Browsing by Subject "Stratigraphic"
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Item A Gravity and Magnetic Investigation of the Amarillo Uplift(Texas Tech University, 1969-05) Danbom, Stephen HNot Available.Item A petrographic study of the subsurface Gallup Sandstone of San Juan County, New Mexico(Texas Tech University, 1956-08) Williams, Jack R.Recent exploration by petroleum companies has resulted in renewed interest in the subsurface Gallup Sandstone of the San Juan Basin, New Mexico. The present study provides detailed petrographic descriptions of samples from six wells and interpretation of the data obtained. Locations of the six wells are such that they follow the line of strike of the formation, and lithologies are similar at all locations. Quartz is the predominant mineral in all cases, with cacite being the most important cementing agent. The sporadic occurrence of siliceous cement is fre31quent enough to present a factor for consideration in any program of rock treatment for the purpose of increasing permeability. The most favorable area for additional exploration is believed to be to the south and southwest of the line of wells studied.Item A Sedimentary Analysis of the Queen and Grayburg Formations of Southeastern New Mexico(Texas Tech University, 1958-05) Graves, Frank DouglasNot Available.Item A study of two isolated Cambrian stromatolitic outcrops, Mason and McCulloch counties, Texas(Texas Tech University, 1987-05) Portnoy, Michael BenjaminNot availableItem Applications of conodonts in resolving Pennsylvanian-Permian stratigraphic problems in north-central Texas, New Mexico, Colorado, and Kansas(Texas Tech University, 2002-08) Keairns, Carter EwingPennsylvanian-Permian strata of midcontinent North America comprise numerous cyclothems that are the result of repetitive sea-level changes that produced multiple alternations of marine and non marine facies. Placement of chronostratigraphic boundaries within cyclothems is problematic because the variations in sea-level do not allow a continuous representation of marine facies. This creates gaps in the faunal (and floral) record across potential series and stage boundary intervals. Conodont faunas were collected from localities in north-central Texas, Kansas, Oklahoma, and the Sacramento Mountains of New Mexico. These collections were analyzed for biostratigraphically significant faunas that could delineate, with greater resolution, the Late Pennsylvanian Missourian-Virgilian Boundary. Size criteria, in particular the use of adults not juveniles for index species is addressed, determining that indeed size does matter, and that adult forms are the only platforms that should be considered as biostratigraphically significant. Two new morphotypes of Streptognathodus, Streptognathodus sp. C and Streptognathodus sp. D were identified on the basis of carina length and termination relative to platform length. These new morphotypes combined with existing species Streptognathodus firmus, Streptognathodus pawhuskaensis, and Idiognathus simulator, were sufficient to develop diagnostic faunal zones across the boundary interval. Correlations were based on first appearances of three streptognathodid species, and then a second level of confidence obtained with percentages of species in successive faunas. The newly developed zonations was successfully used to correlate the Stanton, South Bend, and Iatan cycles of midcontinent Kansas with the Upper Winchell, Placid- Ranger dual cycle, and Colony Creek of north-central Texas. The new zonation was extended into New Mexico permitting correlation of the Missourian-Virgilian boundary strata (South Bend cycle) near cycle 2C-5a (of Raatz). The majority of Dry Canyon samples were stratigraphically above the boundary, as evidenced by the presence of the conodont I. lohatulus, and two forms of S. virgilicus that resemble the new morphotypes S. sp C and S. sp. D. It appears as though the trend of a shortening carina, that was useful at the Missourian-Virgilian boundary may 'reset' and repeat itself higher in the Virgilian. In Central Colorado, conodont collections from the Kerber and Sharpsdale formations (Morrowan- Atokan) were assessed for possible biostratigraphic correlation to other regions of Colorado. The carbonates of the upper Kerber and lower Sharpsdale are latest Morrowan based on the conodont data. Recommendations are to sample the Central Colorado equivalent, the Belden Shale for additional, and hopefully, diagnostic conodont faunas.Item Benedum Field of Upton and Reagan Counties, Texas(Texas Tech University, 1951-01) Nixon, Achilles HarryNot Available.Item Biostratigraphy and paleoecology of holothurian sclerites from the Pinery Member, Bell Canyon (Permian) of the Delaware Basin of West Texas(Texas Tech University, 1977-08) Wernlund, Russell J.Not availableItem Classification and characterization of recently