Relevant bibliographies by topics / Shell deposits

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Academic literature on the topic 'Shell deposits'

Author: Grafiati
Published: 4 June 2021
Last updated: 5 March 2023

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Journal articles on the topic "Shell deposits"

1

Sakuna-Schwartz, D., P. Feldens, K. Schwarzer, S. Khokiattiwong, and K. Stattegger. "Internal structure of event layers preserved on the Andaman Sea continental shelf, Thailand: tsunami vs. storm and flash-flood deposits." Natural Hazards and Earth System Sciences 15, no. 6 (June 12, 2015): 1181–99. http://dx.doi.org/10.5194/nhess-15-1181-2015.

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Abstract. Tsunami, storm and flash-flood event layers, which have been deposited over the last century on the shelf offshore Khao Lak (Thailand, Andaman Sea), are identified in sediment cores based on sedimentary structures, grain size compositions, Ti / Ca ratios and 210Pb activity. Individual offshore tsunami deposits are 12 to 30 cm in thickness and originate from the 2004 Indian Ocean Tsunami. They are characterized by (1) the appearance of sand layers enriched in shells and shell debris and (2) the appearance of mud and sand clasts. Storm deposits found in core depths between 5 and 82 cm could be attributed to recent storm events by using 210Pb profiles in conjunction with historical data of typhoons and tropical storms. Massive sand layers enriched in shells and shell debris characterize storm deposits. The last classified type of event layer represents reworked flash-flood deposits, which are characterized by a fining-upward sequence of muddy sediment. The most distinct difference between storm and tsunami deposits is the lack of mud and sand clasts, mud content and terrigenous material within storm deposits. Terrigenous material transported offshore during the tsunami backwash is therefore an important indicator to distinguish between storm and tsunami deposits in offshore environments.
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Sakuna-Schwartz, D., P. Feldens, K. Schwarzer, S. Khokiattiwong, and K. Stattegger. "Internal structure of event layers preserved on the Andaman Sea continental shelf, Thailand: tsunami vs. storm and flash flood deposits." Natural Hazards and Earth System Sciences Discussions 2, no. 12 (December 1, 2014): 7225–67. http://dx.doi.org/10.5194/nhessd-2-7225-2014.

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Abstract. Tsunami, storm and flash event layers, which have been deposited over the last century on the shelf offshore from Khao Lak (Thailand, Andaman Sea), are identified in sediment cores based on sedimentary structures, grain size compositions, Ti / Ca ratios and 210Pb activity. Individual offshore tsunami deposits are 12 to 30 cm in thickness and originate from the 2004 Indian Ocean tsunami. They are characterized by (1) the appearance of sand layers enriched in shells and shell debris, (2) cross lamination and (3) the appearance of rip-up clasts. Storm deposits found in core depths between 5 and 82 cm could be attributed to individual storm events by using 210Pb dating in conjunction with historical data of typhoons and tropical storms and could thus be securely differentiated from tsunami deposits. Massive sand layers enriched in shells and shell debris characterize the storm deposits. The last classified type of event layer represents flash floods, which is characterized by a fining-upward sequence of muddy sediment. The most distinct difference between the storm and tsunami deposits is the lack of rip-up clasts, mud, and terrigenous material within the storm deposits. Terrigenous material transported offshore during the tsunami backwash is therefore an important indicator to distinguish between offshore storm and tsunami deposits.
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Carey, Stephen P., John E. Sherwood, Megan Kay, Ian J. McNiven, and James M. Bowler. "The Moyjil site, south-west Victoria, Australia: stratigraphic and geomorphic context." Proceedings of the Royal Society of Victoria 130, no. 2 (2018): 14. http://dx.doi.org/10.1071/rs18004.

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Shelly deposits at Moyjil (Point Ritchie, Warrnambool), Victoria, together with ages determined from a variety of techniques, have long excited interest in the possibility of a preserved early human influence in far south-eastern Australia. This paper presents a detailed analysis of the stratigraphy of the host Bridgewater Formation (Pleistocene) at Moyjil and provides the context to the shelly deposits, evidence of fire and geochronological sampling. We have identified five superposed calcarenite–palaeosol units in the Bridgewater Formation, together with two prominent erosional surfaces that may have hosted intensive human activity. Part of the sequence is overlain by the Tower Hill Tuff, previously dated as 35 ka. Coastal marine erosion during the Last Interglacial highstand created a horizontal surface on which deposits of stones and shells subsequently accumulated. Parts of the erosional surface and some of the stones are blackened, perhaps by fire. The main shell deposit was formed by probable mass flow, and additional shelly remains are dispersed in the calcareous sand that buried the surface.
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Davies, David J., and Molly F. Miller. "Paleocommunity information retrieval vs. shell accumulation mode in Paleozoic carbonates: examples from the Lebanon Limestone (Middle Ordovician), Tennessee, U.S.A." Paleontological Society Special Publications 6 (1992): 81. http://dx.doi.org/10.1017/s2475262200006419.

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Compared to their terrigenous counterparts, carbonate shell accumulations have until recently been relatively little studied to determine either descriptive or genetic classifications of shell bed types, the preservation potential of each type, or their relative ability to preserve community-level information. A partial classification of Paleozoic carbonate shell-rich soft sediment accumulations is proposed using sedimentation patterns in the Lebanon limestone of the Stones River Group. Paleoecological information preserved therein is then contrasted by shell bed type. The Lebanon represents typical Ordovician shallow to moderate subtidal carbonate shelf deposits in outcrops flanking the Nashville Dome and peritidal deposits in the Sequatchie Anticline of Eastern Tennessee; shell beds alternate with shell poor sediments (micrites, wackestones and diagenetically enhanced dolomites and clay-rich partings).None of the analyzed shell beds was strictly biological in origin; most are sedimentological although >10% are combined sedimentological/diagenetic. While the majority are single simple shell beds, >20% are amalgamated. All are thin (1 shell to 15 cm) stringers that pinch and swell showing poor lateral continuity (outcrop scale, tens to hundreds of meters) likely enhanced by burial dissolution. These shell beds differ greatly in fabric (packing/sorting), clast composition, taphonomic signature, and intensity of time averaging; thus community information retrieval is biased in predictable patterns. Virtually no shell beds show common shell dissolution or encrustation from long-term sediment surface exposure or hardground formation. Five major categories of accumulation are herein proposed using a DESCRIPTIVE, non-genetic terminology modified from previous works of DJD, as well as a Genetic interpretation for each. These are easily distinguished in the field and are also discriminated by Q-mode cluster analysis.Categories include, in decreasing frequency of occurrence: 1. SHELL GRAVELS; Storm/“event” beds: Sharp bases; poorly sorted coarse basal bioclasts and/or intraclasts, often with no preferred orientation; clasts fine upward to comminuted shell material and micrite. Horizontal platy brachiopods often cap the beds. High diversity and a wide range in shell alteration is represented, from whole unaltered brachiopods to minor abraded fragments, indicating extreme time averaging and poor resolution of short-term community dynamics. 2. COMMINUTED SHELLY LS; Current/ripple concentrations: Small tidal channel fill and discrete ripple trough accumulations are composed of cross-stratified bioclastic deposits with local concentrations of rip-ups. Beds are not graded; typically clasts are abraded, rounded and concordant with cross-beds. Intense time averaging and mixing of discrete communities is inferred due to continual reworking in these background deposits. 3. SHELL/CEMENT LS; Early cementation beds: Intense early diagenetic alteration is inferred due to red discoloration and rapid intergranular cementation; some beds show diagenetic micritic rinds. Beds may be brecciated and show deep burial stylolitization cutting bioclasts and cement. They may represent zones of preferred early cementation rather than a change in shell accumulation rate. Many shells from some beds show little postmortem alteration; these units may preserve much of the original community structure. 4. DENSE SHELL PAVEMENTS; Subtidal surficial pavements: Single layers of shells, commonly concave down, overlie mudstones/wackestones with no basal erosion. No obrution deposits were noted. Bioclasts are typically disarticulated and reoriented, but are not substantially abraded, broken, or dissolved. Diversity is low. Only minor temporal and lateral community mixing with small environmental fluctuation is indicated. 5. VERTICALLY IMBRICATE SHELLY LS; High energy beach zones: Platy whole and major fragments of brachiopods are deposited in low diversity, high angle imbricate beds. Less postmortem reworking and time averaging is evident compared to types 1 and 2.Thus, the most common (physically reworked) shell bed types show the most intense loss of short-term paleocommunity information. There are surprisingly few insitu community pavements or obligate long-term accumulations. This pattern differs from some described Ordovician carbonates, which may contain common community beds or hardgrounds/hiatal accumulations. This implies a relatively low rate of net sediment accumulation on a shallow, periodically wave swept shelf, and no major flooding surfaces or other indications of significant sea level change. Delineation of the sequence stratigraphic position of these carbonates is enhanced from this type of integrated community/biostratinomic analysis.
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Corcoran, P. L., and L. N. Moore. "Subaqueous eruption and shallow-water reworking of a small-volume Surtseyan edifice at Kakanui, New Zealand." Canadian Journal of Earth Sciences 45, no. 12 (December 2008): 1469–85. http://dx.doi.org/10.1139/e08-068.

