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Sjöherravälde : är Corbetts teorier applicerbara på modern ubåtskrigföring?Blomqvist, Edith January 2009 (has links)
Sjöherravälde, Corbetts teorier inom ramen för modern ubåtskrigföring. Studie om Corbetts teorier och hur de appliceras på modern ubåtskrigföring. Sjökrigets grunder beskrivs inledningsvis samt av Corbett sammanställda metoderna för etablerande, bestridande samt utövande av sjöherravälde och ubåten som vapen. Därefter följer en studie av historiska källor rörande modern ubåtskrigföring. I denna ingår Scapa Flow 1939, ubåtsstrid vid slaget om Atlanten och USAs sjöfartskrig mot Japan samt sänkningen av Belgrano och det inledande skedet av Falklandskriget 1982. Fokus ligger på de olika metoderna som Corbett beskriver för sjöherravälde: avgörande slag, blockad, fleet in being, försvar mot landstigning, sjöfartskrig, amfibieoperationer samt stödjande av expeditionsstyrkor. Med bakgrund i dessa utmynnar uppsatsen i en diskussion om modern ubåtskrigföring som i stor utsträckning verifierar Corbetts teorier. / Naval supremacy, Corbett’s theories within the framework of modern submarine warfare? Study of Corbett’s theories and how they apply on modern submarine warfare. Basics of naval warfare is initially described as well as by Corbett complied methods for establishing, disputing and practising naval supremacy and also the submarine as a weapon. Subsequently follows a study of historical sources of modern submarine warfare. This includes Scapa Flow 1939, submarine warfare at the battle of the Atlantic sea and the United States attack on Japanese sea trade in addition to the attack on Belgrano and the preliminary of the Falkland war. Focus is on the different methods for naval supremacy that Corbett describes: naval battle, blockade, fleet in being, minor counterattacks, defence against invasion, attack and defence on trade as well as attack, defence and support of military expeditions. With these in context the study results in a discussion about modern submarine warfare that in large extent verifies Corbett’s theories.
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Early Channel Evolution in the Middle Permian Brushy Canyon Formation, West Texas, USAGunderson, Spencer 2011 August 1900 (has links)
Submarine channels are important conduits for sediment in deep marine environments, and understanding their formation is critical to modeling basin fill processes. Most models describing channel evolution focus on turbidity currents as the erosive and constructive force in channel initiation. However, slope failure and slumping can be significant drivers of channelization, particularly in upper slope and ramp environments. Determining the relative roles of slumping and erosion by turbidity currents can provide important insight into the timing of channelization and the geometries of subsequent deposits. Samples were collected from Guadalupe Mountains National Park from two primary localities at Salt Flat Bench (Figure 2). Three vertical sections were measured at both locations. A total of 16 samples were collected for petrographic analysis and X-ray fluorescence (XRF) imaging.
Spectacular outcrop quality makes the Middle Permian Brushy Canyon Formation in Guadalupe Mountains National Park an ideal location for the study of early channel evolution. A detailed facies analysis of fine-grained channel deposits was conducted in the Upper Brushy Canyon Formation in the Salt Flat Bench outcrops. After channelization, an interval of relative condensation dominated by hemipelagic settling of organic matter and silt was followed by an interval of incomplete sediment bypass by turbidity currents. This sequence of events suggests that sea level was at a relative highstand at the time of channel inception, whereas channel inception by turbidity currents is expected during a lowstand. Slumping rather than erosion by turbidity currents is the most likely mechanism to have initiated a channel at the study area. There is no evidence for the existence for high energy currents until after the interval of condensation. However, the action of weak contour currents during early channel evolution is observed in outcrop and microtextural features. Early carbonate cementation of channel-lining silts may have stabilized the slump surface with respect to erosion by later turbidity currents.
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Living (Rose Bengal Stained) Benthic Foraminifera in Sediments off the Southwest TaiwanChiang, Ai-Ping 24 August 2004 (has links)
The objective for this study was to provide the insight into the link between benthic foraminiferal assemblages and the surrounding environment. Stained sediment samples were collected from the continental shelf and slope off the southwest Taiwan, including the Kao-ping Submarine Canyon. In addition to faunal census, total organic carbon (TOC), carbonate, and coarse fraction of the sediments were also measured. Nevertheless, the downcore record of the excess 210Pb from selected sites offers the constraint for stratigraphy time frame for discussion.
