The diploma thesis studies lithofacies and cyclic pattern of about 200 m thick upper part of the Poruba Member (Serpukhovian) in the Karviná area of the Ostrava-Karviná coalfield. The objective of this thesis is to identify laterally persistent cycles from the local ones by the set of cross-sections and to better understand their formation, especially the role of glacio- eustatic sea level changes. Set of cross-sections constructed from boreholes were used for this study. The three genetic cycles were identified in the thesis based on previous studies of Gastaldo et al. (2009). From base to top the cycles are the (i) Max, (ii) Otakar a (iii) Gaebler. Their thickness fluctuates between 19.9 and 109.9 meters. The genetic cycles are bounded, with one exception, by a transgressive erosional surface of important faunal marine bands. From the set of cross-sections and maps of thickness and sand content (%), constructed for individual genetic cycles, it is obvious that the area of maximum thickness corresponds to area of increased content of medium- and coarse-grained sandstone. Maxima of sand content and thicknesses follow NNE-SSW direction, which is in agreement with basin axis. These maxima are interpreted as areas occupied by fluvial channels that are responsible for deposition of coarse- grained...

A mineração subterrânea na região carbonífera de Santa Catarina possui forte controle estrutural. A área de pesquisa da Mina D situa-se na porção NE do município de Araranguá. Este trabalho definiu o comportamento estrutural das rochas sedimentares e da camada de carvão Barro Branco na área de pesquisa através da avaliação integrada de imagens de satélite e dados de 100 furos de sondagem. As principais direções dos lineamentos identificadas nas imagens de satélite são N30º-60ºW, N60º-80ºE e N30º-60ºE. O mapa de contorno estrutural da camada de carvão e as seções geológicas mostram que a área é afetada por falhas normais de direção N30°-60°W, N50°-70°E, N10°-20°W e E-W. As falhas normais de direção NE apresentam extensão regional e exercem significativa influência no arranjo estrutural da área. Nesses casos os rejeitos são expressivos (>100 metros) e inviabilizam a recuperação econômica do carvão em algumas porções da área. A orientação das galerias deve ser de modo paralelo a estas falhas nas suas proximidades. As falhas normais de direção NW são as mais frequentes e possuem extensão e rejeitos menores (<30 metros). O planejamento da lavra deve considerar esse sistema de falhas, evitando o cruzamento das mesmas. As falhas normais de direção N-S foram identificadas na área e apresentam rejeitos expressivos (>70 metros). Ocorrem ainda falhas inversas associadas ao soerguimento ocasionado por intrusões de diabásio. Próximo a estas áreas podem ocorrer zonas de acúmulo de tensões, geralmente associadas a problemas de instabilidade de teto e levantamento de piso. A metodologia aplicada demonstrou ser eficiente na determinação prévia das estruturas tectônicas e na avaliação preliminar da sua influência na mineração subterrânea de carvão. / The underground coal mining in the carboniferous region of Santa Catarina state has a great structural control. The Mina D research area is located in the NE portion of the Araranguá city. This study has defined the structural bearing of the sedimentary rocks and the Barro Branco coal seam in the research area through the integrated evaluation of satellite images and 100 boreholes data. The major lineaments identified in the satellite images have N30º-60ºW, N60º-80ºE and N30º-60ºE directions. The coal seam structural contour map and the geological sections presents that the area is affected by normal faults which have N30°- 60°W, N50°-70°E, N10°-20°W and E-W directions. The NE direction normal faults have regional extension and are the most influent in the structural arrangement of the area. This faults have expressive tailings (>100 meters) and prevent the economic recover of the coal in some portions of the area. The galleries should be oriented parallel to it. The normal faults with NW direction is the most frequent and have minor extension and tailings (<30 meters). The mining plan should consider it in order to avoid have to cross it. The N-S direction normal faults were identified in the area and presents expressive tailings (>70 meters). Inverse faults occur associated with the uplift related to diabase sills intrusion. Close to this area may occur stress accumulation zones usually related to roof instability and floor heaving problems. The applied methods proved to be efficient in the determination of tectonic structures and in the preliminary evaluation of their influence on underground coal mining.

No description available.