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Kakanui volcaniclastic deposits on the South Island of New Zealand are the remnants of two late Eocene to early Oligocene Surtseyan-type cones. Eruptive-dominated material of the (i) stratified tuff and lapilli tuff, and (ii) lapilli tuff breccia lithofacies and post-eruptive debris of the (iii) shell-rich tuff and lapilli tuff, and (iv) chaotic and cross-bedded tuff and lapilli tuff lithofacies compose the deposits. The 9–250 m thick stratified tuff and lapilli tuff contains grain-flow deposits originating from low-volume tephra jets and local thinning and fining upward sequences that formed from density currents during sustained uprush. The lapilli tuff breccia, up to 4.5 m thick, contains inward-dipping beds deposited via debris flows along inner-cone walls. Burrows and articulated shells in the 2–4 m thick shell-rich tuff and lapilli tuff indicate volcanic quiescence and low sedimentation rates, whereas shell fragments upsection signal increased wave and current activity. Burrows, pyrite concretions, and mudstone in the lower part of the 26 m thick chaotic tuff and lapilli tuff indicate suspension deposition and cessation in pyroclastic volcanism. High-angle trough cross-beds and limestone rip-up fragments upsection are consistent with wave-induced current reworking. The depositional model involves a Surtseyan-type eruption on a continental shelf, followed by colonization of organisms on the tops of planed-off cones. The Kakanui deposits comprise a cluster of cones constituting part of a late Eocene – early Oligocene monogenetic volcanic field. The Kakanui succession provides an opportunity to study deposits that form from explosive subaqueous pyroclastic eruptions and wave-dominated deposition and erosion.
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Meldahl, Keith H. "Origin of Shell Beds and Evolution of a Shelly Sand Spit, Bahia la Choya, Northern Gulf of California." Paleontological Society Special Publications 2 (1987): 189–99. http://dx.doi.org/10.1017/s2475262200004810.

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An actively prograding shelly sand spit forms the eastern margin of Bahia la Choya, northern Gulf of California. Shell-rich deposits exposed on the eastern side of the spit record previous phases of spit growth. Analysis and comparison of faunal composition, biofabric and shell preservation from the beach, estero mouth bar, and the fossil spit deposits suggest 3 major phases of spit evolution: (1) southward progradation of the spit tip/estero mouth bar (lower shell bed), (2) deposition of washover lobes during a major storm (upper shell bed), and (3) eolian accretion (spit crest). A 1300 ± 50 y.b.p. radiocarbon date on a bivalve shell from the storm shell bed provides a maximum age for the storm event.
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Vermeij, Geerat J. "The oyster enigma variations: a hypothesis of microbial calcification." Paleobiology 40, no. 1 (2014): 1–13. http://dx.doi.org/10.1666/13002.

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Oysters, whose inner shell layer contains chambers, vesicles, and sometimes chalky deposits, often have extraordinarily thick shells of large size, prompting the idea that there is something unusual about the process of shell fPormation in these and similarly structured bivalves with the oyster syndrome. I propose the hypothesis that calcifying microbes, especially sulfate-reducing bacteria growing on organic substrates in fluid-filled shell-wall chambers, are responsible for shell calcification away from the shell-secreting mantle of the host bivalve. Other phenomena, including the formation of cameral deposits in fossil cephalopods, the cementation of molluscs and barnacles to hard substrata, the formation of a calcified intriticalx on the shell's exterior, and cementation of objects by gastropods on the shell for camouflage, may also involve calcifying bacteria. Several lines of inquiry are suggested to test these hypotheses.
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Dattilo, Benjamin F., Carlton E. Brett, Cameron J. Tsujita, and Robert Fairhurst. "Sediment supply versus storm winnowing in the development of muddy and shelly interbeds from the Upper Ordovician of the Cincinnati region, USAThis article is one of a series of papers published in this Special Issue on the theme The dynamic reef and shelly communities of the Paleozoic. This Special is in honour of our colleague and friend Paul Copper." Canadian Journal of Earth Sciences 45, no. 2 (February 2008): 243–65. http://dx.doi.org/10.1139/e07-060.

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Shell-bed development can be a product of complex sedimentological and biological factors. The Upper Ordovician sediments near Cincinnati, Ohio constitute a succession of thinly interbedded shelly carbonates and mudrocks. Despite years of study, the development of Cincinnatian shell beds and metre-scale cycles has, until recently, been attributed solely to storm reworking. This “storm-winnowing model” treats shells as passive sedimentary clasts, ignoring other factors of shell-bed development. A recently proposed alternative is Brett and Algeo’s idea that these shell beds grew during long periods of normally low sedimentation, while most mud accumulated during brief periods of high sedimentation. Under this “episodic starvation model,” any storms would winnow pre-existing muds and shell beds alike. We tested both models in the Edenian–Maysvillian (early to mid Katian) strata of the Cincinnati region by compiling observations on their petrologic, taphonomic, and paleoecologic characteristics. The storm-winnowing model does not explain several observed features that the episodic starvation model does, including (i) storm-related sedimentary structures in mudrocks and limestones; (ii) lack of a sufficiently fossiliferous precursor deposit to winnow; (iii) deep-water faunas in grainstones; (iv) mixed taphonomic conditions of shell-bed fossils; (v) ubiquitous discontinuity surfaces; (vi) carbonate concretion horizons; (vii) unwinnowed shell beds; and (viii) micrite in packstones. Episodic starvation is a superior explanation because it explains all of these features and allows for the complex interplay of other environmental and biological factors that contribute to shell-bed growth. It may also be applicable to other deposits, previously interpreted as tempestites.
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Sparks, Darrell, and I. E. Yates. "Anatomy of Shuck Abscission in `Desirable' Pecan." Journal of the American Society for Horticultural Science 120, no. 5 (September 1995): 790–97. http://dx.doi.org/10.21273/jashs.120.5.790.

