of shared anatomical features suggest that the Eumeralla Formation ornithopods, South AmericanAnabisetia saldiviaiandGasparinisaura cincosaltensis, Afro-Laurasian dryosaurids and possibly AntarcticMorrosaurus antarcticusshare a close phylogenetic progenitor. Future phylogenetic analysis with improved data on Australian ornithopods will help to test these suggested affinities.

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GEOMETRI PERLAPISAN BATUPASIR KONGLOMERATAN SEBAGAI SISIPAN PADA FORMASI NANGGULAN DI KALI WATUPURU DAN KALI SONGGO, PEGUNUNGAN KULON PROGO, YOGYAKARTA

KURVATEK ◽

10.33579/krvtk.v2i2.543 ◽

2018 ◽

Vol 2 (2) ◽

pp. 55-66

Author(s):

Siti Nuraini

Keyword(s):

Middle Eocene ◽

Energy Condition ◽

High Energy ◽

Late Eocene ◽

Compaction Process ◽

Grain Composition ◽

Fragment Composition ◽

Sandstone Body ◽

Sand Body ◽

Lens Geometry

Nanggulan Conglomeratic Sandstone is one of important part of Nanggulan Formation which is deposited during Middle Eocene to early Late Eocene (Saputra & Akmaluddin, 2015) or Late Oligocene (Rahardjo, 1995). The grain composition of Nanggulan conglomeratic sandstone is characterized by various rock fragments (metamorphic, igneous, sedimentary rocks) which mixture up to fine to coarse sand-sized matrix. Other materials present within the Nanggulan conglomerathic sandstone are shell fragments, coal remains, siderithic concretions which is deposited within high energy condition. Geometry of conglomeratic sandstone stratification is still being a question among the researchers due to discontinuous sand body character. To study external form of sandstone body needs to combine with internal characters such are grain texture, grain or fragment composition, sedimentary structures to predict a depositional facies. This research is dedicated to study the character of the Nanggulan conglomeratic sand body. Field geological observation was conduct to two rivers i.e Kali Watupuru and Kali Songgo where transecting the Nanggulan beds. The grain or fragments concentration of Nanggulan conglomeratic sandstone displays in various condition for example lying above an erosional surface to the bottom position, or concentrate to the upper layer. It also appears to be engaged in coarser size matrix, or displays a dense grain composition to elsewhere. Geometry of the Nanggulan conglomeratic sandstone represents a lens geometry which pinching-out to the edge of body. However, to the top of lens geometry were found steep joints cross cutting the sand layers. Initial geometry of Nanggulan conglomeratic sandstone indicates a channel fill shape due to filling sediments into the erosional feature of underlying beds. When lithification and compaction process occurred along the burial and uplifting tectonic phase, a channel fill geometry becomes lens geometry. Bulging to the centre part and thinning to the edge of sandstone body, is caused by differential compaction process. Lens geometry is believed as one example of structural trap model for sandstone reservoir. The occurrences of vertical joints to the Nanggulan conglomeratic sandstone need to be considered as seal potential within clossure trap or even more causing hydrocarbon leakings. If development of vertical joint occurs along migration process, it may be potentially leak. However, if joints already sealed parts of hydrocarbon pool may create a compartmentalization reservoir body. By doing this investigation could predict an advance reservoir modelling study using outcropp analogues. Keyword: Nanggulan conglomeratic sandstone, lens geometry, sandstone body.

