Browsing by Subject "Sedimentation and deposition"
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Item A sedimentary study of the Glorietta Sandstone of New Mexico(Texas Tech University, 1949-05) Huntington, George CNot availableItem An Analysis of Depositional Environments and Diagenesis of Tertiary Volcanic Sediment Deposits of the Northeastern Lago de Atitl�n Region, Guatemala(Texas Tech University, 1979-12) Sanford, William CaseyNot Available.Item An analysis of dust storms as a factor in urban runoff quality in Lubbock, Texas.(Texas Tech University, 1975-12) Bell, David EarlNot availableItem An analysis of volcaniclastic sediments, Pacific offshore, Guatemala(Texas Tech University, 1980-05) Gonzales, EduardoThis thesis describes extensive experimental implementations of multiplex holography for use in representing two-dimensional spacevariant optical systems. Diffusers are used to encode the reference beams for effective crosstalk suppression. The problem of hologramto-hologram crosstalk is both analytically and experimentally examined, and various methods for its suppression are discussed. The merits of using ground glass diffusers for crosstalk suppression are experimentally investigated, and the superiority of chirped-wave diffuser illumination over plane-wave illumination in crosstalk suppression is demonstrated. The first implementations of binary-coded diffuser masks for crosstalk suppression in multiplex holography are shown. The experimental proof of coherent addition in overlapping holographic outputs is presented, and the first holographic representation of an extremely space-variant optical system is shown. The holographic representation of an optical system using a large (10 x 10) array of input sampling points is also shown. With a working 2-D space-variant holographic processor thus available, a variety of space-variant processing operations for future investigations are suggested.Item Authigenic clays and stylolites in the carbonate reservoirs of the Permian Basin(Texas Tech University, 1997-05) Kumar, AnishAuthigenic clay minerals are found in back-reef carbonate rocks ofthe Upper Permian Artesia Group ofthe northwestern shelf of the Delaware Basin. The authigenic clays are located in the vugs and pore spaces of the carbonates. Stylolites from these rocks do not show clays of authigenic origin, however detrital clays and other minerals such as illite, quartz, feldspar, and pyrite are accumulated in the stylolite seams in these carbonates. Authigenic clays in pores and vugs of carbonate samples were studied using x-ray diffraction, and electron imaging such as SEM, TEM, and STEM. Dickite is the predominant authigenic clay mineral. It occurs mostly in euhedral hexagonal platelets. Authigenic illite is rarely observed, and it occurs as laths and fibers.Item Characterization, variations, and controls of reef-rimmed carbonate foreslopes(2008-05) Playton, Ted; Kerans, C. (Charles), 1954-Allochthonous, seaward-dipping deposits that flank reef-rimmed carbonate platforms (reef-rimmed carbonate foreslopes) display a spectrum of deposit types, seismic-scale stratal architecture, and bed-scale heterogeneity due to diverse sediment sources and resedimentation processes. This variability has resulted in a lack of consistent characterization approaches, and has made the development of predictive models that link carbonate foreslope deposit types to stratal architecture challenging. This study uses data from outcrops, including the Upper Devonian of the Canning Basin, Western Australia and the Upper Permian of the Delaware Basin, West Texas, and examples from literature to provide 1) an approach for characterizing reef-rimmed carbonate foreslopes in terms of deposit types and architecture, 2) conceptual models that outline the variations that exist, and 3) discussion of the intrinsic and extrinsic factors that control the observed variations. The primary depositional elements that construct reef-rimmed carbonate foreslopes can be categorized as 1) debris elements (breccias and blocks) from brittle reef failure, 2) grain-dominated elements (grainstones and rudstones) from offbank transport of sand and gravel, and 3) mud-dominated elements (mud-dominated fabrics) that record relative foreslope quiescence and fine-grained periplatform shedding. The fundamental stratal geometries observed are 1) accretionary margins, characterized by margin-toforeslope