No description available.

Thesis (M.A.)--State University of New York at Binghamton, Geological Sciences and Environmental Studies Department, 2006. / Includes bibliographical references.

The Cocos Gap is a deeper portion, or saddle, of the Cocos Ridge and forms part of the western boundary of the Panama Basing It is probably typical of saddles within most submarine ridges, In order to determine the mechanisms controlling sediment dispersal, the nature and sources of the sediments at 23 core locations were defined by hydrodynamic size separation (> 63, 2- 63, <2 micron) and microscopic or X-ray diffraction analysis of the individual fractions. In addition, calcium carbonate, organic carbon, opal and quartz determinations were made for the total sediment. The silt sized fraction was resolved into eight textural modes, The coarse modes reflect the progressive breakage and winnowing of the corase fraction (foraminifera) under the influence of bottom currents and gravity. Above 2000 m mechanical breakdown, winnowing and relocation by bottom currents mask the effects of depth related dissolution of the carbonate fraction, Intermediate modes in general represent a transitional facies with both biogenic and terrigenous influences, while the finest modes characterize a distal regime of clay deposition, The clay fraction is amorphous material with very low percentages of well crystallized clays. Three main sources and transport paths were recognized, including one associated with the circulation of the Panama Basin. Sedimentation within the Gap is controlled by local processes, predominantly the interaction between tidally induced intensification of bottom water flow and directional (thermohaline) flow. The steep' ness of the sea floor slope is a major factor controlling the efficiency of winnowing of the sediment away from certain higher elevations (biogenic source areas) to the sheltered parts and flanks of the ridge. Superimposed upon this sediment dispersal is the influx of terrigenous material carried by directional bottom currents that operate as postulated upper and lower contour currents along the flanks of the ridge. The crest of the Cocos Gap acts as a catchment area for the biogenic components, while the adjacent more sloping region, the sub-plateau, acts as a source area. The extreme breakage of the foraminifera is most likely a function of the tidally induced intensification of the bottom water flow, characteristic of many shallow ridges, and is probably most significant in the subplateau. Hydrographic data indicates that there is no significant transport of bottom water across the Cocos Gap into the Panama Basin, but downslope transport of carbonate and siliceous fragments and minerals from the Gap into the basin is associated with cyclical tidal bottom water flow. / Graduation date: 1976

The sequence stratigraphy of the middle Eocene-Pliocene of the Pannonian Basin permits to differentiate fifty-nine depositional sequences. An earlier compressional Paleogene basin in the central and eastern Pannonian Basin is unconformably overlain by a Neogene extensional basin. Tectonic regimes interacted with transgressive-regressive facies cycles. The boundaries of these cycles coincide with regional stage boundaries. Unconformities separating these cycles mark the episodic closure of connections between the Pannonian Basin and the European epicontinental seas from Oligocene through middle Miocene time. The unconformities are the result of short-term glacio-eustatic falls, sometimes enhanced by tectonic events. Within the limits of biostratigraphic resolution during the Eocene-middle Miocene, many of the sequences of the Pannonian Basin correlate well with the sequences proposed by Haq et al. (1987). However, eight sequences, i.e. one in the Lutetian, three in the Bartonian, one in the Priabonian, one in the Rupelian and two in the Burdigalian, were not identified by Haq et al. (1987). The sequences and their boundaries are directly correlated with global oxygen isotope events. Glacioeustasy generates sequence boundaries beginning as early as the middle Eocene. Within the lacustrine setting of the Pannonian Basin (late Miocene- Pliocene time) relative lake level changes appear to control the overall sequence development. However, other minor variables, the sediment supply and the topography of the initial depositional surface were additional controlling factors. Thus differences in the physiography of the basin lead to totally different sequence types that all reflect to lake level fluctuations. In lateral direction, during a short time period, these lacustrine sequences are more sensitive to changes in the initial depositional profile and sediment supply. / pages 390 and 396 are missing from text.

Thesis (M.C.E.)--University of Delaware, 2009. / Principal faculty advisor: Jack A. Puleo, Dept. of Civil & Environmental Engineer. Includes bibliographical references.

Thesis (Ph. D.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 242-257).

Thesis (M.A.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 146-156).

Thesis (M.A.)--University of Hawaii at Manoa, 2005. / Includes bibliographical references (leaves 146-156). Also available via World Wide Web.

Thesis (M.S.)--Oregon State University, 2002. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 2002. / Typescript (photocopy). Includes bibliographical references (leaves 70-72). Also available online.