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Geology of Wreck Bay, Vancouver IslandBremner, James Michael January 1970 (has links)
Wreck Bay is located on the west coast of Vancouver Island at 49°00'N, I25°38'W. It is roughly crescent shaped with a small cuspate foreland named Sand Point in the middle, and measures 2½ miles (2.17 kilometers) between the enclosing headlands of Quisitis and Wya Points.
Rocks exposed along the coast are indurated, unmetamorphosed, impure sandstones and mudstones of late Jurassic to early Cretaceous age. They were derived from the hinterland northeast of Wreck Bay, and were rapidly deposited into a trough which extended parallel to the present-day coastline. The contact between these sediments and the source rocks is thought to lie beneath a thick cover of Pleistocene material which now overlies the Estevan Coastal Plain; the southwestern edge of the paleotrough, from seismic evidence, appears to lie 5 - 6 miles (4.35 - 5.22 kilometers) seaward from the present-day coastline. Infilling of both sides of this paleotrough with Pleistocene and Recent sediments has resulted in a narrow, arcuate, present-day trough on the continental shelf adjacent to Wreck Bay. The Pleistocene sediments, consisting of cohesive grey clay and glaciofluvial outwash, were also derived from the mountainous hinterland to the northeast, and recent sediments derived therefrom are dispersed across the bay and inner shelf. Boulders and gravel freed from the retrograding sea cliff behind the beach have settled to the base of wave erosion in the bay, and this coarse "mat" is covered by a thin veneer of very well sorted fine sand which becomes progressively finer further away from shore. A nearshore surface current transports clay, silt and some of the sand southeastwards to Wya Point and the offshore trough.
During the summer, breaker heights in the bay vary from 0.75 - 4.00 feet (0.23 - 1.27 meters), and it is calculated that during winter storms, wave heights exceed 19 feet (5.75 meters). The foreshore in summer consists of fine, light-coloured sand, and slopes gently seaward at less than 2.6°. Profile changes on the foreshore result from three controlling factors: the breaker height, the breaker incident angle, and the position of the water table on the beach. The direction of littoral drift near the middle of the beach changes with tide level, but generally it is towards Sand Point and very strong; near Quisitis and Wya Points it is weak, and consistently away from them; elsewhere, it is weak and variable in direction. Transverse profiles were found to be most sensitive to tidal range where the brisker incident angle was small and consistent; they were virtually insensitive where the breaker incident angle was small and variable. In winter, the foreshore is generally less steep than in summer, and near Sand Point the surface material of the beach is reduced to coarse gravel as sand is carried out to the middle of the bay; northwest and southeast from here, the beach surface consists of dark-coloured medium sand; adjacent to the two headlands, the light-coloured fine sand of summer remains. Profile changes in winter are determined by breaker heights only, the other two controlling factors becoming insignificant. Runnels, or incipient beach cusps, tend to form wherever littoral drift is not too strong, and their spacing is apparently related to the thickness of the swash wedge. The cliffbase along the northwest half of Wreck Bay very closely approximates a log-spiral curve in plan due to the angular relationship between prevailing wave fronts and the coastline; the southeast half, however, does not, because a complex wave pattern is created in the lee of islands located in the middle of the bay.