buried soils in the southern High Plains(Texas Tech University, 2002-08) Anderson, Joseph GregoryThe Southern High Plains is an extensive plateau, which lacks any major topographic variation. ReUef is provided locally by several types of landforms on the otherwise flat landscape of the Southern High Plains. Dunes, comprised of reworked Holocene eolian sediments, occur in the western and southwestern parts of the area. Thousands of small depressions, or playa lakes, dot the landscape. Some large depressions or basins, most of which are occupied by salinas (ephemeral saline lakes), also occur. In addition, there are several NW-SE trending draws narrow, dry valleys), ancient headwaters of the Red, Brazos, and Colorado Rivers, incised in the surface of the Southern High Plains. This study was focused on soils occurring within the draws and slightly depressed areas in the southwest part of the Southern High Plains. The draws and depressions have been partially filled with aluvial and eolian sediments in Late Pleistocene and Holocene tune (Holliday, 1995). Also, in selected locations, the draws and depressions have up to a meter of sediments deposited since agriculture, including cattle grazing, was initiated in the area.Item Conodont Biostratigraphy and Paleoecology of the Hegler and Pinery Members, of the Bell Canyon Formation (Permian) in the Delaware Basin of West Texas.(Texas Tech University, 1975-12) Sturm, John JNot Available.Item Conodont biostratigraphy of the Skinner Ranch and Hess Formations (Permian), Glass Mountains, West Texas(Texas Tech University, 1977-08) Carr, Timothy RNot availableItem Conodonts from the Kinkaid Formation of the Illinois Basin(Texas Tech University, 1959-06) Burton, Robert CThe Kinkaid Formation is the uppermost unit in the Chester Series in the standard section for the Mississippian system in North America. The Kinkaid Formation crops out In the southwestern, southern, and southeastern margins of the Illinois Basin. The conodont fauna of the Kinkaid is distinctive, abundant, and varied. It can be correlated with the related conodont-ammonite zones in the Caney Shale In Oklahoma and, thereby, indirectly correlated with the Lower Namurian of Europe, which is differentiated on the basis of ammonites Detailed investigation of the Kinkaid conodont fauna suggests the following: 1. That the current move by the Illinois State Survey to establish a new member above the restricted Kinkaid formation is paleontologically sound, 2. That there v/as a restriction of the sea of Kinkaid time toward the vicinity of Johnson County, Illinois. 3. That there was a possible connecting seaway between the Illinois Basin and the Caney Shale area in the northern Arbuckles. The relatively greater abundance of conodonts recovered from limestone than from shale offers a clue to the paleoecology of conodont bearing creatures. This study establishes the Kinkaid conodont fauna in detail. New ranges are established for several forms. New species are described and Illustrated, occurrences noted, and faunal evaluations attempted.Item Crustal xenoliths from Potrillo Maar: implications for evolution of continental crust beneath the southern Rio Grande rift(Texas Tech University, 2003-08) Chattopadhyay, IndraniThe mid-crustal xenoliths from Potrillo maar record a petrologic and geochemical history that has until now been unknown from the Potrillo volcanic field. The igneous and meta-igneous xenoliths are samples of one or more plutonic bodies that crystallized at depths from 7-14 km (middle to upper crust). The rock unit ranges in composition from hornblende biotite diorite to quartz monzonite and monzogranite; it is broadly alkalicalcic The initial Sr87Sr86 suggests that the source region is heterogeneous or that the parental magmas were contaminated by crustal material. At least three geochemical groups can be identified, primarily on the basis of silica content. There is considerable overlap between groups 1 and 2, and the boundary between these two groups cannot be distinguished graphically. The third group is granitic and is geochemically distinct from groups 1 and 2. A dioritic composition is thought to represent mafic parental magma. Its calculated liquidus temperature at 2% H2O and 4 Mpa pressure is 1172°C. The presence of fossiliferous limestone xenoliths indicates that the Potrillo maar eruption sampled rocks of late Paleozoic age. However, the age of marble and quartzite xenoliths are not known. The quartzite xenoliths are relatively undeformed, but isoclinal folding in some of the marble xenoliths suggests subsurface deformation that has not been observed in local surface exposures of metasedimentary rocks. One model proposed for the crust under the southern Rio Grande rift assumes that the marble is late Paleozoic in age. The fossiliferous limestones are late Paleozoic in age and are older than the plutonic