The nose of the Eastern shelf of the Midland Basin is a prominent structural and depositional feature present in Glasscock, Sterling, and Howard counties, Texas. This feature has been expressed in many regional maps and mentioned in some literature, but has not otherwise been studied significantly. This study looks at the viability of using an acoustic impedance seismic inversion to interpret the 2nd and 3rd order sequence stratigraphy of the southern portion of the nose of the Eastern shelf along with its shelf to basin transition in Glasscock, Sterling, and Reagan counties during the Wolfcampian (Asselian-Sakmarian) time (Early Permian). The Wolfcamp Formation (Wolfcampian-Leonardian) was subdivided into six units based on regionally mapped shale markers that correlate with 3rd order sequence boundaries. These horizons were mapped throughout the study area utilizing 3D seismic data and well logs. Analysis of seismic amplitude and inversion (acoustic impedance) volumes, along with well logs were then used to create a 2nd and 3rd order sequence stratigraphic framework in the study area. Six 3rd order sequences and two 2nd order sequences were identified in the study area during the Wolfcampian. From this framework a 2nd order sea-level curve was developed. The oldest Wolfcampian 3rd order sequence is marked by sediment bypass of the shelf and slope into the basin during a 3rd order sea level fall. Shelfal deposition resumed during subsequent sequences as sea-level rose and carbonate production resumed. Carbonate production increased during sequences four through six as part of a 2nd order sea-level highstand. During this highstand the nose of the Eastern shelf grew vertically increasing the gradient of the slope from less than 1° to 3.5°. The end of Wolfcampian deposition is marked by a large number of gravity flows into the basin resulting from subaerial exposure and erosion after a second order sea-level fall.

The Jurassic Twist Gulch Formation of central Utah was deposited in the active Arapien sub-basin of the Western Cordillera foreland trough. We herein demonstrate the utility of integrating facies analysis, terrestrial sequence stratigraphy, and detrital zircon (U-Pb) ages to improve paleogeographic reconstructions as well as identify regional unconformities, locate fluvial depocenters, and infer sediment supply/accommodation space ratios. Strata of the Twist Gulch Formation in Pigeon Creek Canyon (PCC) near Levan, Utah consists primarily of alluvial deposits, while in Salina Canyon (SC) the Twist Gulch Formation is comprised of a mix of alluvial and marginal marine deposits associated with the Jurassic Western Interior Seaway. Within the PCC section, a change from high accommodation system (HAS) mudstones to low accommodation system (LAS) multi-storied channel sandstones and back to HAS deposits exists. This same pattern exists in the SC section but culminates with marine deposits. Terrestrial sequence stratigraphy predicts that the change from HAS to LAS deposits indicate a sequence boundary and thus an unconformity. The J-3 unconformity, a regional unconformity on the Colorado Plateau, separates strata of Callovian age from Oxfordian age in Utah. Using detrital zircons (U-Pb), the first radiometric ages were obtained for the Twist Gulch Formation. The J-3 unconformity is bracketed by detrital zircon (U-Pb) ages and stratigraphic relationships in the study area. These new ages suggest that the Twist Gulch Formation is time-equivalent to the Entrada Sandstone, Curtis, and Summerville formations of the Colorado Plateau. Further, integrating facies analysis, terrestrial sequence stratigraphy, and detrital zircon (U-Pb) ages predicts that the PCC section was an active depocenter during the early Oxfordian in which sedimentation outpaced accommodation space, prograding the Oxfordian shoreline of the Jurassic Western Interior Seaway shoreline eastward. This integration process also predicts that subsurface sandstones positioned above the J-3 unconformity on the west side of the Wasatch Plateau are of a different age, depositional system, and systems tract from subsurface sandstones on the east side of the Wasatch Plateau.