interfingering and clinoforms, and 2) escarpment margins, characterized by aggrading-retrograding margin architecture and foreslope onlap. The combinations of element proportions, element distribution, stratal geometry, bed- to bedset-scale architecture, and depositional profile scale that exist in carbonate foreslopes range widely, warranting multiple depositional models. The deposit type and architectural variations observed in detail from Upper Devonian and Upper Permian outcrops of the Canning Basin, Western Australia, and the Delaware Basin, West Texas, respectively, are linked to differing scales of superimposed accommodation change and reef faunal assemblage. Observations from other outcrops and extensive literature review display further controlling factors that affect carbonate foreslope development, such as platform morphology, oceanographic conditions, slope height, tectonic setting, and siliciclastic input, suggesting a multi-variable interplay of controls. These controls dictate the productivity and resedimentation of the contributing sediment factories, and/or influence the development of the carbonate platform system as a whole. Knowledge and classification of carbonate foreslope deposit types, architecture, and controls not only improve understanding of these complex systems, but also allow for the development of predictive relationships for economic purposes.Item Clastic wedge development and sediment budget in a source-to-sink transect (Late Campanian western interior basin, SW Wyoming and N Colorado)(2009-12) Gomez, Carolina Andrea; Steel, R. J.The problem of how sand and mud was distributed downslope, within linked alluvial-brackish water-marine shoreline systems of an extensive clastic wedge is addressed here. The Iles Clastic wedge accumulated over a time period of a few million years (my), and its component high-frequency regressive-transgressive sequences have a duration of a few 100 thousand years (ky). The sediment partitioning study provides insight into where the thickest sandstones and mudstones were located, and generates a model that can be applied to improving the management of hydrocarbons or water resources. A 300 km 2-D study transect across the Iles Clastic Wedge in SW Wyoming and N Colorado included subsurface well log information and outcrop stratigraphic columns. This information was used to correlate high-frequency sequences across several hundred kilometers, characterize depositional processes from proximal to distal reaches, develop a sediment partitioning model, and understand the role of the likely drivers in the development of the wedge and its internal sequences. The main results of this study are: (1) The Iles Clastic Wedge spans 3 my (500 m thick) and is composed internally of 11 sequences of 200-400 ky, each of which have significant regressive-transgressive transits of up to 90 km. Sediment partitioning analysis shows that within the regressive limb of the large wedge, the component regressive compartments tend to thicken basinwards, whereas transgressive compartments thicken landwards. This geometry is driven by preferential erosion in proximal areas during regression, bypassing much sediment to the marine shorelines, and transgressive backfilling into proximal areas previously eroded more deeply. (2) The greatest concentration of sands tends to be located in the proximal fluvial and estuarine facies of the transgressive compartments and within the medial shoreline/deltaic facies of the regressive compartments. (3) As the high-frequency sequences developed, the effectiveness of basinward sand partitioning reaches a maximum value near the peak regression level of the wedge, reflecting stronger erosion and sediment bypass during this times. (4) The development of the Iles Clastic Wedge was influenced by both tectonic and eustatic drivers, with important tectonic control in the upstream reaches. On a 4th-order timescale, the Iles Wedge internal sequences were likely influenced mainly by eustasy.Item Coastal sedimentation of volcanogenic sands, Guatemala(Texas Tech University, 1978-05) Boothby, Donald RoyNot availableItem Controls on the development of clastic wedges and growth strata in foreland basins : examples from Cretaceous Cordilleran foreland basin strata, USA(2008-05) Aschoff, Jennifer L., 1978-; Steel, R. J.Tectonic signatures such as growth strata, clastic progradation, detrital composition, thickness