The value of gold contained in the backshore near Lost Shoe Creek is calculated to be $10,650. An offshore placer deposit at 20 fathoms (36,6 meters) depth is indicated by a great increase in the amount of magnetite and other heavy minerals there, together with the fact that a small mode of very fine sand, which contains most of the heavy minerals onshore, reappears in samples collected from this bathymetric level. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
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Hydrocarbons in the open ocean waters near the Galician Bank after the deep sea spill from the Prestige wrecksElordui-Zapatarietxe, Saioa 03 June 2009 (has links)
Hoy en día existe una escasez de estudios sobre la distribución de los hidrocarburos en mar abierto, aunque el aumento de la explotación de yacimientos de petróleo y la intensificación del tráfico marítimo más allá de la plataforma continental haya aumentado. Asimismo, se han identificado nuevas fuentes de contaminación. En los últimos años se ha puesto en evidencia el alto número de barcos hundidos en los fondos marinos que podrían potencialmente generar futuros vertidos de petróleo. En esta tesis, se investiga el accidente del petrolero Prestige cerca de Galicia en el 2002 como caso de estudio de un vertido marino en profundidad en mar abierto, ya que aproximadamente unas 43.000 toneladas de fuel oil pesado que llevaba a bordo fueron vertidas una vez el barco de rompió en dos y se hundió. Además, la zona del hundimiento del Prestige es un área hidrodinámicamente compleja. La columna de agua esta formada por cinco masas de aguas principales, de diferente origen y con características físico-químicas diferentes, que pueden contribuir activamente extender el fuel liberado por el Prestige en las aguas cerca del Banco de Galicia. En este contexto, el principal objetivo de la presente tesis ha sido determinar la importancia de los pecios del Prestige como fuente de contaminación en las aguas cerca del Banco de Galicia varios años después del accidente e investigar el papel de las masas de agua en el transporte y distribución de los hidrocarburos en la zona del hundimiento. Estos objetivos se han alcanzado mediante la combinación de estudios de laboratorio y trabajo de campo. Por un lado, se realizaron diferentes experimentos bajo condiciones estables de temperatura y salinidad que dieron información sobre la disolución potencial del fuel del Prestige en agua marina. Además, dos campañas oceanográficas se llevaros a cabo en marzo y octubre del 2006 cerca de los pecios y las zonas adyacentes, con el objetivo de recoger agua marina. Se determinaron hidrocarburos en la materia sólida en suspensión y la fase disuelta del agua en la columna de agua de las tres estaciones. Una se encontraba encima de los pecios del Prestige mientras que las otras dos se localizaron a 73 millas náuticas, una al norte y la otra al sur de este punto. En marzo del 2006, en la zona del hundimiento y en las otras dos estaciones, las concentraciones de hidrocarburos de origen petrogénico estaban dentro el rango los niveles descritos en la literatura para áreas similares, mientras que los niveles en octubre del mismo año era superiores. Las concentraciones de hidrocarburos poliaromáticos encontrados en la fase disuelta eran, tanto en marzo como en octubre, mucho mayores que los niveles de referencia establecidos para la zona. La huella química de los hidrocarburos en octubre del 2006 indicó que los pecios del Prestige habían estado liberando fuel oil durante varios años después del accidente. Sin embargo, a pesar de la amplia presencia de hidrocarburos provenientes del petróleo en la columna de agua de las tres estaciones, no se puede afirmar que el Prestige constituía la fuente más importante de contaminación en le área, ya que los hidrocarburos parecían provenir de múltiples orígenes. De hecho, varias masas de agua presentan contenidos distintivos de hidrocarburos en la fase disuelta y material particulado. El estudio realizado se puede entender como un ejemplo del potencial de un pecio hundido en el Noratlántico profundo como fuente de contaminación. Aunque cada pecio representa un caso único, el conocimiento obtenido sobre la distribución espacial y temporal de los hidrocarburos después del accidente del Prestige se puede utilizar en futuros vertidos. / There is an apparent shortage of studies on the distribution and fate of oil hydrocarbons in open ocean waters. Nevertheless, given the increasing exploitation of oilfields in the high seas, and the intensification of maritime traffic, in the last decades, oil pollution of the marine environment beyond the continental platforms is increasing. In addition, new sources of pollution are being recognized. Thus, in recent years it has been noted that the high number of sunken vessels scattered in the oceans sea floor are potentially a present and future source of oil spills. In this thesis, the accident of the Prestige tanker in 2002 off the Galician coast is investigated as a case study of a deep sea spill in open ocean waters, since around 43,000 tonnes of heavy fuel oil were spilled after the vessel broke in two and sank. In addition, the area near the Galician Bank, where the Prestige wrecks are located, is hydrodynamically complex. The water column is comprised by five main water masses from different origins and physico-chemical properties, which may contribute to actively spread the oil released from the Prestige in different and distinct ways. In this context, the main aim of this study has been to determine the importance of the Prestige shipwrecks as a source of oil pollution in the waters near the Galician Bank several years after the accident took place and to investigate the role of the water masses in the sinking area in the transport and distribution of hydrocarbons. These objectives have been tackled by a combination of laboratory and field studies. First of all, several sets of experiments were carried out under controlled temperature and salinity conditions which provided information about the potential dissolution of the Prestige fuel oil in seawater. In addition, two oceanographic cruises were undertaken in March and October 2006, near the wrecks location and surrounding areas, to collect seawater samples. Hydrocarbons were determined in the suspended particulate matter (SPM) and dissolved phase (DP) in the water column of three stations. One was located above the Prestige wrecks, and the other two 73 nautical miles north and south of the Prestige incident area.Hydrocarbons concentrations from petrogenic sources in the SPM above the wreck and surrounding areas in March 2006 were within the range of abundances previously reported for similar areas, but much higher in October 2006. The concentrations of polycyclic aromatic hydrocarbons found in the DP were, both in March and October 2006, well above any expected background levels. The chemical fingerprint of the hydrocarbons indicated that in October 2006 the oil at the Prestige station originated from the wrecks. This, together with the unusually high relative concentration of hydrocarbons in the DP at the Prestige station in March 2006, indicates that the Prestige wrecks had been releasing oil for several years after the accident. However, despite the widespread occurrence of oil hydrocarbons in the three stations and throughout their water columns, it could not be concluded that the Prestige was the main source of pollution in the area near the Galician bank, which most likely has multiple origins. In fact, different water masses contain distinct contents of hydrocarbons in the SPM and the DP, which in some instances may have remote sources. The study conducted can be viewed as an example of the potential of a sunken wreck in the deep North Atlantic as a source of pollution. Although each potentially polluting shipwreck represents a singular case, knowledge obtained about the temporal and spatial distribution of hydrocarbons after the accident of the Prestige could be applied to deal with other deep spills in the future.