Lower Pennsylvanian, coal-bearing, siliciclastic strata of the central Appalachian foreland basin were deposited in continental to marginal marine environments influenced by high-amplitude relative sea level fluctuations. Sediment was derived from both the low-grade metamorphic terrain of the emergent Alleghanian orogen towards the southeast, and the cratonic Archean Superior Province in the north. Immature sediments derived proximally from the Alleghanian orogen, including sublithic sandstone bodies, were deposited as a southeasterly-thickening clastic wedge within a southeast-northwest oriented transverse drainage system. Texturally and mineralogically mature quartzarenites were deposited in strike-parallel elongate belts along the western periphery of the basin. These mature quartzarenites are braided fluvial in origin and were deposited within northeast-southwest oriented axial drainage head-watered in a northerly cratonic source area. The contemporaneity of transverse and axial fluvial systems defines a trunk--tributary drainage system operating in the central Appalachian foreland basin during the early Pennsylvanian. Detailed analysis of core, gamma ray logs, and cross-sections reveals a hierarchy of bounding discontinuities and architectural elements within the study interval. Discontinuities are both erosional and depositional (condensed) surfaces of interpreted 3rd-order (~ 2.5 Ma) and 4th-order (~ 400 k.y.) origin. Architectural elements within 4th-order sequences consist of upward-fining lowstand and transgressive incised valley fill, alluvial, and estuarine deposits, and upward-coarsening highstand deltaic deposits that are separated by condensed sections. 4th-order sequences are stacked into 3rd-order composite sequences. Sequence stratigraphic architecture in the central Appalachian basin can therefore be attributed to 4th-order Milankovitch orbital eccentricity cycles superimposed on 3rd-order orogenically driven subsidence, or more likely, 4th-order Milankovitch orbital eccentricity cycles superimposed on a lower-frequency eccentricity cycle. The widespread nature of both 3rd- and 4th-order marine flooding zones and sequence boundaries enables both genetic and depositional sequence stratigraphy to be applied to terrigenous to marginal marine coal-bearing strata of the central Appalachian basin. Regionally extensive coal beds occur in close association with both 4th-order condensed sections as well as within highstand deltaic deposits. Formation of coal beds in the central Appalachian basin of southwest Virginia is therefore attributed to both an allocyclic glacio-eustatic mechanism, associated with Milankovitch orbital eccentricity cycles, and autocyclic deltaic processes related to channel avulsion and delta lobe switching. / Master of Science

Lower Pennsylvanian siliciclastic sedimentary rocks of the central Appalachian Basin consist predominantly of nonmarine, coal-bearing facies that developed within a fluvio-estuarine, trunk-tributary drainage system in a foreland-basin setting. Sheet-like, sandstone-mudstone bodies (up to 100 km wide and 70 m thick) developed in an axial trunk drainage system, whereas channel-like, sandstone-mudstone bodies (up to several km wide and 30 m thick) developed in tributaries oriented transverse to the thrust front. The origin of these strata has been debated largely because the paleogeomorphology and facies architecture of the New River Formation (NRF) are poorly understood. A sequence stratigraphic framework for the NRF, based on a combination of outcrop mapping and subsurface well-log analysis, reveals: 1) regionally significant erosional surfaces along the bases of sheet-like and channel-like sandstone bodies (sequence-boundaries), 2) fluvial- to estuarine-facies transitions (marine flooding surfaces), 3) erosionally based, framework-supported, quartz-pebble conglomerates (ravinement beds), and 4) regionally traceable, coarsening-upward intervals of strata (highstand deposits above maximum flooding surfaces). Using these criteria, both 3rd- and 4th-order sequences have been identified. An idealized 4th-order sequence consists of deeply incised, fluvial channel sandstone separated from overlying tidally modified estuarine sandstone and mudrock by a ravinement bed, and capped by coarsening-upward bayhead delta facies. The relative thickness of fluvial versus estuarine facies within a fourth-order sequence reflects a balance between accommodation and sediment supply within a 3rd-order relative sea level cycle. Lowermost 4th-order sequences are dominated by fluvial facies, whereas the uppermost sequences are dominated by estuarine facies. Therefore, 3rd-order sequence boundaries are interpreted to lie at the bases of the lowermost, fluvial-dominated fourth-order sequences. Coarsening-upward intervals that record the maximum landward extent of marine conditions are interpreted as highstand deposits of the composite third order sequence. Thus, the NRF consists of thick, superimposed fluvial sandstone of the lowstand systems tracts and anomalously thin transgressive and highstand systems tracts. Asymmetrical subsidence within the foreland basin resulted in westward amalgamation of multiple, 4th-order, fluvial valley-fill successions and sequence boundaries. The Early Pennsylvanian time period was characterized by global icehouse conditions and the tectonic assembly of Pangea. These events affected the geometry of the overall stratigraphic package, which can be attributed to high-magnitude, high-frequency, glacioeustatic sea-level fluctuations superimposed on asymmetric tectonic subsidence. / Master of Science