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MORPHODYNAMIC VARtABILITY OF HIGH-ENERGY BEACHES

Coastal Engineering Proceedings ◽

10.9753/icce.v16.68 ◽

1978 ◽

Vol 1 (16) ◽

pp. 68 ◽

Cited By ~ 2

Author(s):

L.D. Wright ◽

B.G. Thom ◽

J. Chappell

Keyword(s):

Incident Wave ◽

Turbulent Viscosity ◽

High Energy ◽

Beach Erosion ◽

Dissipative Systems ◽

Energy Conditions ◽

Pressure Transducers ◽

Southeastern Australia ◽

Reflective Systems ◽

Bidirectional Flow

Field observations of beach and inshore morphology and of surf and inshore current spectra using an array of pressure transducers and low-inertia bidirectional flow meters interfaced with an in-field mini-computer/logging system have been replicated on several beaches in southeastern Australia under a range of energy conditions. Two broad extremes of beach conditions are distinguished spatially and temporally: (1) reflective systems In which much of the incident wave energy Is reflected from the beach face; and (2) dissipative systems with wide surf zones and high turbulent viscosity. Reflectivity increases as the ratio of wave steepness to beach (or bed) steepness decreases. Compared to steep, unbarred reflective beaches which are common in deeply indented or partially protected compart-, ments, the topography of exposed dissipative systems is more complex and varied: six time-and-environment-dependent morphologic types with different bar patterns and bar-beach relationships are recognized. The greatest total dissipation prevails In regions of most abundant inshore sediments or during and immediately after severe storms. Between the reflective and dissipative extremes there is a hierarchy of observed resonant frequencies with the highest frequency resonance occurring in the most reflective cases. Results indicate that near the beach face, motions associated with resonance at periods greater than incident wave periods exhibit strong net seaward resultants and are probably important sources of beach erosion. Reflective beaches are sensitive to resonant excitations over a wider range of frequencies and under lower energy conditions than are dissipative beaches. Hence, although reflective beaches represent the accretive end point of a "beach cycle" they are also more delicately poised with a higher potential for erosion.

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The E-ring: interactions with plasma and implications for its evolution

International Astronomical Union Colloquium ◽

10.1017/s0252921100101678 ◽

1984 ◽

Vol 75 ◽

pp. 599-602

Author(s):

T.V. Johnson ◽

G.E. Morfill ◽

E. Grun

Keyword(s):

Time Scale ◽

Particle Density ◽

High Energy ◽

Particle Removal ◽

Density Region ◽

Drag Forces ◽

Orbit Evolution ◽

History Of ◽

Ring Particle ◽

Ring Material

A number of lines of evidence suggest that the particles making up the E-ring are small, on the order of a few microns or less in size (Terrile and Tokunaga, 1980, BAAS; Pang et al., 1982 Saturn meeting; Tucson, AZ). This suggests that a variety of electromagnetic and plasma affects may be important in considering the history of such particles. We have shown (Morfill et al., 1982, J. Geophys. Res., in press) that plasma drags forces from the corotating plasma will rapidly evolve E-ring particle orbits to increasing distance from Saturn until a point is reached where radiation drag forces acting to decrease orbital radius balance this outward acceleration. This occurs at approximately Rhea's orbit, although the exact value is subject to many uncertainties. The time scale for plasma drag to move particles from Enceladus' orbit to the outer E-ring is ~104yr. A variety of effects also act to remove particles, primarily sputtering by both high energy charged particles (Cheng et al., 1982, J. Geophys. Res., in press) and corotating plasma (Morfill et al., 1982). The time scale for sputtering away one micron particles is also short, 102 - 10 yrs. Thus the detailed particle density profile in the E-ring is set by a competition between orbit evolution and particle removal. The high density region near Enceladus' orbit may result from the sputtering yeild of corotating ions being less than unity at this radius (e.g. Eviatar et al., 1982, Saturn meeting). In any case, an active source of E-ring material is required if the feature is not very ephemeral - Enceladus itself, with its geologically recent surface, appears still to be the best candidate for the ultimate source of E-ring material.