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Impacts of Bottom Trawling on Underwater Cultural HeritageAtkinson, Christopher 2012 May 1900 (has links)
The fishing method of trawling, or dragging, has long been shown to be harmful to a plethora of sea life inhabiting the world?s oceans and inland waterways. Fishing nets scour the seabed, disturbing everything in their path, while usually in search of only one type of bottom-dwelling species. Impacts to the seafloor include a removal of topographic features, disturbance of the upper sediment layers, including deep furrows, as well as physical and chemical changes to sediment morphology. While biological organisms and communities can potentially recover from this destruction, archaeological data cannot. Fishermen have been raising important artifacts in their nets for over a century. These finds have helped archaeologists locate significant sites, but they also have the adverse effect of irreparably damaging these sites. This thesis explores the impacts of bottom trawling on underwater cultural heritage. The methods and gear used by trawlers and their documented effects upon the sea floor are identified. Examples of the types of damage shipwreck sites receive after being impacted by trawling are presented. Instances where fishermen have raised prehistoric artifacts from inundated land sites are also introduced. The fishing and archaeological communities must cooperate to limit further damage to underwater cultural heritage around the globe.
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Sand sources, volumes and movement patterns on Wreck Beach, Vancouver, British ColumbiaPool, Meridith Ines January 1975 (has links)
Along Wreck Beach the existing headland cliffs are eroding
and receding under attack from terrestrial and marine agents.
Valuable property is being lost and nearby structures endangered.
Remedial measures were undertaken in the summer of 1974
to halt wave erosion along the cliff base. A rock groin and
sand—gravel protective beach scheme was only partially success
ful during the following year. To design an adequate protection
system for the cliffs wind and wave effects need to be deter
mined to fully understand the resulting sand movement patterns.
Understanding the processes affecting Wreck Beach is the first
step in controlling them.
Methods used to investigate sand movement included field
coverage of the study area in photographic form as well as
instrument cross—sectioning over a two year period. These data
were correlated with historical wind records and predictions
from wave refraction diagrams to determine seasonal movement
onto and off the beach face and the cyclic progression of
sandbars in the longshore current direction. Annual sand trans
port volumes, sand supply sources and amounts contributed are
outlined.
In designing a protection scheme in which longshore trans
port requirements must be considered the information and calcu
lations suggests that the Fraser River North Arm could amply
provide the longshore transport supply requirements. However,
some means in addition to the present natural processes must
be available to bring this sand into a range where wind gen
erated wave activity can incorporate it into the existing
Wreck Beach system. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
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Western Empire: the deep water wreck of a mid-nineteenth century wooden sailing shipLevin, Joshua Aaron 16 August 2006 (has links)
This study of Western Empire is split into two distinct parts: (1) historical research of the
life of the vessel, relying on primary documents; and (2) analysis of the deep water
survey data. The first part concentrates on the historical documents that constitute the
history of Western Empire. The second part begins with a review of the tools and
procedures used in performing the deep water survey. An analysis of the information
that can be taken from such a study will follow, and it concludes with suggestions for
remotely operated vehicle operators when performing an on-the-fly survey of
shipwrecks in deep water. The official ship logs, crew agreements, and contemporary
newspaper articles are used to recreate the life of Western Empire and shed light on a
period in which wooden sailing ships were being displaced by iron ships and steam
power.