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Cellular changes associated with shuck dehiscence and markings deposited on pecan [Carya illinoinensis (Wangenh.) C. Koch] shells were examined by scanning electron and light microscopy. Fruit were sampled at three stages of maturity: 1) shuck and shell fused, 2) sutures separated (shuck opening), and 3) vascular system separated from shuck. Shuck dehiscence involved temporally regulated abscission events with shuck-shell, then shuck-suture, and finally shuck-vascular system separation. Abscission events occurred in a tissue zone common to and continuous among all three separation sites, even though segregated in time. Also, similar cell types and cellular changes were common to the three events. Thus, temporal segregation of abscission events was not due to differences in either tissue type or cellular modifications, but to maturation rate. Structures to become shell markings were single globules filling cells of the shuck inner tissue zone before shuck-shell separation. These globules were deposited on the shell at shuck-shell separation and were morphologically similar to deposits stuck to the dorsal shuck surface. Globules were partitioned differentially between the shuck and shell during shuck-shell separation. Thus, the inner zone of the shuck is an important tissue in pecan nut maturation; it functions as the site for dehiscence and provides markers for cultivar identification.
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Roy, Peter S. "Shell Hash Dating and Mixing Models for Palimpsest Marine Sediments." Radiocarbon 33, no. 3 (1991): 283–89. http://dx.doi.org/10.1017/s0033822200040303.

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The dating of palimpsest marine sediments using broken shell fragments (shell hash) is considered to be a necessary but unreliable technique because of the mixed age of the fragments. An analysis of geological mixing models and radiocarbon data on shell hash from sandy sediments on the southeast Australian coast and shelf are used to examine the possibility for simulating the depositional processes, and thus, to better understand the age structure of the deposits.
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Dissertations / Theses on the topic "Shell deposits"

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Wheadon, C. J. D. (Christopher James Daniel), and n/a. "A systemic approach to understanding prehistoric shell-bearing deposits in New Zealand: a case study from Shag Point, North Otago." University of Otago. Department of Anthropology, 2002. http://adt.otago.ac.nz./public/adt-NZDU20070507.115526.

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This thesis describes a systemic approach to the study of shell remains, using material from the site of Shag Point (J43/11), in North Otago. This approach analyses the relationship between sampling, identification, quantification, and site formation processes. An historical and methodological framework is used to assess the analysis of shell-bearing deposits in New Zealand, and provide innovative solutions to bias. Historical research outlines the common research methods in New Zealand, which are relevant to Shag Point. Methodological research outlines the range of potential research methods used in the study of shell-bearing deposits. Reviewing the data from Shag Point, sampling, identification, quantification, and site formation processes are used to assess the quality of data from the site. Data from coastal sites are commonly used to generate regional level syntheses. These syntheses do not deal with all of the possible sources of bias in shell-bearing deposits. Cumulative sampling is used to assess representativeness. The data from Shag Point are indicative of a representative sample. The site is compared to three other coastal southern South Island assemblages: the nearby Shag River Mouth, Pleasant River, and Pounawea. The data from Shag River Mouth may be representative; the same cannot be said for the Pleasant River and Pounawea archaeological assemblages, thus hampering regional-level syntheses.
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Chandupatla, Udaya B. "Evaluation of power deposited in a homogenous head model for clam-shell type cellular phones." FIU Digital Commons, 2006. http://digitalcommons.fiu.edu/etd/2106.

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The fundamental dosimetric quantity used to measure the level of exposure due to cellular phones is the Specific Absorption Rate (SAR). The compliance of a device to the exposure limit is determined by following the guidelines described in IEEE measurement standards. The compliance assessment process can be quite complicated and time consuming, due to the many different test conditions that have to be considered and the slow speed of the measurement equipment. Depending on the frequency, use configuration of the device and form factor the SAR values can vary significantly from test case to test case even for the same device. This work shows that for a particular form factor, indicated as clam shell, where the phone is made of two halves that rotating around a hinge, one of the required test condition, described as tilt position, always provides lower SAR values than touch position, the other test condition. Different frequencies, antenna locations and antenna types have been considered. The results obtained with the well-known Finite Difference Time-Domain (FDTD) method have been validated with measurements. A robotic assessment tool (DASY4) is used for measurement purpose.
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De, Decker RH. "The geological setting of diamondiferous deposits on the inner shelf between the Orange River and Wreck Point, Namaqualand." Master's thesis, University of Cape Town, 1986. http://hdl.handle.net/11427/26236.

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Moriarty, Julia M. "Transport and Fate of Sediment on the Waipaoa River Continental Shelf: Implications for the Formation and Reworking of Flood Deposits." W&M ScholarWorks, 2012. https://scholarworks.wm.edu/etd/1539617920.

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As part of a large interdisciplinary study, particulate fluxes in the Waipaoa River sedimentary system in New Zealand have been studied from the terrestrial headlands of the catchment to the oceanic basin over timescales spanning storm events, seasons, and the Holocene. Here, we complement prior efforts by evaluating the formation and reworking of riverine deposits during episodic flood and wave events, and considering their role in accumulation patterns created over longer timescales on the Waipaoa shelf. Using a numerical hydrodynamic and sediment transport model, sediment fluxes and deposition were analyzed from January 2010 through February 2011. A version of the three dimensional ROMS-CSTMS (Regional Ocean Modeling System – Community Sediment Transport Modeling System) was used to investigate the spatial and temporal variability of sediment fluxes on the Waipaoa shelf. The model could account for river input, waves, winds, larger-scale currents, tides, multiple sediment classes and a multi-layered seabed. Sediment sources to the water column included both the river plume and resuspension from the seabed. For model stability and to prevent the reflection of the river plume at the open boundary, the Waipaoa shelf model was nested within a larger-scale New Zealand ocean model. Model inputs were based on observations and model estimates, depending on availability.
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Rau, Grant. "A geological evaluation of marine diamond placer deposits on the central Namibian inner shelf : a case study of the Hottentot Bay area." Thesis, Rhodes University, 2004. http://hdl.handle.net/10962/d1007554.