trends, paleoflow shifts, lithofacies distribution, and vertical stratigraphic stacking patterns provide the basis for a range of tectonic/structural interpretations. Complete understanding of the application and limitations of tectonic signatures is important to maintain consistency and reduce uncertainty of interpretations that use them. This study provides insight into the external controls on two frequently used tectonic signatures in foreland basins: (1) growth strata, and (2) clastic wedge progradation. First, two syntectonic unconformity types are recognized in non-marine, Cenomanian growth strata adjacent to the Sevier thrust-belt in southeastern Nevada, USA. Unconformities with larger angular discordance (>10°, “Traditional Type”) developed when uplift outpaced sediment accumulation. More subtle unconformities with less discordance (2-10°, “Subtle Type”) developed when sediment accumulation nearly kept pace with uplift. Increasing sediment supply with positive net accommodation, allows syntectonic deposits to aggrade above a growing structure, with no change in uplift rate. Hence, sediment supply and regional accommodation impart an important control over growth strata geometries that are often interpreted on the basis of tectonics alone. Identification of unconformity types in growth strata can therefore document additional phases of uplift, particularly for intervals where sediments aggraded above an active structure due to higher sediment supply during regional subsidence, or sea level rise. Second, an anomalous, Campanian clastic wedge is identified in Cordilleran Foreland basin fill, Utah and Colorado. The complex internal architecture, tide-dominated facies and characteristic flat-to-falling shoreline stacking patterns of the wedge reflect rapid progradation of wide (60-80 km), embayed, tide-influenced shorelines; these characteristics distinguish the anomalous wedge from the underlying and overlying clastic wedges in the basin. A high-resolution regional correlation and isopach maps for the anomalous wedge provide evidence that extensive clastic progradation was coeval with both Sevier- and Laramide-style deformation. Stratigraphic relations suggest that development of the anomalous character of Wedge B was due to uplift of a Laramide structure within the foredeep, and possibly enhanced by reduced dynamic subsidence.Item Deltaic Sedimentation on an Active Volcanic Continental Margin, Rio Achiguate, Pacific Coast, Guatemala(Texas Tech University, 1978-12) Greer, Efford WayneNot Available.Item Deposition and diagenesis of the lower cretaceous Antlers Sandstone on the Young Ranch, Nolan County, Texas(Texas Tech University, 2001-12) Wood, Leonard WayneThe Lower Cretaceous Antlers Sandstone on the Young Ranch is the time equivalent to the Twin Mountains, Glen Rose, and Paluxy Formations of the Cretaceous Trinity Group. The Antlers represents the initial deposition of sediment onto the Wichita Paleoplain unconformity of North and West-Central Texas. The Antlers on the Young Ranch is interpreted as a bed-load channel deposit consisting of sandstone and gravelly sandstone. On the Young Ranch, the Antlers Sandstone is a discontinuous sandstone that is only present where post-depositional cementation by quartz and microquartz has occurred, or where the sandstone is overlain by uneroded limestones of the Walnut Formation. The silicification is similar to sllcretes (quartz cemented soils) found in other Mesozoic and Cenozoic sediments. Petrographic analysis of the Antlers silcrete on the Young Ranch reveals large amounts of syntaxial overgrowths on detrital quartz grains. Microquartz cement is also observed, although it is not present in the large volumes like the quartz overgrowths. Syntaxial quartz overgrowths were observed when using the SEM, as well as the small euhedral and subhedral crystals characteristic of microquartz. The reconstruction of the diagenetic history of the Antlers Sandstone on the Young Ranch indicates that the Antlers most resembles a groundwater silcrete. The maximum depth of burial that the Antlers could have undergone (< 160 ft.) excludes deep burial (>3 km), therefore silicification must have formed under shallow burial conditions (diagenetic quartzarenite or silcrete). Moreover, the multicolored nature of the Antlers in outcrop indicates shallow silicification (silcrete). The predominance of quartz overgrowths (--70%) compared to