The benthic foraminiferal assemblages were analyzed by statistics. Clusters analysis shows that all species present in this study could be divided into two groupings. One is those distributed in outer shelf and the other is those found in the inner shelf of the southwest Taiwan. Different from previous studies, the spatial distribution of stained benthic foraminifera seems not to be related with TOC contents in the sediment and water depth. Both the diversity index and Eqitability show that sites inside of the canyon have lower values. The higher Living/Total ratios and lower dead tests at the head of Kao-ping Submarine Canyon than adjacent area might be the effect of migration. Furthermore, the species within the canyon are similar to the southern and northern continental shelf. These findings indicate that the spatial distribution of benthic forams within canyon might be the effect of transport, which could result from the complex interaction between tides and currents.
Augmented with the profiles of excess 210Pb, the temporal variation of benthic foraminifera was revealed. Generally there is a progressive decrease in the abundance of Ammonia sp.. It is possible that the diminishing trend was caused by the increase of anthropogenic activity for the last 30 years.
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The Study of Flow Dynamics in Kao-ping Submarine Canyon and near Kao-ping ShelfWu, Meng-lin 27 August 2004 (has links)
The interaction between the submarine canyon topography and coastal current has very important influence on the flow field around the canyon. This study aims to understand the nature of the interaction and the associated dynamic around the Kao-ping Submarine Canyon in southern Taiwan. In 2000 and 2002 year during the flood season of the Kao-ping River, moored instruments were deployed in the Kao-ping Submarine Canyon, Kao-ping River mouth, and Kao-ping shelf for one month. The results revealed sea surface fluctuations were dominated by the tide. The sea surface fluctuations at Kao-ping River mouth and Liu-Chiu Yu Island belong to mixed tide with diurnal dominance. But the sea surface fluctuations on the shelf belong to mixed tide is having by semi-diurnal dominance. The current fields of the shelf and canyon both are dominated by semi-diurnal tide. The energy of tidal current is stronger with increasing canyon depths. Results of harmonic analysis show that the current field of canyon bottom layer and on the shelf both is dominated by the M2 component. The variation of temperature field is regulated by tidal currents. During floods, shelf flow is northwestward and the current of canyon bottom layer flow downcanyon. During ebbs, shelf flow is southeastward and the current of canyon bottom layer flow upcanyon. The interaction between the temperature field of submarine canyon and shelf is pronounced. The tidal fluctuation of temperature field on shelf is especially conspicuous during spring tide. When temperature decreases in the submarine canyon, the shelf temperature begins to decline. When temperature increases in the submarine canyon, the shelf temperature begins to arise. The results of harmonic analysis reveal that the temperature field of the canyon leads that of the shelf around 2.08 hours. The current field of bottom layer in the canyon flows towards the canyon head during ebb tides. It brings the colder and deeper water to canyon head along the canyon axis. The colder and deeper water causes the water temperature to decrease in the canyon and on the shelf. During flood tides, the colder and deeper water withdraw from the canyon head region, which makes the shelf temperature increase.
The currents on the Kao-ping shelf both are largely alongshore in 2000 and 2002 observations. The alongshore mean current is northwestward. The current velocity of surface layer is greater than that of the bottom layer. In Kao-ping Submarine Canyon, the mean current of bottom layer at 195m and 245m flows in opposite directions. It flows downcanyon offshore at 195m and upcanyon at 245m. The current velocity of 245m is greater than 195m. Mean current flow of bottom layer is downcanyon along canyon axis at 280m in 2002 year. During the transition between ebb tide and flood tide, temperature fields of canyon and shelf show trend reversal. Submarine canyons play an important role in transport deeper and colder water. The interaction of canyon and shelf current field can influence the variation of shelf temperature. The tidal current velocity is stronger in spring tide. It is easier to make deeper and colder water to ascend to the shelf. The influence of current is more noticeable to adjust on the shelf and canyon temperature fields during the spring tide. The results of scale analysis show the canyon topography can influence coastal current when the radius deformation of the canyon is smaller than the canyon width. The canyon current will produce phenomena of upwelling and down-welling with tidal periods. This seems match Klink¡¦s¡]1996¡^model results.