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This study focusses on the marine diamond placers within Exclusive Prospecting Licence 1950 and Mining Licence 103a, located northwest of the north-facing Hottentot Bay which is 60 km north of Lüderitz, along the central Namibian coastline. The thesis follows the natural geological evolution of the marine placer deposit from primary source, through alluvial and/or glacial transportation, concentration along the coastline by wave, aeolian and alluvial/sheet-wash processes and finally marine diamond placer preservation. All of these processes are reviewed as they are important in understanding of the evolution marine placer deposits. The poly-cyclic role of coastal aeolian, alluvial, and marine processes, in marine placer enrichment is shown to be particularly important in considered target identification and prioritisation. A detailed bathymetric, sonographic and seismic interpretation, is an integral part of diamond placer exploration, and was used to examine and describe surficial and sub-bottom characteristics within the study area. Marine placers are formed along palaeo-strandlines during periods of marine transgression and regression and are therefore fundamental in marine placer exploration. A detailed bathymetry map, compiled for this study, of the area between Lüderitz Bay and Clara Hill, provides the foundation for a detailed terrace level investigation. Regionally, twelve well-developed stillstand levels are identified, nine of which fall into the study area. These interpretations are compared with global eustatic as well as terrace and resource/reserve levels in the Lüderitz area and are found to correlate well. Sediment dynamic studies involve the use of accredited application software for wave refraction modelling, to determine the wave angle and orbital wave velocity at the seabed. Bedload velocities, required to move diamonds of specific sizes, can be empirically determined and therefore areas of diamond entrainment and deposition can be modelled and target features delineated and prioritised. These detailed interpretations provide a sound platform for evaluating diamond placer process models in the study area. By integrating both previously published and newly formulated ideas, a revised, holistic model for the formation of marine diamond placer deposits in central Namibian is postulated. The proposed model is tested by comparing it to the lateral distribution of presently defined resource/reserve areas in the Lüderitz area and shows a close correlation with most of these enriched deposits. Based on this model, a matrix for the delineation and prioritisation of marine placer deposits is developed and the best target features within the study area are identified.
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Lodewyks, Therisia. "Siesmic Stratigraphy of Upper Pleistocene gravel and holocene mudbelt deposits between wreck point and the kamma river on the western shelf of South Africa." Master's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/4208.

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This project aims to provide a better understanding of the deposition of Quaternary and Holocene sediments along the west coast of Southern Africa between Wreck Point at approximately 28º50.00′S and the Kamma River at approximately 29º20.00′S, based primarily on seismic stratigraphy. The high resolution airgun seismic survey performed by De Beers Marine during 1998 was interpreted based on seismic stratigraphic principles and the chronology of the seismic profiles was based on correlation to radiocarbon-dated gravity cores from offshore the Holgat River determined by Herbert (2009). Seismic profiles were interpreted to the north and south of the central Holgat River sequence with the identified Type 1 Sequence divided into systems tracts. The Type 1 Sequence Boundary represents a major erosional unconformity formed as a result of tectonic uplift and a relative drop in sea level. A wave-cut knick point provides accommodation space for the deposition of Pleistocene and Holocene sediment above the erosional unconformity. The Lowstand Systems Tract (LST) consists of a condensed gravel lag. The LST is divided into subunits where possible which reflect the complex depositional history as the gravel lag was variably reworked as the strandline migrated across the shelf in response to late Pleistocene sea-level fluctuations. This study attempts to delineate some of the more distinctly different units within the economically important gravel body of the LST. The extent and seismic character of five subunits were identified within the complex LST. The Transgressive Systems Tract (TST) formed after a rapid rise in sea level between 19 and 7 thousand years ago (ka). Two transgressive packages were formed as sea level migrated landward. An older deeper water package was identified and labelled Unit 4 while a younger shallower water package was identified upslope, Unit 5, as the mudbelt depocentre migrated landward. The Highstand Systems Tract (HST) is characterized by a set of prograding sigmoidal clinoforms having formed in response to increasingly limited accommodation space after 5.5 ka. Clinoforms, seismic reflectors with slightly higher amplitude than the underlying units, represent depositional hiatuses during periods of lower sedimentation rates. The HST units show southward progradation as accommodation space around the Orange River Mouth became limited. The resulting sequence startigraphy and stratal geometries of the studied sequence are controlled by sea level fluctuation, accommodation space and sediment supply.
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Bohrer, Arndt. "Entwicklung eines internetgestützten Expertensystems zur Prüfung des Anwendungsbereichs urheberrechtlicher Abkommen." Kassel : Kassel Univ. Press, 2003. http://deposit.d-nb.de/cgi-bin/dokserv?idn=97032314X.

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Delaine, Maxence. "La composition des thèques d'amibes xénosomiques : utilisation potentielle comme bio-indicateur des dépôts de particules d’origine atmosphérique." Thesis, Besançon, 2016. http://www.theses.fr/2016BESA2017/document.

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Les amibes à thèque, également appelés thécamoebiens, sont des micro-organismes unicellulaires, qui construisent une enveloppe rigide, appelée thèque (Adl et al., 2012). Ces thèques ont des tailles, formes et natures très variées (Ogden & Hedley, 1980). Les récentes études sur la composition des thèques ont conduit à émettre l’hypothèse que les amibes xénosomiques (constituées de particules exogènes), peuvent constituer des bio-indicateurs pertinents de la diversité particulaire de l’environnement minéral, organique et biologique dans lequel elles évoluent.L’objectif principal des recherches menées au cours de cette thèse vise donc à caractériser la composition des thèques d’amibes xénosomiques et à en évaluer leur utilisation potentielle en tant que bio-indicateurs des dépôts de particules d'origine atmosphérique. Pour cela, des thèques d’amibes ont été analysées in situ en conditions naturelles et après dépôts artificiels de particules minérales allochtones.Ces travaux permettent de dégager plusieurs conclusions majeures :(1) La taille des particules minérales intégrées dans la thèque xénosomique de Bullinularia indica est similaire à celle des particules minérales transportées dans l'atmosphère; (2) les particules minérales intégrées dans les thèques sont des silicates stables dans les conditions physico-chimiques régnant dans les tourbières, les bryophytes et les sols étudiés; (3) certains minéraux comme la phlogopite, même lorsqu’ils sont présents en de fortes concentrations, ne sont jamais intégrés par les amibes; (4) la combinaison des observations portant sur la taille, la forme et la nature des particules utilisées par des amibes xénosomiques permet de poser les bases de l'utilisation des amibes à thèques pour la bio-indication de la diversité particulaire atmosphérique récente ou ancienne
Theca-like amoebae, also called thecaamoebius, are unicellular microorganisms, which construct a rigid envelope called theca (Adl et al., 2012). These themes have very varied sizes, shapes and natures (Ogden & Hedley, 1980). Recent studies on the composition of the themes have led to the hypothesis that xenosomal amoebae (constituted by exogenous particles) can constitute relevant bio-indicators of the particulate diversity of the mineral, organic and biological environment in which they evolve . The main objective of the research carried out during this thesis is therefore to characterize the composition of the xenosomal amoebae and to evaluate their potential use as bioindicators of deposits of atmospheric particles. For this purpose, amoeba theae were analyzed in situ under natural conditions and after artificial deposits of allochtonous mineral particles. Several major conclusions can be drawn from this work: (1) The size of the mineral particles integrated in the xenosomal theca of Bullinularia indica Is similar to that of mineral particles transported into the atmosphere; (2) the mineral particles integrated into the thecs are stable silicates under the physico-chemical conditions prevailing in the peatlands, bryophytes and soils studied; (3) some minerals such as phlogopite, even when present in high concentrations, are never integrated by amoebae; (4) the combination of observations on the size, shape and nature of the particles used by xenosomic amoebae forms the basis for the use of tea amoeba for bioindication of recent or former atmospheric particulate diversity
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Suarez, Suzette V. "The outer limits of the continental shelf : legal aspects of their establishment /." Berlin [u.a.] : Springer, 2008. http://deposit.d-nb.de/cgi-bin/dokserv?id=3103207&prov=M&dok_var=1&dok_ext=htm.

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Мельничук, П. М. "Особливості геологічної будови і перспективи нафтогазоносності нижньокрейдових відкладів північно-західного шельфу Чорного моря." Thesis, Івано-Франківський національний технічний університет нафти і газу, 2005. http://elar.nung.edu.ua/handle/123456789/4064.