mircoquartz cement (--30%) indicates a groundwater silcrete as opposed to a pedogenic silcrete. The absence of numerous soil features also supports the interpretation of the Antlers being primarily a groundwater silcrete. The silicification of the Antlers sandstone probably occurred penecontemporaneous with Antlers deposition, but could have occurred during post-Edwards exposure. Fluctuations in the water table on the Young Ranch are the likely mechanism for silicification, which transported silica liberated from intraformational sources such as dissolutloned chert and polycrystalline quartz grains. This accumulation of silica from internal sources aids in the Interpretation of the Antlers Sandstone on the Young Ranch being classified as a paleosilcrete horizon.Item Deposition and diagenesis of the Smackover Formation, south-central Alabama(Texas Tech University, 1977-12) Leiker, Loren MichaelNot availableItem Deposition and Diagenesis of the Yates Formation, Guadalupe Mountains and Central Basin Platform(Texas Tech University, 1973-05) Franco, Lamberto AThe Middle Permian Yates Formation of the Northwest Shelf and Central Basin Platform contains deposits which accumulated in the following depositional environments: 1) reef, 2) backreef apron, 3) lagoon, 4) intertidal zone, 5) coastal sabkha, 6) continental sabkha, and 7) deflation flat. Outer shelf deposits consist predominantly of carbonates; middle and inner shelf deposits consist dominantly of clastics containing evaporites. Artesia Group coastal- and continental sabkha deposits contain an assemblage of sulfate crystals and nodules similar in all aspects to that described from the southern margin of the Persian Gulf. Sulfates precipitated interstitially within coastal- and continental sabkha deposits include lensoid and bladed crystals and rosettes of anhydrite after gypsum and nodular anhydrite. Continental sabkha brine pan (salina) deposits contain laminar anhydrite with needle crystals of anhydrite pseudomorphous after gypsum. Early dolomitization of carbonate deposited in coastal sabkhas occurred. Pseudomorphic- and neomorphic replacement of gypsum by anhydrite and replacement of carbonate by sulfate occurred in both coastal- and continental sabkha deposits. During high stands of sea level, under arid climates, coastal- and continental sabkha and deflation flat deposits prograded seaward, infilling lagoons, and extensive evaporite-bearing deposits were spread over middle and outer shelf areas. During maximum low stands of sea level, outer-and portions of middle shelf areas received increased rainfall while much of the middle shelf and the entire inner shelf remained arid. Subaerially exposed subtidal-intertidal carbonates of the outer shelf area were subjected to early fresh water diagenesis and became mineralogically stabilized (to calcite), leached and lithified; paleoleaching and replacement of sulfates by length-slow chalcedony also took place in the belt of increased rainfall, pisolitic caliche soils formed in granular backreef carbonates and in sandy parent materials. During burial, subtidal-intertidal limestones, stabilized and lithified in a fresh water diagenetic environment, became dolomitized and preexisting leached porosity was occluded by sulfate precipitation; in uncemented sands epitaxial overgrowth of quartz on quartz grains and orthoclase on orthoclase grains was followed by precipitation of dolomite and anhydrite cements, Uplift of Yates sediments in Late Cretaceous-Tertiary time initiated another major episode of fresh water diagenesis which is still in progress and the following reactions are recorded: 1) sulfates have been subjected to leaching, replacement by calcite and length-slow chalcedony and hydration of anhydrite (to gypsum), 2) enlargement of fractures in carbonates by ground water solution, 3) cementation by calcite and length-fast chacedony.Item Deposition, diagenesis and porosity relationships of the Mississippian Chappel limestone, Shackelford County, Texas(Texas Tech University, 1978-12) Washburn, Judith Rena HintonNot availableItem Deposition, diagenesis and porosity relationships of the Odom Limestone(Texas Tech University, 1978-08) Webb, ChriscynthiaNot availableItem Deposition, Diagenesis, and Porosity Relationships of the Lower San Andres Formation, Quay and Roosevelt Counties, New Mexico(Texas Tech University, 1979-05) Worthen, John AldrichNot Available.Item Depositional