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Inferred Suspended Sediment Transport Process in the Head Region of Kao-Ping Submarine Canyon Based on Temporal and Spacial Hydrographic ObservationsHuang, Jeffery 12 July 2002 (has links)
Kao-ping submarine canyon is straightly connected with Kao-ping River. Thus, it is influenced by the river¡¦s discharge. In order to investigate this seasonal difference in the canyon, we conducted several researches, which were based on temporal and spacial observations of the hydrological and dynamical characteristic of the canyon. We also studied the transport of suspended sediment particles in the canyon according to the distribution of SSC (suspended sediment concentration). In our research, we made along-canyon profile observations. We collected data by using CTD, ADCP and Transmissometer on R/V Ocean Researches Vessel ¢». The data include flood season cruises (CR536, CR248, CR552, CR634 and CR639), and dry season cruises (CR572, CR598, CR608).
Based on the temporal and spacial observations, in June and July 1999 we found a cold pool at the location where canyon topography changed sharply. We also found the density disturbance and high concentration at the same location. When the tidal current was landward in the deep canyon, we can observes upwelling in the head region of the canyon. Conversely, we can observe downwelling while the tidal current was seaward. Moreover, we observed a strong vertical flow in the dry season, which can make resuspended easily.
Besides, we deployed an instrument covey, including sediment traps, Recording Current Meter (RCM), wave gauge (S700) and Laser In-Suit Scattering and Transmissiometry (LISST-100), at the location where we previously observed SSC localizes high for one month (from June to July 2000) to investigate the temporal relations among temperature, salinity, flow, and suspended particles. From this time series observation we found a coincidence between cold temperature signal and the northward flow. It showed that the cold water from deep sea was transported to the head region of the canyon by a ¡¥Pump¡¦ process. We also observed the suspended particles at the top (195m), middle (245m), and the bottom (285m) of the ocean. According to their different sizes, we found that the upper depth has more sands which were from the continental shelf, and the middle and lower depth have more silt and clay.
Subsequently, we used Empirical Orthogonal Function (EOF) analysis to explain the relationship among hydrological and flow factors of the canyon. We concluded that two major modes to explain the observed relationship: Submarine canyon seasonal effect, and dynamic stability.
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Distribution Patterns of Lead-210 and Polonium-210 Along the Gaoping Submarine CanyonShen, Ya-ting 09 September 2008 (has links)
Abstract
The purposes of this study are to understand the variations of the particulate and dissolved 210Pb and 210Po profiles in the water column of Gaoping Submarine Canyon(GSC) and to compare the distributions of the two nuclides in settling particles and sediments. Different types of samples taken in this area were analyzed for 210Pb and 210Po in order to understand processes involved in the particulate transport. Seawater samples were collected from Ocean Researcher III Cruise (ORIII-1192 in Nov, 2006). Sediment trap was deployed on Jun 21, 2000 and recovered on Jul 20, 2000 (ORIII-634). Sediments cores collected from ORIII-642 on Jul 21, 2000 (Core A-B) and ORIII-696 on Apr 7, 2001 (Core D-F) using multicorer.
The profiles of 210Pb and 210Po in water column could be divided into two types one is estuarine and the other is oceanic. The profiles of dissolved nuclides in estuarine stations (CW1 to 3) are lower than in the oceanic stations (CW4-5). Because stations CW1 to 3 are controlled by large amount of terrigenous particles, scavenging in the three stations is quite obvious.
The nuclide activities of the settling particles decrease with depth, probably due to dilution by resuspended surface sediment of lower activities, similar to observations in this study area. The downcore distributions of 210Pb and 210Po show clearly disequilibria between the two nuclides and suggested that sediment deposited in GSC has been disturbed down to 40-50 cm deep. All the data indicate the 210Po in the water column and in the settling particles as well as in the surface sediments is strongly deficient relative to its parent, 210Pb. Using a box-model and considering the influence of horizontal transports, we may calculate the residence times of 210Po in the 100m water layer in the GSC, to be 2.1d for the dissolved phase and 7.0 d for the particulate phase with a total 210Pb residence time is 3.8d.