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Роботу присвячено вияшіенню особливостей геологічної будови нижньокрейдових відкладів північно-західного шельфу Чорного моря і визначенню перспектив їх нафтогазоносності та пріоритетних напрямків подальших пошуково-розвідувальних робіт. Побудовано структурно-тектонічні карти покрівлі та підошви нижньокрейдових відкладів. Виділено типи літофацій та побудовані карти їх просторового поширення і розвитку порід-колекторів. Проведено районування території поширення нижньокрейдових відкладів за ступенем їх перспективності на підставі критерійних ознак нафтогазоносності та щільності початкових прогнозних ресурсів вуглеводнів, за результатами яких побудовано карти перспектив нафтогазоносності готерів-верхньоаптських і верхньоальбських відкладів. Обґрунтовано на підставі рейтингової оцінки пріоритетні напрямки геологорозвідувальних робіт на нафту і газ та першочергові об’єкти для проведення параметричного і пошукового буріння та пошукових і детальних сейсморозвідувальних робіт.
Работа посвящена изучению особенностей геологического строения нижнемеловых отложений северо-западного шельфа Черного моря, определению перспектив их нефтегазоносности и приоритетных направлений дальнейших поисково-разведочных работ на нефть и газ. На основании современных геолого-геофизических материалов и данных глубокого бурения построены структурно-тектонические карты по кровле и подошве для отложений этого возраста. Выделены типы литофаций и построены карты их пространственного развития. Рассмотрены критерии перспектив нефтегазоносности нижнемеловых отложений. Проведено районирование территории распространения нижнемеловых отложений за степенью их перспективности на основании критериев нефтегазоносности и плотаости начальных прогнозных ресурсов углеводородов, по результатам которых построены карты перспектав нефтегазоносности нижнемеловых отложений. Обосновано на основании рейтинговой оценки приоритетные направления геологоразведочных работ на нефть и газ и первоочередные объекты для проведения параметрического и поискового бурения и поисковых и детальных сейсморазведочных работ. Выявлено, что наиболее нефтегазоперспективные зоны приурочены к Каркинитскому и Каламитскому газоносным районам, общие ресурсы углеводородов которых соответственно для нижнемеловых отложений составляют 283,6 и 120,9 млн.т. у.т. Менее перспективными являются территории Нижнепрутско-Килийского (57,2 млн.т. у.т.), Алуатско-Тузловского (39,4 млн.т. у.т.) нефтегазоносных районов и Таврийского (3,9 млн.т. у.т.) перспективного района. Бурение параметрических и поисковых скважин в первую очередь рекомендуется проводить на площадях: Угловая, Рифтовая, Осетровая, Штормовая, Янтарная, Олимпийская, Краевая, Комсомольская, Зональная, Губкина, Корнилова, Нахимова, Каламитская и Гордиевича.
The thesis is devoted to the exposure of geological structure features of low cretaceous deposits of the Black sea north-western shelf and determination of perspectives of their oil and gas bearing and priority directions of subsequent searching-reconnaissance works. The structural-tectonic cards of roof and sole of low cretaceous deposits are built. The types of litofasciae are selected and cards of their spatial distribution and development of breeds-collectors are built. Districting of territory distribution of low cretaceous deposits is conducted after the degree of their perspectives on the basis of criterion signs of oil and gas bearing and closeness of initial prognosis resources of hydrocarbons as a result of which the cards of prospects of oil and gas bearing are built basal and upper albian deposits. On the basis of rating estimation priority directions of geological survey works on an oil and gas and primary objects for conducting of the parametric and searching drilling and detailed seismic reconnaissance works are defined.
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Books on the topic "Shell deposits"

1

Seck, Emmanuel. Diversité floristique dans la lagune de Joal-Fadiouth. Dakar, Senegal: ENDA, 2010.

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United States. Congress. House. Committee on Resources. Use of sand, gravel, and shells of outer continental shelf: Report (to accompany H.R. 3972) (including cost estimate of the Congressional Budget Office). [Washington, D.C: U.S. G.P.O., 1998.

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United States. Congress. House. Committee on Resources. Use of sand, gravel, and shells of outer continental shelf: Report (to accompany H.R. 3972) (including cost estimate of the Congressional Budget Office). [Washington, D.C: U.S. G.P.O., 1998.

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Derkachev, A. N. Mineralogicheskie indikatory obstanovok prikontinentalʹnogo osadkoobrazovenii︠a︡ zapadnoĭ chasti Tikhogo okeana: Environmental mineralogical indicators of near-continental sediment formation within Pacific Ocean western part. Vladivostok: Dalʹnauka, 2010.

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Ivanova, A. M. Kaĭnozoĭskiĭ rudogenez v shelʹfovykh oblasti︠a︡kh Rossii. Edited by Smirnov, A. N. (Aleksandr Nikolaevich), doktor geologo-mineralogicheskikh nauk, author, Ushakov V. I. author, and Ivanov, V. L. (Vladimir Leonidovich), editor. Sankt-Peterburg: VNIIOkeangeologii︠a︡, 2005.

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Marine Geoscience Group (South Africa), ed. The geological setting of diamondiferous deposits on the inner shelf between the Orange River and Wreck Point, Namaqualand. Rondebosch: Marine Geoscience Unit, Department of Geology, University of Cape Town, 1986.

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Grosz, A. E. Titanium-zirconium-rare-earth placer resources potential of surficial sediments on the Atlantic Continental Shelf offshore of New York, Rhode Island, and southern Massachusetts. [Reston, VA]: U.S. Dept. of the Interior, Geological Survey, 1991.

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M, Kelly William, New York State Geological Survey., and Geological Survey (U.S.), eds. Titanium-zirconium-rare-earth placer resources potential of surficial sediments on the Atlantic Continental Shelf offshore of New York, Rhode Island, and southern Massachusetts. [Reston, VA]: U.S. Dept. of the Interior, Geological Survey, 1991.

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Grosz, A. E. Titanium-zirconium-rare-earth placer resources potential of surficial sediments on the Atlantic Continental Shelf offshore of New York, Rhode Island, and southern Massachusetts. [Reston, VA]: U.S. Dept. of the Interior, Geological Survey, 1991.

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Grosz, A. E. Titanium-zirconium-rare-earth placer resources potential of surficial sediments on the Atlantic Continental Shelf offshore of New York, Rhode Island, and southern Massachusetts. [Reston, VA]: U.S. Dept. of the Interior, Geological Survey, 1991.

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Book chapters on the topic "Shell deposits"

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Hendricks, Robert, and Alex Hodson. "Luminescence Dating, Shell-Rich Deposits." In Encyclopedia of Scientific Dating Methods, 431–35. Dordrecht: Springer Netherlands, 2015. http://dx.doi.org/10.1007/978-94-007-6304-3_262.

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Hendricks, Robert, and Alex Hodson. "Luminescence Dating of Shell-Rich Deposits." In Encyclopedia of Scientific Dating Methods, 1–7. Dordrecht: Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-6326-5_262-1.

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Beovide, Laura, and Sergio Martínez. "Natural Shell Deposits from a Río de la Plata Estuarine Beach, Uruguay: Formation Processes and Archaeological Implications." In Topics in Geobiology, 151–68. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-20625-3_9.

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Wells, Lisa. "Radiocarbon Dating of Holocene Tidal Marsh Deposits." In AGU Reference Shelf, 497–502. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/rf004p0497.