and diagenetic history of the late Triassic Dockum Group, Young Ranch, Nolan County, Texas(Texas Tech University, 2002-05) Slayden, Jason PThe Late Triassic Dockum Group is a series of continental sediments comprised of lacustrine, deltaic, and fluvial deposits. Dockum sediments are found in Eastern New Mexico, Colorado, and West Texas, Oklahoma, and Kansas. The Santa Rosa and Trujillo Formations represent the Dockum Group on the Young Ranch, Nolan County, Texas. Santa Rosa and Trujillo Formations are fluvial deposits consisting of alternating layers of sandstone and conglomerate. These formations are found on the same topographic level on the ranch. Identification of the Santa Rosa and Trujillo formations can be made through petrographic and paleocurrent analysis. The Santa Rosa Formation tends to be more quartzose and arkosic, while the younger Trujillo Formation is more lithic, with an abundance of metamorphic rock fragments and rare volcanic rock fragments. The Santa Rosa Formation has a reported sediment provenance in the present day Wichita-Arbuckle Mountains. Santa Rosa paleocurrent direction on the Young Ranch trend toward the south. The Trujillo Formation has a reported provenance in the lower Ouachita Tectonic Belt. Trujillo paleocurrent directions on the Young Ranch trend toward the north. Therefore, the paleocurrent analysis on the Young Ranch supports the reported Santa Rosa and Trujillo sediment provenances. Lithofacies types and vertical sequences along with a muitistoried channel stacking architecture indicate a braided fluvial system for the deposition of the Santa Rosa Formation. The presence of the Trujillo Formation at the same topographic level on the ranch leads to the conclusion of deposition in two incised valleys. Diagenetic history of the Dockum Group is marked by a variety of cementation events. Kaolinite and iron oxide occurred as early, shallow burial cementation. Zoned dolomite cement was emplaced during burial. Quartz overgrowths and microcrystalline quartz cement formed during Early Cretaceous Edwards exposure due to pedogenic silerete formation in the overiying Lower Cretaceous Antlers Sandstone. Dedolomite/Poikilitopic calcite formed because of dissolution of the Kirsehberg Evaporite during Early Cretaceous Edwards exposure. Desiccation of recent freshwater springs precipitated gypsum as the final diagenetic event.Item Depositional dynamics of the Brushy Canyon Formation, Delaware Basin, Texas(Texas Tech University, 1966-05) Germain, Louis Charles St.The Brushy Canyon Formation, lowermost of the DeLaware Mountain Group, represents a network of submarine channel and overbank deposits, The site of deposition, the Delaware basin, was analogous to present deep basins off the coast of southern California, such as San Pedro, Sc.nta Monica, and San Diego basins. Because recent data from present oceans indicate that submarine channels like those in the Delaware basin initiate at the mouths of submarine canyons, the existence of numerous submarine canyons along the margin of the ancient Delaware basin is inferred. By analogy with the above recent examples, sediment was probably delivered by tidal and longshore current action into the heads of submarine canyons which extended back onto the platform. Subaqueous bottom flows initiated by earthquakes, storm generated waves, or by overloading, transported sediment down the canyons and into the deep basin via the subsea channels. The coarser material remained in the channels which extended many miles beyond the canyon mouths, whereas much of the finer material spilled over the channel margins and produced natural Levees and finely laminated overbank deposits. These overbank deposits are much Like the flood plain deposits made by subaerial streams. Current flow data obtained from the Brushy Canyon Formation are remarkably unidirectional, which seems to be a characteristic of sediment deposited by this mechanism. The prevailing current direction is southeast (i, e,, basinward), perpendicular to the northeast-southwest trending platform margin.Item Depositional dynamics of the Queen Formation, New Mexico and Texas.(Texas Tech University, 1967-06) Williams, Karl W.Not availableItem Depositional environment and diagenesis of the Viking Formation, Joffre Field, Alberta, Canada(Texas Tech University, 1979-05) Markey, Daniel GeneNot available
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