rocks. The relative age of the deformed marbles in this model is not clear, it can be deformed with the plutonic rocks or due to an earlier regional extensional event. In the second model, marble is proposed to result from contact metamorphism in the aureole of a plutonic rock body at a depth of 7-14 km. The presence of marble and calc-silicate xenoliths in dioritic blocks is consistent with a correlation of the marble with surface exposures of the Castner Marble in the Franklin MountainsItem Deposition, diagenesis and distribution of an "Upper Silurian" dolostone reservoir, RK Devonian Field(Texas Tech University, 1984-12) Young, Joe BrianThe RK Devonian Field was discovered in May 1975 with the completion of RK Petroleum Corporation's #1 G.T. Hall for an initial flowing potential of 455 BOPD on a 7/64" choke with a flowing tubing pressure of 1018#'s from five feet of perforations from 11,810-15' after treating with 250 gallons of acid. The well is located 660 feet from the north and west lines of Section 4, T&P RR. Co. Survey, Township 2-N, Block 37, Martin County, Texas. The field is situated in central Martin County (Fig. 1) approximately three miles north of the village of Tarzan and now includes all or parts of the following surveys and blocks: T&P RR. Survey, Township 2-N, Block 37, R.E. Montgomery Survey, Block A.Item Environmental framework and diagenesis of the Yates Formation, Apache Mountains, Culberson County, Texas(Texas Tech University, 1971-05) Zinz, Barry LynnNot availableItem Environments of deposition and diagenesis of the Upper Clear Fork Group, Yoakum County, Texas(Texas Tech University, 1987-08) Moore, Brian KeithThis project provides an Interpretation of the depositional environments, diagenesls, and resultant porosity relationships within the upper Clear Pork of Yoakum County, Texas. Of primary interest to this investigation Is the description of a small bryozoanalgal patch reef located at the base of the studied section. A discussion of the paleoecology, lateral variations, and community succession of the buildup also is given.Item Foraminiferal biostratigraphy and petrography of the Lower Pen Formation (Upper Cretaceous), Big Bend Region, Trans-Pecos Texas(Texas Tech University, 2003-12) Ashmore, Richard AllenIn the Big Bend region of Trans-Pecos Texas, Upper Cretaceous pelagic marine limestone of the Boquillas Formation is overlain by marine shale of the Pen Formation. This transition from predominately carbonate sedimentation to clastic sedimentation occurred diachronously across the interior of North America where it is recorded, for example, at the contact between the Niobrara Chalk and Pierre Shale and between the Austin Chalk and Taylor Marl. In the Big Bend region, this transition interval is sharply defined to the east but gradational to the west and consists of an interbedded series of thin pelagic limestone alternating with marl beds. The limestone beds are progressively thinner and more discontinuous upward within the sequence, and gradually pinch out to the west. Typically limestone beds vary from well-laminated foraminiferal wackestones to crudely laminated foraminiferal-ostreid-inoceramid packstones. Marl beds are texturally similar to the well-laminated foraminiferal wackestones, but contain substantial terrigenous clay in addition to microcrystalline calcite. Lamination within the limestone and marl beds is defined by foram-rich and foram-poor layers. The entire stratigraphic sequence is characterized by large shells and shell fragments of the "giant" inoceramid Cordiceramus sp., many of which are preserved as entire specimens in living position. The foraminiferal fauna is diverse, and consists primarily oi Gaudtyina {Siphogaudiyina) austiniana, Globigerinella aissana, Gyroidina depressa, G. globosa, Heterohelix reussi, Lenticulina rotulata, Marginotruncana coronata, and Rositafornicata. These taxa indicate that the Boquillas/Pen contact interval spans the Globotnmcana bulloides Assemblage Zone, composed of the Marginotruncana concavata Subzone and Globotnmcana fornicata Subzone, of Pessagno (1967), and is Santonian in age. The rhythmic alternation of limestone and marl possibly recorded wet-dry climate cycles driven by Milanko\ itch orbital variations that resulted in variable clastic sediment dilution and carbonate productivity, Inoceramid-produced biological effects surrounding inoceramid bioherms and/or irregularities in sea floor topography probably led to increased discontinuity of limestone relative to marl beds.Item Geology and petrology of Cretaceous and Tertiary granitic rocks, Lamoille Canyon, Ruby Mountains, Nevada(Texas Tech University, 1999-05) Lee, Sang-YunLamoille Canyon cuts through the northern Ruby Mountain metamorphic core complex and exposes the deep interior, which is characterized by highly metamorphosed miogeoclinal sedimentary rocks and