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Analysis of electron-diffraction intensity profiles using a photodiode-array detection system

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075403 ◽

1983 ◽

Vol 41 ◽

pp. 322-323

Author(s):

J. B. Warren

Keyword(s):

Electron Diffraction ◽

Diffraction Pattern ◽

Detection System ◽

High Energy ◽

Photographic Emulsion ◽

Diffraction Intensity ◽

Silicon Photodiode ◽

Photodiode Array Detection ◽

Analog To Digital ◽

Photodiode Array

Electron diffraction intensity profiles have been used extensively in studies of polycrystalline and amorphous thin films. In previous work, diffraction intensity profiles were quantitized either by mechanically scanning the photographic emulsion with a densitometer or by using deflection coils to scan the diffraction pattern over a stationary detector. Such methods tend to be slow, and the intensities must still be converted from analog to digital form for quantitative analysis. The Instrumentation Division at Brookhaven has designed and constructed a electron diffractometer, based on a silicon photodiode array, that overcomes these disadvantages. The instrument is compact (Fig. 1), can be used with any unmodified electron microscope, and acquires the data in a form immediately accessible by microcomputer.Major components include a RETICON 1024 element photodiode array for the de tector, an Analog Devices MAS-1202 analog digital converter and a Digital Equipment LSI 11/2 microcomputer. The photodiode array cannot detect high energy electrons without damage so an f/1.4 lens is used to focus the phosphor screen image of the diffraction pattern on to the photodiode array.

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Observation of Superlattice Dislocations on Cube Planes in Ni3Al

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071314 ◽

1973 ◽

Vol 31 ◽

pp. 174-175 ◽

Cited By ~ 1

Author(s):

J. M. Oblak ◽

W. H. Rand

Keyword(s):

Nearest Neighbor ◽

Antiphase Boundary ◽

Nearest Neighbors ◽

High Energy ◽

Cross Slip ◽

Octahedral Plane ◽

Trapping Mechanism ◽

Slip Traces

The energy of an a/2 <110> shear antiphase. boundary in the Ll2 expected to be at a minimum on {100} cube planes because here strue ture is there is no violation of nearest-neighbor order. The latter however does involve the disruption of second nearest neighbors. It has been suggested that cross slip of paired a/2 <110> dislocations from octahedral onto cube planes is an important dislocation trapping mechanism in Ni3Al; furthermore, slip traces consistent with cube slip are observed above 920°K.Due to the high energy of the {111} antiphase boundary (> 200 mJ/m2), paired a/2 <110> dislocations are tightly constricted on the octahedral plane and cannot be individually resolved.

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Microfabrication research at the National Submicron Facility

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074331 ◽

1983 ◽

Vol 41 ◽

pp. 86-89

Author(s):

E.D. Wolf

Keyword(s):

Integrated Circuits ◽

Particle Physics ◽

High Speed ◽

New Technology ◽

High Energy ◽

High Energy Particle ◽

New Science ◽

Wide Range ◽

Intermediate Domain ◽

Circuit Function

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.

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Void-Lattice Formation in Natural Fluorite by Electron Irradiation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100093031 ◽

1976 ◽

Vol 34 ◽

pp. 614-615 ◽

Cited By ~ 1

Author(s):

L.E. Murr

Keyword(s):

Electron Microscope ◽

Electron Irradiation ◽

Heavy Ion ◽

High Energy ◽

Stoichiometric Ratio ◽

Direct Observations ◽

Transmission Electron ◽

Anion Vacancies ◽

Cation And Anion Vacancies ◽

Lattice Formation

The production of void lattices in metals as a result of displacement damage associated with high energy and heavy ion bombardment is now well documented. More recently, Murr has shown that a void lattice can be developed in natural (colored) fluorites observed in the transmission electron microscope. These were the first observations of a void lattice in an irradiated nonmetal, and the first, direct observations of color-center aggregates. Clinard, et al. have also recently observed a void lattice (described as a high density of aligned "pores") in neutron irradiated Al2O3 and Y2O3. In this latter work, itwas pointed out that in order that a cavity be formed,a near-stoichiometric ratio of cation and anion vacancies must aggregate. It was reasoned that two other alternatives to explain the pores were cation metal colloids and highpressure anion gas bubbles.Evans has proposed that void lattices result from the presence of a pre-existing impurity lattice, and predicted that the formation of a void lattice should restrict swelling in irradiated materials because it represents a state of saturation.

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