Integrated sequence stratigraphy and geochemistry has significantly improved our knowledge of the formation and distribution of early and late diagenetic products in North American Mississippian carbonates. Deposition of the Madison Limestone occurred in concert with a major perturbation to the global C-pool, the timing of which was constrained by comparing secular variations in the delta13C values from the Madison Limestone with limited biostratigraphy. These early constraints were then improved by peak matching of 87Sr/86Sr values from this study with European brachiopod 87Sr/86Sr. The secular variations in the delta13C values were then applied as a chronostratigraphic tool to outcrops and subsurface core. As a result, our sequence stratigraphic interpretations and knowledge regarding lateral facies variability in carbonate rocks is significantly improved. Geographic variability in the magnitude of the delta13C values is also documented along the dip-transects which suggests that marine waters experienced increasing restriction in a landward direction. These results show how local changes to the C-pool are controlled by the morphology of the depositional system which can significantly affect the original signal of the global carbon pool. The geographic variability in the delta13C and delta18O values from reservoir quality dolomites along the mid-to-upper Madison ramp suggest they also precipitated from a restricted water mass with increased salinity, temperature and alkalinity which in turn, were responsible for the distribution of massive quantities of strataform dolomite deposited during the continental transgression at the beginning of the Mississippian. Trace element and 87Sr/86Sr values from strataform dolomite suggest initial formation from Mississippian seawater and slight resetting during shallow burial diagenesis. Petrography indicates that the formation of this dolomite ceased in the shallow burial environment, between the Mississippian and Permian. These dolomites are cross-cut by comparatively small volumes of geothermal-hydrothermal dolomite associated with Laramide-age breccias and fractures. Tectonic-hydrothermal activity associated with the Laramide Orogeny was responsible for late stage calcite cemented fractures and breccias which cross-cut all carbonate rocks discussed in this thesis. Radiogenic 87Sr/86Sr, depleted delta18O and enriched delta13C values and the hottest fluid inclusions measured in this study suggest the late stage calcite formed in the hydrothermal environment and under the most open-system and water-dominated conditions. Tectonic-diagenesis is ultimately responsible for establishing vertical barriers in the otherwise porous and permeable strataform dolomites.

Conodonts are important biostratigraphic tools for the delineation and calibration of the geochronological boundaries within the Carboniferous and used generally as stage-boundary markers for the Lower Carboniferous (Mississippian). The studied successions in the Central and Eastern Taurides were mainly deposited in a shallow marine environment during the Carboniferous time and they comprise less abundant and diversified conodont fauna. The conodont fauna represented by twenty-four species belonging to ten genera have been described from the studied sections (AS / AAO / BSE and HB) in the Taurides (Turkey). Regarding the first occurrences and last occurrences of biostratigraphically significant species within these sections, the following zones have been established across the Lower Carboniferous successions: (1) Polygnathus inornatus Zone (Hastarian-Lower Tournaisian) / (2) Gnathodus cuneiformis &ndash / Polygnathus communis communis Zone (Ivorian-Upper Tournaisian) / (3) Polygnathus mehli mehli Zone (Ivorian-Upper Tournaisian) / (4) Gnathodus girtyi girtyi Zone (Brigantian-Upper Visean) / (5) Gnathodus girtyi simplex Zone (Pendelian-Lower Serpukhovian) / (6) Rhachistognathus muricatus Zone (Zapaltyubinsky-Upper Serpukhovian) and (7) Declinognathodus inaequalis - Declinognathodus noduliferus Zone (Bogdanovsky-Lower Bashkirian). Based on the recovered conodont assemblages, Visean - Serpukhovian boundary has been recognized by the first occurrence of Gnathodus girtyi simplex and the Mid-Carboniferous boundary is delineated by the first occurrence of Declinognathodus inaequalis, which is an index taxon for the basal part of the Bashkirian. Based on the microfacies studies it can be concluded that conodont elements essentially obtained from the crinoidal bioclastic packstone-grainstone, crinoidal packstone-grainstone, coated bioclastic grainstone, intraclastic grainstone and spiculite packstone facies in the studied sections. It can be concluded that that the occurrence of abundant crinoids are indicative criteria for the presence of conodonts. Additionally, geometric morphometric analyses of biostratigraphically important genus, Gnathodus, on the basis of data available in the literature emphasize the importance of numerical taxonomy and reveal that taxonomic revision of this genus is needed.