Carbon dioxide sequestration in coal-bed methane fields has potential to add significant recoverable reserves and extend the production life of coal-bed methane fields while at the same time providing a geologic sink for atmospheric greenhouse gases. The ability to relate the thickness, extent, and quality of coal seams to their relative position within a sequence is fundamental in determining the sequestration potential of a geologic formation. This thesis documents the carbon dioxide storage capacity and enhanced coalbed methane recovery of lower Pennsylvanian coal-bearing siliciclastic strata within the Bradshaw CBM field, southern McDowell County, WV. Analysis of outcrop, gamma ray and density logs, and eight cross-sections within the study area reveals a hierarchy of bounding discontinuities and architectural elements. Discontinuities are both erosional (unconformable) and depositional (condensed) surfaces of 3rd-order (~2.5 Ma) and 4th-order (~400 k.y.) origin. Architectural elements bound by 4th-order erosional discontinuities consist of upward-fining lowstand and transgressive incised valley fill, alluvial, and estuarine deposits, and upward-coarsening highstand deltaic deposits, representing 4th-order sequences. 4th-order sequences are stacked into composite 3rd-order sequences. Sequence development is attributed to higher frequency (~400 k.y.) 4th-order Milankovitch orbital eccentricity cycles superimposed on lower frequence (~2.5 Ma) orbital eccentricity cycles. Coal seams occur in the transgressive and highstand systems tracts, associated with 4th-order flooding surfaces and high-frequency deltaic autocycles, respectively. Transgressive coal-bed development is attributed to Milankovitch driven glacio-eustacy while highstand coal-bed development is attributed to autocyclic deltaic influences. Assessment of carbon dioxide storage capacity within coals of the lower Pennsylvanian Pocahontas and Bottom Creek formations in the Bradshaw CBM field indicates that 19 million tons of carbon dioxide can be sequestered. Sequestration of carbon dioxide within the Bradshaw CBM field has the potential to increase coal-bed methane recovery by as much as 52 billion cubic feet. / Master of Science

The lower Pennsylvanian, coal-bearing, siliciclastic strata in Dickenson/Wise counties of southwest Virginia were deposited in continental to marginal marine environments influenced by high-amplitude relative sea level fluctuations. Coal-bearing siliciclastics of the eastern facies belt are fluvio-deltaic in origin, with sediment derived from the erosion of low-grade metamorphic and Grenvillian-Avalonian terranes of the Alleghanian orogen to the southeast. Elongate NNE trending quartzarenite belts in the northwestern region of the basin are braided-fluvial deposits and were sourced by the cratonic Archean Superior Province to the north. This orthogonal relationship between the southeastern coal-bearing siliciclastics and the northwestern quartzarenites reflect a trunk-tributary drainage system operating during the lower Pennsylvanian in the central Appalachian basin. Analysis of core, gamma ray and density logs, and six cross-sections within an approximately 20 km² study area reveals a hierarchy of bounding discontinuities and architectural elements. Discontinuities are both erosional (unconformable) and depositional (condensed) and are 3rd-order (~ 2.5 Ma) and 4th-order (~ 400 k.y.) in origin. Architectural elements are bound by 4th-order discontinuities and consist of upward-fining lowstand and transgressive incised valley fill, alluvial, and estuarine deposits, and upward-coarsening highstand deltaic deposits and represent 4th-order sequences. Lowstand and transgressive deposits are separated from the highstand deposits by marine flooding zones (condensed sections). 4th-order sequences are stacked into composite 3rd-order sequences. Sequence development can be attributed to 4th-order Milankovitch orbital eccentricity cycles superimposed on a lower-frequency eccentricity cycle. Extensive coals occur in both transgressive and highstand systems tracts. Coals within the transgressive systems tract are associated with 4th-order flooding surfaces, while coals within the highstand systems tract occur within high-frequency deltaic autocycles. Therefore, coals formation in the central Appalachian basin can be attributed to be of both allocyclic (glacio-eustacy) and autocyclic (deltaic processes) mechanisms. / Master of Science

