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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
301

Analysis of coastal geomorphological processes on a boreal coarse clastic barrier : Long Pond Barachois, Conception Bay, Newfoundland /

Pittman, Donald Paul, January 2004 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2005. / Bibliography: leaves 216-234.
302

Geologic map and structural analysis of the Twin Rocks 7.5 minute quadrangle, Wayne County, Utah /

Sorber, Samuel C., January 2006 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Geology, 2006. / Includes bibliographical references.
303

Geology, geomorphology, and dynamics of mass movement in parts of the Middle Santiam River drainage basin, western Cascades, Oregon /

Hicks, Bryan A. January 1982 (has links)
Thesis (M.S.)--Oregon State University, 1982. / Typescript (photocopy). Some maps folded in pocket. Includes bibliographical references (leaves 156-169). Also available via the World Wide Web.
304

Motion and evolution of the Chaochou Fault, Southern Taiwan

Hassler, Lauren E. 01 November 2005 (has links)
The Chaochou Fault (CCF) is both an important lithologic boundary and a significant topographic feature in the Taiwan orogenic belt. It is the geologic boundary between the Slate Belt to the east, and the Western Foothills to the west. Although the fault is known to be a high angle oblique sinistral thrust fault in places, both its kinematic history and its current role in the development of the orogen are poorly understood. Field fabric data suggest that structural orientations vary along strike, particularly in the middle segment, the suspected location of the intersection of the on-land Eurasian continent-ocean boundary and the Luzon Island Arc. Foliation/solution cleavage is oriented NE-SW and in the northern and southern sections, but ESE-WNW in the middle segment. Slip lineations also reveal a change in fault motion from dip-parallel in the north to a more scattered pattern in the south. This correlates somewhat with recent GPS results, which indicate that the direction of current horizontal surface motion changes along strike from nearly perpendicular to the fault in the northern field area, to oblique and nearly parallel to the fault in the southern field area. The magnitude of vertical surface motion vectors, relative to Lanyu Island, decreases to the south. Surface morphology parameters, including mountain front sinuosity and valley floor width/valley height ratio indicate higher activity and uplift in the north. These observations correlate well with published apatite/zircon fission track data that indicate un-reset ages in the south, and reset ages in the northern segment. Geodetic and geomorphic data indicate that the northern segment of the CCF and Slate Belt are currently undergoing rapid uplift related to oblique arc-continent collision between the Eurasian continent and the Luzon arc. The southern segment is significantly less active perhaps because the orogen is not yet involved in direct arc-continent collision.
305

Motion and evolution of the Chaochou Fault, Southern Taiwan

Hassler, Lauren E. 01 November 2005 (has links)
The Chaochou Fault (CCF) is both an important lithologic boundary and a significant topographic feature in the Taiwan orogenic belt. It is the geologic boundary between the Slate Belt to the east, and the Western Foothills to the west. Although the fault is known to be a high angle oblique sinistral thrust fault in places, both its kinematic history and its current role in the development of the orogen are poorly understood. Field fabric data suggest that structural orientations vary along strike, particularly in the middle segment, the suspected location of the intersection of the on-land Eurasian continent-ocean boundary and the Luzon Island Arc. Foliation/solution cleavage is oriented NE-SW and in the northern and southern sections, but ESE-WNW in the middle segment. Slip lineations also reveal a change in fault motion from dip-parallel in the north to a more scattered pattern in the south. This correlates somewhat with recent GPS results, which indicate that the direction of current horizontal surface motion changes along strike from nearly perpendicular to the fault in the northern field area, to oblique and nearly parallel to the fault in the southern field area. The magnitude of vertical surface motion vectors, relative to Lanyu Island, decreases to the south. Surface morphology parameters, including mountain front sinuosity and valley floor width/valley height ratio indicate higher activity and uplift in the north. These observations correlate well with published apatite/zircon fission track data that indicate un-reset ages in the south, and reset ages in the northern segment. Geodetic and geomorphic data indicate that the northern segment of the CCF and Slate Belt are currently undergoing rapid uplift related to oblique arc-continent collision between the Eurasian continent and the Luzon arc. The southern segment is significantly less active perhaps because the orogen is not yet involved in direct arc-continent collision.
306

Relationships between stream geomorphology and fish community structure and diversity in Maine /

Gaenzle, Emily, January 2002 (has links)
Thesis (M.S.) in Ecology and Environmental Sciences--University of Maine, 2002. / Includes vita. Bibliography: leaves 57-59.
307

An analysis of small stream networks located on reclaimed surface coal mines, Morgantown, WV

Smith, Jocelyn. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains viii, 91 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 79-82).
308