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Biogenic Particle Transport in the Gaoping Submarine Canyon off Southwestern Taiwan- Comparison of T6KP and T7KP Sediment TrapsLin, Yi-Jiun 04 September 2009 (has links)
Submarine canyons are common features on continental margins worldwide. They are important natural conduits for transfer of terrigenous sediments to the deep sea, and thus, preferential pathways for shelf-slope exchange. The purpose of this study is to understand the biogenic particle transport in the seasons according two sediment trap moorings deployed in the Gaoping submarine canyon. The T6KP mooring was deployed in dry season while the T7KP mooring was deployed in wet season. Two typhoons, Kalmaegi and Fung Wong, invaded Taiwan during 16-18 and 26-29 July within the deployment of T7KP. We discussed the influence of rainfall and river discharge on biogenic particle transport based on results of the two sediment traps. The foraminiferal abundance in sediment traps in comparison with plankton tows was discussed regarding the particle transport mechanism of the water column in the Gaoping submarine canyon.
The biogenic particle transport was a tide-dominated situation and displayed a periodic variation in dry season. In wet season, fine grain fraction (less than 63 micro meter) was dominant in the particle size and sedimentary condition was flood-dominated. The sedimentary condition was back to the tide-dominated state approximately 15 days after Kalmaegi typhoon (16-18, July). The activities of 210Pb and 234Th in the lower trap of T7KP mooring were an order less than that in T6KP mooring, indicating particles scavenge nuclides of the water column less effectively in wet season than in dry season. The absolute abundances of foraminifera in the canyon revealed that the biogenic particle was influenced by the terrigenous input and was different between dry and wet seasons. Seasonal variations of total flux and relative abundance of living foraminifera were evident in the upper 200 m water column near the Gaoping submarine canyon. Therefore, the seasonal variations of living foraminifera might be reflected on the biogenic particle transport in different seasons in the Gaoping submarine canyon.
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Numerical simulation of topography and stratification effects to the internal tide in Gaoping Submarine CanyonLee, Ying-Tsao 10 September 2009 (has links)
It is generally understood that tidal currents ominated the flow field in many submarine canyons, and internal tide may be an order of magnitude more energetic than that of barotropic. The internal tide can be generated and amplified in a marine environment with the strong vertical density interface. The barotropic tides were known to play the dominant
role in driving the internal tides at the topographic relief or shelf break.This research tries to look at the mechanisms of internal tides generation and propagation in the Kaoping Submarine Canyon off southwestern Taiwan, using Princeton Ocean Model (POM) with different settings. The model was tested with bottom topography of flat, a slope and real water
depth, with and without vertical stratifications. The model settings are grid size 500m, simulate period days, radiation boundary condition at 4 sides. The model forcings are sea level variations at the west side, both semidiurnal tide (M2) and mixed tide (M2+K1) based on OSU tidal model TPXO 6.2. The results suggest that the offshore M2 tidal forcing
can generate large internal tidal currents within the canyon with vertical density stratification. The internal tidal currents at the upper-layer of the canyon lag that of lower-layer 3~5 hours. There is no time lag and no
amplification of current in the canyon if there is no stratification. There is a transition zone of minimum flow at depth of about 100-200m. Below the interface, the amplitude of semidiurnal internal tidal current increased with water depth in the canyon. The simulated density contours suggest a 120m amplitude vertical fluctuation center at 150m depth, with 5¢J temperature fluctuation. The computed baroclinic energy flux indicates that the energy in lower layer of the canyon is stronger than that of upper
layer. The high energy flux appears at the canyon foot and rim, and propagates along the canyon axis landward.
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Geology of the passive margin off New England /Austin, James Albert. January 1979 (has links)
Thesis--Woods Hole Oceanographic Institution/Massachusetts Institute of Technology Joint Program in Oceanography, 1978. / Grant 04-7-158-44104 and 04-8-M01-149. Includes bibliographical references (p. 163-184).
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Duration, rates, and patterns of crustal growth at slow-spreading mid-ocean ridges using zircon to investigate the evolution of in situ ocean crust /Grimes, Craig B. January 2008 (has links)
Thesis (Ph.D.)--University of Wyoming, 2008. / Title from PDF title page (viewed on Mar. 8, 2010). Includes bibliographical references.
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