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Bartosiewicz, László, Lydia Zapata, and Clive Bonsall. "A Tale of Two Shell Middens: The Natural versus the Cultural in “Obanian” Deposits at Carding Mill Bay, Oban, Western Scotland." In Integrating Zooarchaeology and Paleoethnobotany, 205–25. New York, NY: Springer New York, 2009. http://dx.doi.org/10.1007/978-1-4419-0935-0_9.

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Selley, Richard C. "Shelf deposits: carbonate and terrigenous." In Ancient Sedimentary Environments, 184–210. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4615-5421-9_8.

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Selley, Richard C. "Shelf deposits: carbonate and terrigenous." In Ancient Sedimentary Environments, 184–210. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-1233-5_8.

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Selley, Richard C. "Shelf deposits: carbonate and terrigenous." In Ancient Sedimentary Environments, 184–210. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4684-7304-9_8.

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Sowers, Janet M. "Correlating Quaternary Landforms and Deposits to Global Climate Change." In AGU Reference Shelf, 425–26. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/rf004p0425.

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Hemphill-Haley, Mark A., Thomas L. Sawyer, Peter L. K. Knuepfer, Steven L. Forman, and Ivan G. Wong. "Timing of Faulting Events from Thermoluminescence Dating of Scarp-Related Deposits, Lemhi Fault, Southeastern Idaho." In AGU Reference Shelf, 541–48. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/rf004p0541.

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Conference papers on the topic "Shell deposits"

1

Busch, James, M. J. Soreghan, Kirsten de Beurs, Michael McGlue, Ishmael Kimirei, and Andrew S. Cohen. "THE ENIGMATIC QUATERNARY SHELL BED DEPOSITS OF LAKE TANGANYIKA, TANZANIA: A STORY OF ANTHROPOGENIC OR ENVIRONMENTAL CHANGE?" In GSA Annual Meeting in Denver, Colorado, USA - 2016. Geological Society of America, 2016. http://dx.doi.org/10.1130/abs/2016am-280883.

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Bergeron, Lauren, Madeline S. Marshall, and Kimberly Lau. "STRATIGRAPHIC INSIGHTS FROM PERMIAN SHELL BEDS: COMPARISON OF FRANSON MEMBER DEPOSITS OF THE PERMIAN PHOSPHORIA ROCK COMPLEX, IDAHO." In GSA Connects 2022 meeting in Denver, Colorado. Geological Society of America, 2022. http://dx.doi.org/10.1130/abs/2022am-381333.

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Cuenca-Alvarez, R., H. Ageorges, and P. Fauchais. "Stainless Steel Coatings Alumina Reinforced by Plasma Spraying Mechanofused Particles." In ITSC2003, edited by Basil R. Marple and Christian Moreau. ASM International, 2003. http://dx.doi.org/10.31399/asm.cp.itsc2003p0707.

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Abstract Stainless steel particles have been covered with an alumina shell by the mechanofusion process in order to reinforce stainless steel coatings by uniformly distributed alumina particles. Two stainless steel particle size distributions (PSD) in the range of 65 µm and 120 µm were tested. It was found that the mechanical energy input induced a spherical shape of the final composite particles with a controlled shell thickness (3 µm and 2 µm respectively) without forming new phases that usually take place during the mechanofusion process. The new spherically-shaped composite particles were sprayed in air with a D.C. plasma torch working with an Ar/H2 mixture as plasma forming gas. At mid-flight, two types of composite particles were detected : the first case corresponded to well molten particles where all the alumina shell has flowed to the tail of the particle ; the second case was related to particles which still retained some evidence of the alumina shell uniformly distributed around the stainless steel core. When the mechanofused particles were sprayed onto a cold smooth substrate (stainless steel 316L, Ra<0.05 µm), the resulting splats were extensively fingered and became disk shaped when the substrate surface was preheated over 300°C. However, alumina was either spread exactly on the stainless steel splat corresponding to well molten particles or dispersed in fingers and frozen over the surface of the stainless steel splat corresponding to particles covered by the broken alumina shell. An important effect of fine particle size on in-flight droplet behavior is detected because the center of gravity is more decentred than that of coarse particles influencing the deposit build-up. The composite stainless steel/alumina coatings sprayed on a rough stainless steel substrate (Ra = 6.7 ± 0.3 µm) preheated to 200 °C are compared to those of pure stainless steel. Hardness and adhesion/cohesion of deposits formed with fine particles were found to be improved comparatively to a pure stainless steel deposit. However, when coarse particles are used, the value of hardness is decreased and works is in progress to understand this phenomenon.
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Jonkman, Hayley, Miary Harimanana Andrianarivo, Lauren Bergeron, Moses Jatta, and Madeline S. Marshall. "STRATIGRAPHY OF SHELL BEDS FROM HIGH-SEDIMENT, HIGH-PRODUCTIVITY DEPOSITS OF THE LATE JURASSIC ILONA RIVER, MORONDAVA BASIN, WESTERN MADAGASCAR." In GSA Connects 2022 meeting in Denver, Colorado. Geological Society of America, 2022. http://dx.doi.org/10.1130/abs/2022am-381069.

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Sandquist, Gary M., Jay F. Kunze, and Vern C. Rogers. "Oil Recovery From Shale With Nuclear Generated Heat." In 16th International Conference on Nuclear Engineering. ASMEDC, 2008. http://dx.doi.org/10.1115/icone16-48188.

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Shell Oil Corporation has developed an in-situ process for shale oil recovery that uses electric heaters to heat oil shale deposits and produce chemical reactions within the shale that can liberate the shale-oil. The major production expense is electrical power used to heat the shale. Significantly, small mobile nuclear reactors are now under development and testing that could provide high-temperature working fluids (both gaseous and liquid) at lower unit energy cost to replace current electrical heating. Nuclear generated steam is particularly cost effective and technically attractive for oil shale recovery. Estimates are that US oil shale deposits could be made to produce about 2 million barrels of oil per acre ($200 million/acre of oil at $100/barrel) if properly processed using high temperature steam. Furthermore, a these small nuclear reactors could be delivered by heavy haul truck, carefully buried for adequate shielding and safety, remotely operated, and moved as needed to process large oil shale fields.
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Burchell, Meghan, Anna Sparrow, Marisa Dusseault, Nadine Hallmann, and Bernd R. Schöne. "THE MID-HOLOCENE LANDSCAPE OF DEEP BAY: A MULTI-PROXY APPROACH TO PALAEOENVIRONMENTAL RECONSTRUCTION FROM SHELL MIDDEN DEPOSITS IN COASTAL BRITISH COLUMBIA, CANADA." In GSA Annual Meeting in Indianapolis, Indiana, USA - 2018. Geological Society of America, 2018. http://dx.doi.org/10.1130/abs/2018am-318871.

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Plodinec, M. John, Ping-Rey Jang, Zhiling Long, David L. Monts, Walter P. Okhuysen, Thomas Philip, and Yi Su. "Application of Optical and Imaging Techniques to Inspection of Off-Line Joule-Heated Melter at the West Valley Demonstration Project." In ASME 2003 9th International Conference on Radioactive Waste Management and Environmental Remediation. ASMEDC, 2003. http://dx.doi.org/10.1115/icem2003-4580.