Morphologies and controls on development of Pliocene-Pleistocene carbonate platforms : Northern Carnarvon Basin, Northwest Shelf of Australia

Goktas, Pinar 15 November 2013 (has links)
The detailed morphologies, evolution and termination of Neogene tropical carbonate platforms in the Northern Carnarvon Basin (NCB) on the passive margin of the Northwest Shelf of Australia reveal information on the history of local oceanographic processes and changing climate. Cool-water carbonate deposition, dominant during the early-middle Miocene, was superseded by a siliciclastic influx, which prograded across the shelf beginning in the late-middle Miocene during a period of long-term global sea-level fall. The resulting prograding clinoform sets, interpreted as delta lobes, created relict topographic highs following Pliocene termination of the siliciclastic influx (Sanchez et al., 2012a; 2012b). These highs created a favorable shallow-water environment for subsequent photozoan carbonate production. A composite, commercial 3D seismic volume allows investigation of the temporal and spatial evolution of the resulting Pliocene-Pleistocene carbonate platforms. Initiation of carbonate development, in addition to being a response to cessation of siliciclastic influx and the existence of suitable shallow-water substrate, was also influenced by the development of the warm-water Leeuwin Current (LC), flowing southwestward along the margin. Four flat-topped platforms are mapped; each platform top is a sequence boundary defined by onlap above and truncation below the boundary. Successive platforms migrated southwestward, along-strike. Internally, platforms have progradational seismic geometries. The mapped platform tops are large (≥ 10 km wide). Evidence of karst (e.g., v-shaped troughs up to 50m deep and ~1 km wide and broader karst basins up to 20 km2 coverage area) on platform tops suggests episodic subaerial exposure that contributed to the demise of individual platforms. The most recent platform, platform 4, is unique in having interpreted reefs superimposed on the progradational platform base. The base of these reefs now lies at ~153 m and the reefs may therefore have developed post-LGM (~21 Ka). The reefs subsequently drowned, with drowning possibly aided by turbidity associated with formation of adjacent sediment drifts and weakening and strengthening LC during the late Pleistocene. The progressive drowning and termination of platforms from northeast to southwest along strike may result from differential compaction of the deltaic substrate or differential tectonic subsidence caused by the collision at the Banda Arc between the Australian and Pacific plates / text
309

Quantifying geomorphic change to a point bar in response to high flow events using terrestrial lidar, White Clay Creek, DE

Orefice, Michael J. 24 October 2015 (has links)
<p> Light Detection And Ranging (LiDAR) data can be used to accurately model three- dimensional surfaces for quantifying fluvial erosion and deposition. Terrestrial LiDAR is typically used for monitoring banks, but can be used for monitoring planar forms such as point bars. Point bars are topographic features that form on the convex bank of a meander. While point bars are considered to be formed by depositional processes, they display features such as chute channels and scour holes that suggest that erosion, due to high flow events, may significantly influence point bar evolution. Through the use of Terrestrial Laser Scanning (TLS), we observed how a point bar on the White Clay Creek near Newark, Delaware, responded to a flood event with a return period of 6.1 years, and to multiple small events over a 1 year period with return periods between 1.00 and 1.25 years. Scans of the point bar were completed on April 11, 2014, May 8, 2014, and April 16, 2015. Scans were referenced to a common coordinate system, scan data representing vegetation points were removed, and three 0.1 m x 0.1 m gridded Digital Elevation Models (DEMs) were created from the remaining data. DEMs of Difference (DoDs) were calculated by subtracting the cell values in subsequent DEMs and by thresholding out positional and surface roughness errors. The 6.1 year flood that occurred between the April 11, 2014 scan and the May 8, 2014 scan resulted in 88.53 m<sup>3</sup> of erosion and 39.12 m<sup>3</sup> of deposition. The net volumetric change was -49.40 m<sup>3</sup> over an area of 631.72 m<sup>2</sup>. The smaller events that occurred between the May 8, 2014 scan and the April 16, 2015 scan resulted in 13.33 m<sup>3</sup> of erosion and 53.46 m<sup> 3</sup> of deposition. The net volumetric change was x i 40.13 m<sup> 3</sup> over an area of 620.74 m<sup>2</sup>. Our results suggest that 1) sediment deposited on point bars is eroded frequently by flood events; and 2) TLS can provide useful estimates of erosion and deposition. Although our results are for a short period, longer datasets can be used to calculate sediment residence times for point bar deposits. Additionally, we can gain a better understanding of how point bar deposits are preserved in the geologic record. This information is useful for creating accurate sediment budgets, remediating contamination issues, and interpreting geologic history.</p>
310

Geomorphology of the Swisshelm scarp, Cochise County, Arizona

Druke, Patricia Ann January 1979 (has links)
No description available.

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