Earth is characterized by episodes of glaciations and periods of minimal or no ice through geologic time. Using the linear energy balance model (EBM), nonlinear EBM with empirical ice sheet schemes, the general circulation model coupled with an ice sheet model, this study investigates the occurrence and stability of glaciations in geologic time. The simulations since the last glacial maximum (LGM) suggest that the summertime thawline of ice sheets conforms closely to the equatorward edge of the ice sheets and implies the relative stability toward deglaciation. CO2 levels are indispensable in controlling the initiation of ice sheet in the Cretaceous. At low CO2 levels, ice sheets exist in all periods no matter LGM or the last interglacial (LIG) orbital elements; however, at high CO2 levels ice sheets rarely exist. The simulations agree well with recent geological evidence of the hysteresis of glaciations in the Permo-Carboniferous. Gondwanaland reached its glacial maximum when CO2 level was roughly the same or slightly higher than the preindustrial value. With a further increase of CO2, deglaciation dominates and results in an ice free state. Again, if CO2 decreased to the present level, Gondwanaland would be glaciated once more and start a new cycle of glaciation and deglaciation. Simulations from five paleogeography maps in Gondwanaland with a suite of CO2 levels and different orbital elements reveal that paleogeography, CO2 levels and the Milankovitch cycles all contribute to the glaciations of Gondwanaland. This study shows that orbital elements alone are insufficient to account for the evolution of ice sheets. Net radiative forcing caused by greenhouse gases, such as CO2 and solar constant change are the primary drivers to glacial inception or demise. Continental geography, CO2 levels, solar constant change, and the Milankovitch cycles complicate the glacial history of Earth.

Nearly 550 samples of fine grained carbonates, collected every 0.5 to 1.0 m from the Bloom Member of the Snaky Canyon Formation at Gallagher Peak, Idaho, were analyzed to determine the high-resolution carbon isotope stratigraphy. To constrain for diagenesis, thin sections were petrographically analyzed and viewed using cathodoluminescence microscopy. Chemical analyses were performed using an electron microprobe. Average delta18O and delta13C values from the Bloom Member are -4.5% +/- 1.6% (1 sigma) and 2.1% +/- 1.1%, respectively. Maximum delta13C values are about 1% higher for the Desmoinesian and Missourian than the Morrowan and Atokan, similar to results from the Yukon Territory. delta18O and delta13C values are lowest for crystalline mosaic limestones and siltstones, moderate for packstones, wackestones, and mudstones, and highest for boundstones and grainstones. The delta13C profile from Gallagher Peak consists of high frequency 1% oscillations with several larger excursions. No large delta13C increase at the base of the section suggests the Mid-Carboniferous boundary is in the underlying Bluebird Mountain formation. delta13C of Gallagher Peak and Arrow Canyon, NV, correlate well from 318 to 310 Ma, but correlation becomes more difficult around 310 Ma. This may result from increased restriction of the Snaky Canyon platform beginning in the Desmoinesian. Most of the short term (<1 Ma) isotopic excursions are the result of diagenesis. Two of the largest negative excursions at Gallagher Peak correlate with two large negative excursions at Big Hatchet Peak, NM, possibly due to sea level lowstands of the Desmoinesian. Phylloid algal mounds at Gallagher Peak are associated with positive excursions because of original aragonite composition and increased open marine influence. Positive excursions related to other facies characteristics also result from increased marine influence. The delta13C curve for the upper half of Gallagher Peak contains three repeated cycles of increasing delta13C over 1-1.5 Ma, which are possibly related to long-term sea level fluctuations. Given the complexity of each local environment, without detailed biostratigraphy, detailed rock descriptions, and analysis of the various rock components, delta13C stratigraphy of whole rocks can be misinterpreted.