various late Cretaceous and Tertiary granitic intrusions. Late Cretaceous granitic rocks in Lamoille Canyon can be broadly divided into two groups based on field relations: equigranular two-mica granitic gneiss and pegmatitic sillimanite-bearing two-mica granitic gneiss. The former rock unit is distinct in its higher concentrations of Fe, Mg, Na, Ca, Sr, V, Zr, Zn, Hf, but lower K, Rb, Th. In spite of these elemental differences, both of the late Cretaceous granitic units in this region are strongly peraluminous, have similar S^18 values, and are closely associated in the field. The origin of the pegmatitic two-mica granitic gneiss is best modeled by muscovite dominated dehydration melting of a metapelitic source, whereas the equigranular twomica granitic gneiss formed by plagioclase-imited biotite dehydration melting of a metapelitic source. Oligocene biotite monzogranite and related tonalitic dikes were emplaced in middle crustal levels (5-6 kbar). The biotite monzogranite suite consists of three geochemically distinct sub-groups. Group I shows characteristic geochemical features of A-type granite and is likely to have been generated by reaction of mantle-derived basaltic magma with either Archean orthogneiss or Proterozoic metapelite, leaving abundant plagioclase, orthopyroxene, and clinopyroxene as cumulative phases. Compared to group I, group II lacks characteristics of A-type granite. Partial melting of a metapelitic source explains most of the observed geochemical and stable isotopic data of group II. Geochemical variations within group I and group II can be explained by fractional crystallization but the possibility of minor crustal assimilation cannot be excluded. The compositions of tonalitic dikes are best explained by magma mixing between mantle derived (?) basaltic magma and granitic magma of the biotite monzogranite suite. Systematic geochemical comparison between the late Cretaceous and Oligocene granitic intrusions suggests temporal transition from early deep-seated crustal anatexis of a garnet-bearing source in a thickened crust, to later interaction between mantle-derived magma and crust, or high-temperature biotite-dehydration melting in a shallower crustal environment.Item Insoluble Residues of Certain Formations of West Texas(Texas Tech University, 1939-08) Abbott, Ralph ENot Available.Item Low grade metamorphic rocks of the Ruppert and Hobbs coasts of Marie Byrd Land, Antarctica(Texas Tech University, 1979-05) Brand, John FrederickLow grade metamorphic rocks exposed on the Ruppert Coast and Hobbs Coast are classified into two lithostratigraphic units. Herein the lower portion is named the Wilkins Nunatak Group and the upper portion is termed the Mount Pearson Group. The Wilkins Nunatak Group consists of a basal sequence of carbonate rocks conformably overlain by continental sediments. The Mount Pearson Group is composed of geosynclinal graywackes and subgraywackes. During the late Precambrian and early Paleozoic a shallow epicontinental sea covered the Ruppert and Hobbs coasts. Shelf carbonate beds which form the basal portion of the Wilkins Nijinatak Group were deposited upon an eroded complex of amphibolite gneiss. As the Ruppert Coast and areas farther west were uplifted, the sea retreated eastward and subgraywackes, protoquartzites and arkose conglomerates were deposited, with seeming conformity, upon the carbonate banks. Basinward, the continental sediments graded into thin-bedded sequences of sandstone and shale. By the Ordovician Period, the entire area was emergent and was subjected to widespread erosion which formed the regional unconformity at the top of the Wilkins funatak Group. Subsequently, areas west of the Ruppert Coast were uplifted and lithic graywackes, feldspathic graywackes and subgraywackes of the Mount Pearson Group accumulated in a rapidly subsiding basin. As subsidence continued, possibly to depths approaching 10 kilometers, the basal portion of the Wilkins Nunatak Group was metamorphosed. Granite plutons were emplaced during the Cretaceous Period. Block faulting occurred during early Tertiary time,Item Magmatism associated with extension, Harrison Pass Pluton, Ruby Mountains, Nevada(Texas Tech University, 1996-08) Burling, Trina CelesteThe objectives of this study are: (1) to describe in detail the Tertiary rock units exposed in the Harrison Pass pluton, (2) to use geochemical and isotopic data to constrain the petrogenesis of Tertiary granitic rocks in this extensional setting, (3) to develop a possible model of emplacement for the Harrison Pass pluton, and (4) to integrate the information gathered in this study of the Harrison Pass pluton for comparison with previous studies in order to gain a better understanding of Tertiary granitic magmatism in the Basin and Range province and how it relates to lithospheric extension and development of metamorphic core complexes.