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Watershed modeling using HEC-RAS, HEC-HMS, and GIS models a case study of the Wreck Pond Brook Watershed in Monmouth County, New Jersey /Patel, Kunal P., January 2009 (has links)
Thesis (Ph. D.)--Rutgers University, 2009. / "Graduate Program in Civil and Environmental Engineering." Includes bibliographical references (p. 259-263).
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Skeppsteknik : en studie om teknikutveckling hos skepp i Medelhavet / Ship technology : a study about the technical development of ships in the MediterraneanSokulu, Sila January 2010 (has links)
<p>Techniques used in the building of a number of ships from the Mediterranean will be presented in this paper. The two techniques thnat will be discussed are shell-based technique and skeleton-basedtechnique. An attempt to clearify and delineate the transition between these two techniques will be made. The possible reasons for transition will then be described and discussed. The development ofthe techniques is going to be identified with help from four wrecks by analyzing their edge joineriesand this facts will be used as a basis for a chronological presentation. Finally, data from theanalyzed wrecks will be compared and the results are interpreted in the text.</p>
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Vardagslivet i hamnen : Djurhamns historia belyst med marinarkeologiskt materialWiklund, Jonas January 2015 (has links)
Those who today hear the name Djurhamn are maybe first thinking of a summer resort place with sunbathing, swimming and recreational boating activities. Djurhamn has an interesting and fascinating history well intertwined with the history of Sweden. The interesting history was exposed by the Stockholm Sport Diving Club which, during the summers of 1964 and 1965, brought up a large number of finds from the bottom of Djurhamn. The findings could essentially be dated to be in the in the period 1500s to 1700s. Like other parts of the East Coast Djurhamn was hit in "Russian raids" in the early 1700s. The known meetings of warships during the Vasa era and the history of naval ship Riskswasas fate also reflects the interesting parts of Djurhamn history. While working on this, a number of dives were made at the bottom of the basin in Djurhamn. Two side-scan surveys have also been conducted. Overall, this has not resulted in any change of the picture of what's on Djurhamns bottom. A previously unknown wreck that lies south of the cemetery have, however, been located based on information from the public. The finds from the dives during 1964 and 1965 talk about food and drinks, cooking utensils, three-leg pots and bottles speaks their language. Even earlier dated bargain materials speak the same language. It is a place where everyday objects leave imprints on the bottom along with the testimony of a brickyard, which flourished for a short period. Which traces have been left from the naval activities? Practically none. On land there are no naval monuments. The objects which were brought up at the 1960 dives were almost entirely attributable to the applications connected to cooking. Our modern society is a complex reality. There are homes, workplaces, hospitals, places of entertainment, etc. People are born, grow up, grow old and die. What do we find in the signs of the Djurhamn? Well, a picture that much is a reflection of today's society. Also here you are born grown up grown old and finally dead. Heavy drinking has flourished. In addition to self-household and shipping, there has been brick industry and cholera quarantine. Finally, perhaps Djurhamn over time is best described as farmers, fishermen and hungry sailors’ history more than the history of the fleet in the Vasa kings’ service.
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Skeppsteknik : en studie om teknikutveckling hos skepp i Medelhavet / Ship technology : a study about the technical development of ships in the MediterraneanSokulu, Sila January 2010 (has links)
Techniques used in the building of a number of ships from the Mediterranean will be presented in this paper. The two techniques thnat will be discussed are shell-based technique and skeleton-basedtechnique. An attempt to clearify and delineate the transition between these two techniques will be made. The possible reasons for transition will then be described and discussed. The development ofthe techniques is going to be identified with help from four wrecks by analyzing their edge joineriesand this facts will be used as a basis for a chronological presentation. Finally, data from theanalyzed wrecks will be compared and the results are interpreted in the text.
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Nakládání s autovrakyHAJNÝ, Vladislav January 2018 (has links)
Works on Car Wrecking deals with the possibilities of environmentally friendly disposal or recycling of individual parts of a passenger car. The aim of this diploma thesis is to describe the possibilities of liquidation or recycling of individual car parts made from different materials, to describe the necessary duty of the given vehicle during permanent decommissioning of the traffic inspectorate, to carry out the practical liquidation of the selected car wreck, to describe the procedure of dismantling the car wreck and to express weight its individual parts. I believe that I will acquire other valuable theoretical and practical knowledge, which I will apply in the technical practice.
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