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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.
611

Subsurface structural evolution along the northern Whittier fault zone of the eastern Los Angeles basin, Southern California

Herzog, David W. 26 January 1998 (has links)
The Whittier fault forms the central part of a fault system extending from the East Montebello fault at Whittier Narrows to the Elsinore fault, which is traced as far as the Mexican border. The Whittier fault forms a restraining bend in this fault system, resulting in uplift of the Puente Hills. The northwestern part of the Whittier fault in the Whittier oil field in the eastern Los Angeles basin strikes approximately N65��W and dips 70-75�� northeast. The fault is near the range front of the Puente Hills northwest of Turnbull Canyon, and within the Puente Hills to the southeast. The central reach of the Whittier fault had normal separation in the Relizian and Luisian stages of the middle Miocene. From the Mohnian through Repettian stages of the late Miocene and early Pliocene, little, if any, offset occurred until the initiation of reverse offset in the Venturian stage of the late Pliocene. A component of right-lateral strike-slip may have been added near the end of the Pliocene, coinciding with the formation of the Elsinore fault. The Workman Hill and Whittier Heights faults may have formed in the late Pliocene to early Pleistocene, coinciding with the possible initiation of strike-slip on the Whittier fault. The present sense of slip on the Whittier fault southeast of the study area is nearly pure right-lateral strike-slip, with a slip rate of 2-3 mm/yr. The northwestern part of the Whittier fault has a component of reverse slip of approximately 1 mm/yr. The amount of strike-slip on this part of the fault was not determined by this study. The Rideout Heights, 304, and 184 low-amplitude anticlines formed in the Whittier oil field area in the late Miocene and early Pliocene. The Rideout Heights anticline is a southwest-verging fault-propagation fold trending northwesterly from the mouth of Turnbull Canyon through the Rideout Heights area. Strata are overturned in the southwest limb of the fold, and normally dipping in the northeast limb; the fold has been cut along its hinge by the Whittier fault. The 304 and 184 anticlines are north-verging and appear to be beddingplane shear folds in the northeast limb of the La Habra syncline. Recent strike-slip on the Whittier fault may have reactivated the 184 anticline, causing uplift of the footwall block south of Turnbull Canyon. North of Turnbull Canyon, the Whittier fault is at the range front with no evidence of Quaternary footwall uplift. The 304 anticline could be a fault-propagation fold from a previously-unknown southwest dipping blind reverse fault south of the Whittier fault; uplift on this fold could also be the cause of footwall uplift south of Turnbull Canyon. Active fault traces, possibly strike-slip, are on or near the Whittier fault south of Turnbull Canyon, but to the north, recent offsets appear to be northeast of the Whittier fault in the Puente Hills. These offsets may represent an attempt of the Whittier fault to straighten itself by bypassing the restraining bend at Turnbull Canyon. so, this movement is too recent to offset conglomerate beds more than a few tens of meters. / Graduation date: 1998
612

Geology and paleoseismology of the Trans-Yamuna active fault system, Himalayan foothills of northwest India

Oatney, Emily M. 09 October 1998 (has links)
Satellite image interpretation, geologic mapping, and paleoseismic trenching are used to investigate the Trans-Yamuna active fault system in the northwestern Doon Valley of the Indian Himalayan foothills. This east-west fault system is subparallel to and crosses the Main Boundary thrust near the structural transition from the Nahan salient to the Dehra Dun reentrant. The Trans-Yamuna active fault system may terminate to the east at a lateral ramp of the Main Boundary thrust. A south-side-up, relatively linear fault trace with variable fault dips suggests that the fault system is high-angle reverse with a component of strike-slip. It is subdivided into the Sirmurital, Dhamaun, and Bharli faults, which probably connect at depth. The Dhamaun fault is exposed where it cuts the late Holocene upper Bhatrog terrace deposit of the Giri River. A paleoseismic investigation of the Sirmurital fault at another Giri River terrace did not expose the fault, but it suggests that late Holocene terrace deposits there may be folded into a syncline parallel to fault strike. The fold axis of the syncline continues into bedrock to the west. Earthquakes in 1905, 1803, or perhaps earlier may have been the source of folding of the fine-grained sediments within this terrace deposit. The Trans-Yamuna active fault system is a secondary hangingwall fault that may accommodate some strain release above the decollement during large-magnitude earthquakes. Strike-slip motion may be related to the lateral translation of the Karakoram fault block and east-west extension of the southern Tibet block as a result of oblique convergence between the Indian and Eurasian plates in the northwest Himalaya. / Graduation date: 1999
613

Lower and Middle Devonian carbonate-platform and outer-shelf-basin deposits flanking Railroad Valley, Nevada

