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

An enhanced coal-bed methane facility in Russell County, Virginia is targeting lower Pennsylvanian coals for CO2 storage, but the shallow sandstone units intercalated with the coals may also prove to be potential CO2 reservoirs, since the injection apparatus is already in place. Using samples from a continuous core in southwestern Virginia, this detailed review of the petrography and local volume of the Breathitt Formation sandstone units examines their diagenetic alterations in order to assess the units' reservoir quality. The high-frequency sequences of immature sandstones, heterolithics, shales and coals in Russell County represent deposits from the transverse fluvial facies association of a broad braided-fluvial drainage system in the central Appalachian Basin. The sandstone units within these sequences are laterally extensive, maintaining similar thickness and gamma ray signature across the study area. Lower Pennsylvanian sandstone units are consistently sublitharenite with a diagenetic mineral assemblage including siderite, chlorite, kaolinite, albite, illite, silica and calcite. Primary porosity is not preserved, but secondary porosity (5 ± 3.1 %) has developed at the expense of feldspars and unstable lithic fragments. Permeability assessments collected in Grimm (2010) measured impervious values (0.005-0.008mD) for the medium-coarse grained sublitharenites. At the temperatures and pressures present within these units, CO₂ is unlikely to react with either the primary or diagenetic mineralogy in a way that negatively impacts continued injection on human time scales. Low pore volume and permeability due to the timing of certain authigenic mineral emplacement are the main hindrance to reservoir quality. Lower Pennsylvanian sandstones are not viable potential reservoirs for carbon sequestration. / 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

The Early Pennsylvanian (Bashkirian/Morrowan) Round Valley Limestone of northeastern Utah was deposited on the Wyoming shelf, a slowly subsiding depositional surface located between the Eagle and Oquirrh basins. The 311-foot-thick Round Valley Limestone displays a distinct cyclicity formed by stacked, meter-scale parasequences, comprised of a limited suite of open- to restricted-marine limestones with minor interbeds of siltstone and shale. Open-marine deposits are characterized by mudstone and heterozoan wackestone-packstone microfacies (MF1-4) and comprise the lower portions of parasequences. Rocks of these microfacies were deposited during maximum high-order transgression of the shelf. As sediment filled the limited accommodation, the shelf became restricted, leading to deposition of mollusk-peloid dominated wackestone microfacies (MF6). Grainstones (MF5) microfacies are volumetrically limited in the Round Valley and represent deposition on isolated sand shoals that populated the shallow shelf. The complete Round Valley section at Split Mountain in Dinosaur National Monument is comprised of 5 intermediate-order sequences and 48 higher-order parasquences. Twenty-one of the shallowing-upward cycles are bounded by exposure surfaces as indicated by the occurrence of rhizoliths, glaebules, autobreccia and alveolar structures. Four of these that also indicate a significant drop in sea level (abnormal subaerial exposure surfaces and surfaces with erosional relief) constitute candidate sequence boundaries. The high percentage of cycles capped by exposure surfaces indicates that deposition of the Round Valley took place intermittently and that the Wyoming shelf was exposed during a significant portion of the Bashkirian epoch. Intermittency of deposition is confirmed by comparing the thickness and sequence architecture of the Round Valley Limestone with coeval strata in the eastern Oquirrh basin (Bridal Veil Limestone). The Bridal Veil Limestone is four times thicker and contains 24 cycles not represented on the Wyoming shelf.

The Black Prince Limestone of southeastern Arizona has been assigned to the Morrowan on the basis of several long-ranging fossils. Since these were not especially diagnostic, the exact time represented by the Black Prince within the Morrowan was uncertain. To date the Black Prince more precisely, six sections were systematically sampled for conodonts. The condonts found, especially Neognathodus bassleri, Rachistognathus muricatus, Idiognathoides convexus, and Spathoqnathodus coloradoensis, indicate a middle Morrowan to early Derryan age for the Black Prince in the study area. Four conodont zones can be recognized: the Neognathodus bassleri Zone, the Idiognathodus sinuosis.- Streptognathodus anteeccentricus Zone , the Idiognathoides convexus Zone, and the Spathognathodus coloradoensis-Neognathodus columbiensis Zone. These zones compare favorably with the zonation previously established in the type Morrowan. This biostratigraphic evidence suggests that the hiatus between the Black Prince and Horquilla Limestones increases in magnitude from southeastern to south-central Arizona. The Black Prince represents a sequence of tidal flat and shallow subtidal carbonate deposits. Mudstones and sparsely fossiliferous wackestones with low fossil diversity and abundance characterize the tidal-flat facies. Grainstones, packstones, and fossiliferous wackestones with high fossil diversity and abundance characterize the shallow subtidal facies.