The purpose of this study is to investigate the Upper Tournaisian substage within the Carboniferous carbonate deposits of the Aladag Unit in the Hadim region (Central Taurides) based on foraminiferal diversity and to study the meter scale cyclicity in order to explain the sequence stratigraphic evolution of the carbonate succession. In this study, a 27.01 m thick stratigraphic section consisting of limestones and shales was measured and 89 samples, collected along this section, were analyzed. Micropaleontological analyses are based on benthic foraminifera. According to the benthic foraminiferal assemblages, two biozones were identified as Zone Ut1 and Zone Ut2 within the Upper Tournaisian. Zone Ut1 is characterized by a poor foraminiferal assemblage while the Zone Ut2 consists of a diverse Upper Tournaisian foraminiferal fauna. In order to construct a sequence stratigraphic framework and appreciate depositional environmental changes, microfacies studies were carried out. Seven microfacies types were recognized and depending on the stacking patterns of these microfacies types, two fundamental types of cycles, A and B, were identified. Through the measured section, twenty-five shallowing-upward meter scale cycles and two sequence boundaries were determined. Quantitative analysis of benthic foraminifera was used to demonstrate the biological response to cyclicity. Since foraminifers are very sensitive to sea level changes, the abundance of benthic foraminifera displays a good response to sedimentary cyclicity. In order to apply a worldwide sequence stratigraphic correlation, the sequence boundaries and the meter scale cycles of this study were compared with those described in South China and Western European platform and the Moscow Syneclise. An Early Tournaisian transgression was followed by a major fall in relative sea level during the Late Tournaisian. Two sequence boundaries recognized in the measured section correspond to global sea level falls in the Late Tournaisian.

The Lysorophia is an order of small, but extremely elongate and tiny-limbed aquatic lepospondyl amphibians existing from the Middle Pennsylvanian through the Lower Permian, primarily in North America. The order comprises one family, Cocytinidae, with three recognized species: Brachydectes newberryi (=Cocytinus gyrinoides), B. elongatus (=Lysorophus tricarinatus, partim) and Pleuroptyx clavatus. Other named species are considered Lysorophia, incertae sedis. Lysorophoids are distinguished by their fenestrated skulls, anteriorly sloping suspensoria, short mandibles (each bearing a lateral mandibular fenestra) and by extensive, well-ossified hyobranchial skeletons. Presacral vertebrae are holospondylous and number between 69 (B. newberryi) and 97 (B. elongatus). Neural arch halves are sutured at their midlines and to their centra. Aspects of lysorophoid anatomy, including the hyobranchial skeleton, suggest that the lysorophoids are neotenic. / While closely similar to one another, lysorophoid species are highly derived relative to other Paleozoic amphibians. They are most closely related to microsaurs, principally through the morphology of the craniovertebral articulation.

This study aims to enlighten microfacies evolution and micropaleontological properties of the Tournaisian &amp / #8211 / Visean boundary in Aladag Unit (Central Taurides, Turkey). Two sections comprising dark shale and dark limestone alternations, including a fairly dolomitized part towards their top are measured. The microfacies analysis suggests a subtidal depositional environment. Foraminiferal assemblages were distinguished at Section AP and biozonation was documented. The biozonation separates the measured section into three zones, described as A, B and C. Zone A is scarce foraminifera fauna, and mainly contains Earlandia sp. Zone B is defined by appearance of a diversified foraminifera fauna and the first appearance of Lugtonia monilis (Malakhova, 1955) with Eoparastaffella sp. (morphotype 1). Zone C is defined according to the first appearance of Eoparastaffella simplex (Vdovenko, 1964) (morphotype 2) and foraminifers Laxaendothyra ex. gr. laxa. Tournaisian &amp / #8211 / Visean boundary is defined at the 60th sample, due to appearance of Eoparastaffella simplex (Vdovenko, 1964) (morphotype 2). Seven microfacies types in section AP, and six microfacies types in section PA are identified and, the intensely sampled part of the measured section AP is separated into 13 shallowing upward meter-scale cycles. These cycles, showing subtidal character are detected by both repetitions of microfacies and changes in abundance of foraminifers. A contrasting evaluation of the Tournaisian &amp / #8211 / Visean boundary of Taurides with Guangxi, South China and Dinant, Belgium is presented. The Chinese stratotype contains a diverse, more complete fauna of Tournaisian - Visean foraminifera, while the Belgium and Turkish sections are scarcer and most probably facies controlled.