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The West Valley melter has been taken out of service. Its design is the direct ancestor of the current melter design for the Hanford Waste Treatment Plant. Over its eight years of service, the West Valley melter has endured many of the same challenges that the Hanford melters will encounter with feeds that are similar to many of the Hanford double shell tank wastes. Thus, inspection of the West Valley melter prior to its disposal could provide valuable — even crucial — information to the designers of the melters to be used at the Hanford Site, particularly if quantitative information can be obtained. The objective of Mississippi State University’s Diagnostic Instrumentation and Analysis Laboratory’s (DIAL) efforts is to develop, fabricate, and deploy inspection tools for the West Valley melter that will (i.) be remotely operable in the West Valley process cell; (ii.) provide quantitative information on melter refractory wear and deposits on the refractory; and (iii.) indicate areas of heterogeneity of deposits, requiring more detailed characterization. A collaborative arrangement has been established with the West Valley Demonstration Project (WVDP) to inspect their melter.
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de Vries, Guus, Joop van der Meer, Harald Brennodden, and Stein Wendel. "Ormen Lange Gas Field, Immediate Settlement of Offshore Rock Supports." In ASME 2007 26th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2007. http://dx.doi.org/10.1115/omae2007-29038.

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Located approximately 120 km offshore, Ormen Lange, with an estimated 400 billion m3 of natural gas, is the second-largest gas discovery on the Norwegian shelf. The water depth is up to 850 meters, making Ormen Lange the first deepwater project on the Norwegian Continental Shelf. The development of Ormen Lange is under shared operatorship between Norsk Hydro and Shell. Ormen Lange’s untreated well stream will be transported to shore in two 120 km long, 30-inch diameter pipelines to a processing plant at Nyhamna, Norway. From there, gas will be exported via a 42” 1200 km sub sea pipeline (Langeled) to Easington at the east coast of the UK. The pipelines have to pass over the Storegga slide edge which rises 200–300 meters toward the continental shelf in very steep slopes, which are also encountered in the nearshore Bjo¨rnsundet area. The uneven and steep seabed conditions require the use of approximately 2.8 million tons of rock to support and stabilize the pipelines. The sea bottom conditions on the Norwegian continental shelf are characterized by many outcrops as well as very soft clay deposits. The immediate settlement of the rock supports during installation form a significant amount of the total required rock volume. In this paper a procedure is presented on how to assess these immediate settlements recognizing four contributing components all being discussed separately. The calculation results are compared to a back-analysis, performed during the execution of the Ormen Lange rockworks, proving the suitability of the calculation method.
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Hwang, Kyeong Mo, and Tae Eun Jin. "Development and Application of a Plugging Margin Evaluation Method Taking Into Account the Fouling of Shell-and-Tube Heat Exchangers." In ASME 2005 Pressure Vessels and Piping Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/pvp2005-71289.

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As the operating time of heat exchangers progresses, fouling caused by water-borne deposits and the number of plugged tubes increase and thermal performance decreases. Both fouling and tube plugging are known to interfere with normal flow characteristics and to reduce thermal efficiencies of heat exchangers. The heat exchangers of Korean nuclear power plants have been analyzed in terms of heat transfer rate and overall heat transfer coefficient as a means of heat exchanger management. Except for fouling resulting from the operation of heat exchangers, all the tubes of heat exchangers have been replaced when the number of plugged tubes exceeded the plugging criteria based on design performance sheet. This paper describes a plugging margin evaluation method taking into account the fouling of shell-and-tube heat exchangers. The method can evaluate thermal performance, estimate future fouling variation, and consider current fouling level in the calculation of plugging margin. To identify the effectiveness of the developed method, fouling and plugging margin evaluations were performed at a component cooling heat exchanger in a Korean nuclear power plant.
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Banerjee, Sayoni, Kalyan Halder, and Sreetama Aich. "ANALYSIS OF MOLLUSCAN SHELL BEDS FROM LOWER EOCENE DEPOSITS OF CAMBAY BASIN, WESTERN INDIA REVEALS PROLIFERATION OF OPPORTUNIST TAXA IN THE COASTAL SHELTERED ENVIRONMENT IN RESPONSE TO TRANSGRESSIONS." In GSA Annual Meeting in Phoenix, Arizona, USA - 2019. Geological Society of America, 2019. http://dx.doi.org/10.1130/abs/2019am-336447.

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Reports on the topic "Shell deposits"

1

Chriscoe, Mackenzie, Rowan Lockwood, Justin Tweet, and Vincent Santucci. Colonial National Historical Park: Paleontological resource inventory (public version). National Park Service, February 2022. http://dx.doi.org/10.36967/nrr-2291851.

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Colonial National Historical Park (COLO) in eastern Virginia was established for its historical significance, but significant paleontological resources are also found within its boundaries. The bluffs around Yorktown are composed of sedimentary rocks and deposits of the Yorktown Formation, a marine unit deposited approximately 4.9 to 2.8 million years ago. When the Yorktown Formation was being deposited, the shallow seas were populated by many species of invertebrates, vertebrates, and micro-organisms which have left body fossils and trace fossils behind. Corals, bryozoans, bivalves, gastropods, scaphopods, worms, crabs, ostracodes, echinoids, sharks, bony fishes, whales, and others were abundant. People have long known about the fossils of the Yorktown area. Beginning in the British colonial era, fossiliferous deposits were used to make lime and construct roads, while more consolidated intervals furnished building stone. Large shells were used as plates and dippers. Collection of specimens for study began in the late 17th century, before they were even recognized as fossils. The oldest image of a fossil from North America is of a typical Yorktown Formation shell now known as Chesapecten jeffersonius, probably collected from the Yorktown area and very likely from within what is now COLO. Fossil shells were observed by participants of the 1781 siege of Yorktown, and the landmark known as “Cornwallis Cave” is carved into rock made of shell fragments. Scientific description of Yorktown Formation fossils began in the early 19th century. At least 25 fossil species have been named from specimens known to have been discovered within COLO boundaries, and at least another 96 have been named from specimens potentially discovered within COLO, but with insufficient locality information to be certain. At least a dozen external repositories and probably many more have fossils collected from lands now within COLO, but again limited locality information makes it difficult to be sure. This paleontological resource inventory is the first of its kind for Colonial National Historical Park (COLO). Although COLO fossils have been studied as part of the Northeast Coastal Barrier Network (NCBN; Tweet et al. 2014) and, to a lesser extent, as part of a thematic inventory of caves (Santucci et al. 2001), the park had not received a comprehensive paleontological inventory before this report. This inventory allows for a deeper understanding of the park’s paleontological resources and compiles information from historical papers as well as recently completed field work. In summer 2020, researchers went into the field and collected eight bulk samples from three different localities within COLO. These samples will be added to COLO’s museum collections, making their overall collection more robust. In the future, these samples may be used for educational purposes, both for the general public and for employees of the park.
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Field, Michael E., James V. Gardner, David B. Prior, and Glenn Spinelli. Recognition of Diagnostic Acoustic Signatures in Shelf and Slope Deposits: The STRATAFORM California Site. Fort Belvoir, VA: Defense Technical Information Center, September 1999. http://dx.doi.org/10.21236/ada630764.

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Field, Mike, J. C. Moore, and Dan Orange. Understanding the Formation of Strata: Nesting Geophysical Data Sets for Interpretation of Key Stratigraphic Horizons in Shelf and Slope Deposits. Fort Belvoir, VA: Defense Technical Information Center, August 2001. http://dx.doi.org/10.21236/ada625847.