<p> The Middle Devonian Dundee Limestones of Southwestern Ontario accumulated in the Michigan and Appalachian Basins, with deposition in part being controlled by the proximity to the Findlay and Algonquin arches. Six lithofacies were recognized in the Dundee Formation during detailed core and outcrop studies . Stratigraphic relations indicate that, prior to deposition of Dundee carbonates, a major regression exposed underlying Detroit River sediments adjacent to the arches. Subsequent transgression deposited reworked sands and shallow shelf, bioclastic limestones in most areas of the adjoining basins while in westernmost regions of the Appalachian Basin Columbus Formation sediments were accumulating adjacent to the Findlay Arch. </p> <p> Transgression became interrupted during middle Dundee time and a thick unit of lagoonal muds was deposited in the Appalachian Basin. A regionally well-developed firmground capping these mudstones indicates that a significant episode of non-deposition ensued. The equivalents of these muds in the Michigan Basin are pulses of coarse, reworked grainstones and rudstones indicating that substrates there were shallower and above wave base. Evidence of subsequent renewed transgression is preserved as middle to outer shelf moderately fossiliferous mudstones and wackestones overlying shallow shelf facies. </p> <p> Many friends, too many to mention here, made my stay at McMaster an enjoyable one. Mac wouldn't have been the same without the numerous challenges and imaginative adventures in which these people were always willing to participate. Francois Brissette, Bruce Willmer, Randy Meecham, Stu Miller, Steve Beneteau and other members of the Rockbusters Football and Aureoles Baseball teams provided continuous entertainment both on and off of the sports field. Their dedication and light-hearted approach allowed me to maintain a respectable degree of sanity throughout my studies. </p> <p> Finally, I would like to thank my family for their continual assistance, encouragement and support provided during the pursuit of my academic endeavours. </p> / Thesis / Master of Science (MSc)

<p> The Lower Cretaceous (Albian) Viking Formation at Harmattan East and Crossfield, Alberta, contains two regionally extensive erosion surfaces, VE3 and VE4, separating three allomembers, A-B, D and E. These erosion surfaces can be mapped over large areas of the Alberta basin allowing for the creation of a Viking allostratigraphy. </p> <p> The allostratigraphic base of the Viking alloformation in the study area is informally designated BV. The BV log marker is overlain by allomember A-B, which in turn is overlain by the regionally extensive ravinement surface VE3. The VE3 surface is sharply overlain by allomember D, a northeastward thinning clastic wedge composed of storm dominated facies and nonmarine deposits. Allomember D is in turn overlain by the regionally extensive ravinement surface VE4. Allomember E, which overlies this unconformity is a complex succession of coarse grained facies interbedded with dark mudstones. The upper . part of allomember E is composed of dark mudstones bounded at the top by a regionally extensive condensed section (Base of Fish Scales) that informally marks the allostratigraphic top of the Viking alloformation in the study area. </p> <p> Viking sedimentation began with the deposition of basinal and offshore transitional mudstones, siltstones and sandstones of allomember A-B. A major drop in sea level allowed valleys to incise into these sediments. Nonmarine and upper shoreface deposits of allomember A-B were eroded at Harmattan East during the ensuing transgression that produced the VE3 ravinement surface. A second relative sea level lowering resulted in northeastward progradation of allomember D. Renewed transgression modified the older subaerial erosion surface on top of allomember D, forming the marine ravinement surface VE4 and the overlying deposits of allomember E. Multiple stillstands or slow rates of transgression produced the "steplike" southwestward climbing morphology on the VE4 surface. Fluvial systems supplied coarse sediment to each shoreface incision ("step"). During minor sea level falls, storm and tidal currents reworked sediment at these shorefaces and also transported sediment basinward over older "stepped" shorelines forming onlap markers EO to E5. Continued transgression blanketed the coarse grained interbeds with offshore dark mudstones (Colorado Shale). A major pause in basin deposition led to the formation of a condensed section of fish skeletal remains (Base of Fish Scales). The base of this unit marks the end of Viking depostion in the study area. </p> <p> The Harmattan East Viking oil field is producing from the coarse grained transgressive lag that overlies VE4. It is separated from Caroline field (along depositional strike) by a rise in the VE4 surface. </p> / Thesis / Master of Science (MSc)

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