Nelson, Storr L. 21 May 1996 (has links)
Lower and Middle Devonian strata crop out on the former stable carbonate platform that existed in the Quinn Canyon Range, through the carbonate shelf edge in the Pancake Range, to the carbonate slope and outer-shelf basin in the Reveille Range. The strata of the Reveille Range record a transition from deposition on the carbonate platform in the Lower Devonian, to deposition at the carbonate platform margin, to deposition in the outer-shelf basin in the Middle Devonian. Conodonts collected from the base of the Sevy Dolomite yield a kindlei-Zone age, an indication that the Sevy Dolomite is younger than previously recognized. Throughout the Lower and Middle Devonian, carbonate strata of the Pancake Range and Quinn Canyon Range were deposited on the shallow carbonate platform. Conodonts collected from the base of the Lower Alternating Member of the Simonson Dolomite in the Quinn Canyon Range have a slightly older age (serotinus- to costatus Zone) than other eastern Nevada locations. The Lower Devonian Sevy Dolomite was deposited in a shallow carbonate subtidal through supratidal environment and is similar in outcrop throughout the ranges. Petrographic studies show that the samples are lithologically and diagenetically similar, indicating a similar intensity of dolomitization from the precursor calcareous mudstone. The Formation classifies as bioturbated mudstone and wackestone. The Middle Devonian Simonson Dolomite was deposited in shallow carbonate subtidal through supratidal environments. The Simonson Dolomite was affected by Milankovitch Cycles, glacioeustatic oscillations of sea level, producing a characteristic rhythmic bedding. The Middle Devonian Sadler Ranch Formation and Denay Limestone are lithologically and diagenetically different from the shallow water deposits of the Lone Mountain Dolomite, Sevy Dolomite, and Simonson Dolomite. The Sadler Ranch Formation and Denay Limestone were deposited at the carbonate platform edge and on the carbonate slope and outer-shelf basin, respectively. The Sadler Ranch Formation is dolomitized and may be classified as fossiliferous wackestone and mudstone. The Denay Limestone is not dolomitized and is classified as mudstone and fossiliferous grainstone and packstone. Dolomitization in the Paleozoic strata of Nevada is a secondary feature, an early diagenetic replacement of strata which were originally limestone. This replacement process was controlled by transgressions and regressions of the shoreline. Shallow carbonate platform deposits (shelfal and tidal-flat) are dolomitized, whereas deep water outer-shelf basin and slope deposits are not. / Graduation date: 1997
614

The paleoclimatic evolution of the Permian in the Paraná Basin in southern Brazil /

Goldberg, Karin. January 2001 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of the Geophysical Sciences, December 2001. / CD-Rom contains lithological and geophysical logs in Adobe PDF format. Includes bibliographical references. Also available on the Internet.
615

Optical dating of quartz from young deposits : from single-aliquot to single-grain : proefschrift ... door /

Ballarini, Mirko, January 2006 (has links)
Thesis (Doctor)--Technische Universiteit Delft, 2006. / Includes bibliography (p. 134-136).
616

Regional Reservoir compartmentalization within offlaping, top-truncated, mixed-influenced deltas, wall creek member, frontier formation, powder river basin, Wyoming /

Sadeque, Junaid, January 2006 (has links)
Thesis (Ph. D.)--University of Texas at Dallas, 2006. / Includes vita. Includes bibliographical references (leaves 128-141)
617

The geology and stratigraphy of the Tertiary volcanic and volcaniclastic rocks, with special emphasis on the Deschutes Formation, from Lake Simtustus to Madras in central Oregon /

Jay, Jeremy Barth. January 1982 (has links)
Thesis (M.S.)--Oregon State University, 1983. / Typescript (photocopy). One map folded in pocket. Includes bibliographical references (leaves 107-110). Also available online.
618

Silurian bedrock geology of the Muncie area

Glasby, Virginia June 03 June 2011 (has links)
The Silurian rocks in Delaware County, Indiana, include, in ascending order, the Salamonie Dolomite, Limberlost Dolomite, Waldron Formation, and Louisville Limestone, and Mississinewa Shale Member of the Wabash Formation, all of the Niagaran Series (middle Silurian).The oldest exposed Silurian rocks are the Salamonie and the overlying Limberlost Formation (lower Niagaran) are exposed in Irving and Eaton quarries. The Salamonie is 25 feet of apparently reefflank rocks within the Salamonie, with primary dips to 20 degrees, are exposed in Eaton Quarry. The Limberlost, averages six feet and is generally brown, vuggy, dolostone.The Waldron and Louisville formations (middle Niagaran), are exposed in Hoyt, Irving, and Eaton quarries. The Waldron averages six feet and is interbedded grey shale and argillaceous dolostone, and is fossiliferous. It is conformably overlain by about 60 feet of Louisville Formation, predominately argillaceous dolostone with nodular chert and fossils.At Buchanan Quarry, 10 feet of grey dolomitic siltstone and shale of the Mississinewa Member, Wabash Formation, comprise the youngest Silurian strata exposed.Correlation of distinct units within the Louisville between Hoyt, Irving, and Eaton quarries shows considerable lateral continuity and general thinning toward the north.
619

Stratigraphic study of a glacio-fluvial feature near Mount PLeasant, Indiana by Stephen R. Myers. / Glacio-fluvial feature near Mount Pleasant, Indiana.

Myers, Stephen R. 03 June 2011 (has links)
This study was concerned with the origin and stratigraphic relationship of a ridge-swales complex located in and near Mount Pleasant, Indiana. Borehole data, water well logs, seismic refraction surveys, and electrical resistivity surveys were combined to create three cross-sections which illustrate the stratigraphic relationship of the feature under scrutiny. In addition, textural analyses of outwash, esker, and ridge samples were performed to discriminate between outwash and esker material; the results were compared to the ridge samples.The textural analyses failed to discriminate convincingly between esker and outwash; however, the cross-sections display the ridge-valley complex as a broad sheet of outwash sand and gravel subsequently eroded by glacial meltwater.Ball State UniversityMuncie, IN 47306
620

Sequence Stratigraphy of the Cenozoic Pannonian Basin, Hungary

January 1997 (has links)
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.

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