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EVIDENT TECHNOLOGIES TROY NY. High Performance Thermoelectric Materials Using Solution Phase Synthesis of Narrow Bandgap Core/Shell Quantum Dots Deposited Into Colloidal Crystal Thin Films. Fort Belvoir, VA: Defense Technical Information Center, June 2005. http://dx.doi.org/10.21236/ada434970.

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5

Katzir, Nurit, James Giovannoni, and Joseph Burger. Genomic approach to the improvement of fruit quality in melon (Cucumis melo) and related cucurbit crops. United States Department of Agriculture, June 2006. http://dx.doi.org/10.32747/2006.7587224.bard.

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Fruit quality is determined by numerous genetic traits that affect taste, aroma, texture, pigmentation, nutritional value and duration of shelf-life. The molecular basis of many of these important traits is poorly understood and it’s understanding offers an excellent opportunity for adding value to agricultural products. Improvement of melon fruit quality was the primary goal of the project. The original objectives of the project were: The isolation of a minimum of 1000 fruit specific ESTs. The development of a microarray of melon fruit ESTs. The analysis of gene expression in melon using melon and tomato fruit enriched microarrays. A comprehensive study of fruit gene expression of the major cucurbit crops. In our current project we have focused on the development of genomics tools for the enhancement of melon research with an emphasis on fruit, specifically the first public melon EST collection. We have also developed a database to relay this information to the research community and developed a publicly available microarray. The release of this information was one of the catalysts for the establishment of the International Cucurbit Genomic Initiative (ICuGI, Barcelona, Spain, July 2005) aimed at collecting and generating up to 100,000 melon EST sequences in 2006, leveraging a significant expansion of melon genomic resources. A total of 1000 ESTs were promised under the original proposal (Objective 1). Non-subtracted mature fruit and young fruit flesh of a climacteric variety in addition to a non-climacteric variety resulted in the majority of additional EST sequences for a total of 4800 attempted reads. 3731 high quality sequences from independent ESTs were assembled, representing 2,467 melon unigenes (1,873 singletons, 594 contigs). In comparison, as of June 2004, a total of 170 melon mRNA sequences had been deposited in GENBANK. The current project has thus resulted in nearly five- fold the number of ESTs promised and ca. 15-fold increase in the depth of publicly available melon gene sequences. All of these sequences have been deposited in GENBANK and are also available and searchable via multiple approaches in the public database (http://melon.bti.cornell.edu). Our database was selected as the central location for presentation of public melon EST data of the International Cucurbit Genomic Initiative. With the available unigenes we recently constructed a microarray, which was successfully applied in hybridizations (planned public release by August 2006). Current gene expression analyses focus on fruit development and on comparative studies between climacteric and non-climacteric melons. Earlier, expression profiling was conducted using macroarrays developed at the preliminary stage of the project. This analysis replaced the study of tomato microarray following the recommendations of the reviewers and the panel of the original project. Comparative study between melon and other cucurbit crops have begun, mainly with watermelon, in collaboration with Dr. Amnon Levi (USDA-ARS). In conclusion, all four objectives have been addressed and achieved. In the continuation project that have been approved we plan to apply the genomic tools developed here to achieve detailed functional analyses of genes associated with major metabolic pathway.
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King, E. L., A. Normandeau, T. Carson, P. Fraser, C. Staniforth, A. Limoges, B. MacDonald, F. J. Murrillo-Perez, and N. Van Nieuwenhove. Pockmarks, a paleo fluid efflux event, glacial meltwater channels, sponge colonies, and trawling impacts in Emerald Basin, Scotian Shelf: autonomous underwater vehicle surveys, William Kennedy 2022011 cruise report. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/331174.

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A short but productive cruise aboard RV William Kennedy tested various new field equipment near Halifax (port of departure and return) but also in areas that could also benefit science understanding. The GSC-A Gavia Autonomous Underwater Vehicle equipped with bathymetric, sidescan and sub-bottom profiler was successfully deployed for the first time on Scotian Shelf science targets. It surveyed three small areas: two across known benthic sponge, Vazella (Russian Hat) within a DFO-directed trawling closure area on the SE flank of Sambro Bank, bordering Emerald Basin, and one across known pockmarks, eroded cone-shaped depression in soft mud due to fluid efflux. The sponge study sites (~ 150 170 m water depth) were known to lie in an area of till (subglacial diamict) exposure at the seabed. The AUV data identified gravel and cobble-rich seabed, registering individual clasts at 35 cm gridded resolution. A subtle variation in seabed texture is recognized in sidescan images, from cobble-rich on ridge crests and flanks, to limited mud-rich sediment in intervening troughs. Correlation between seabed topography and texture with the (previously collected) Vazella distribution along two transects is not straightforward. However there may be a preference for the sponge in the depressions, some of which have a thin but possibly ephemeral sediment cover. Both sponge study sites depict a hereto unknown morphology, carved in glacial deposits, consisting of a series of discontinuous ridges interpreted to be generated by erosion in multiple, continuous, meandering and cross-cutting channels. The morphology is identical to glacial Nye, or mp;lt;"N-mp;lt;"channels, cut by sub-glacial meltwater. However their scale (10 to 100 times mp;lt;"typicalmp;gt;" N-channels) and the unique eroded medium, (till rather than bedrock), presents a rare or unknown size and medium and suggests a continuum in sub-glacial meltwater channels between much larger tunnel valleys, common to the eastward, and the bedrock forms. A comparison is made with coastal Nova Scotia forms in bedrock. The Emerald Basin AUV site, targeting pockmarks was in ~260 to 270 m water depth and imaged eight large and one small pockmark. The main aim was to investigate possible recent or continuous fluid flux activity in light of ocean acidification or greenhouse gas contribution; most accounts to date suggested inactivity. While a lack of common attributes marking activity is confirmed, creep or rotational flank failure is recognized, as is a depletion of buried diffuse methane immediately below the seabed features. Discovery of a second, buried, pockmark horizon, with smaller but more numerous erosive cones and no spatial correlation to the buried diffuse gas or the seabed pockmarks, indicates a paleo-event of fluid or gas efflux; general timing and possible mechanisms are suggested. The basinal survey also registered numerous otter board trawl marks cutting the surficial mud from past fishing activity. The AUV data present a unique dataset for follow-up quantification of the disturbance. Recent realization that this may play a significant role in ocean acidification on a global scale can benefit from such disturbance quantification. The new pole-mounted sub-bottom profiler collected high quality data, enabling correlation of recently recognized till ridges exposed at the seabed as they become buried across the flank and base of the basin. These, along with the Nye channels, will help reconstruct glacial behavior and flow patterns which to date are only vaguely documented. Several cores provide the potential for stratigraphic dating of key horizons and will augment Holocene environmental history investigations by a Dalhousie University student. In summary, several unique features have been identified, providing sufficient field data for further compilation, analysis and follow-up publications.
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Modeling Cape- and Ridge-Associated Marine Sand Deposits; A Focus on the U.S. Atlantic Continental Shelf. US Geological Survey, 2009. http://dx.doi.org/10.3133/b2209m.

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Mineral Resource Assessment of Marine Sand Resources in Cape- and Ridge-Associated Marine Sand Deposits in Three Tracts, New York and New Jersey, United States Atlantic Continental Shelf. US Geological Survey, 2009. http://dx.doi.org/10.3133/b2209n.

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