The thermal maturity of shale is often measured by vitrinite reflectance (VRo). VRo measurements for the Devonian-Mississippian black shale source rocks evaluated herein predicted thermal immaturity in areas where associated reservoir rocks are oil-producing. This limitation of the VRo method led to the current evaluation of Raman spectroscopy as a suitable alternative for developing correlations between thermal maturity and Raman spectra. In this study, Raman spectra of Devonian-Mississippian black shale source rocks were regressed against measured VRo or sample-depth. Attempts were made to develop quantitative correlations of thermal maturity. Using sample-depth as a proxy for thermal maturity is not without limitations as thermal maturity as a function of depth depends on thermal gradient, which can vary through time, subsidence rate, uplift, lack of uplift, and faulting. Correlations between Raman data and vitrinite reflectance or sample-depth were quantified by peak-fitting the spectra. Various peak-fitting procedures were evaluated to determine the effects of the number of peaks and maximum peak widths on correlations between spectral metrics and thermal maturity. Correlations between D-frequency, G-band full width at half maximum (FWHM), and band separation between the G-and D-peaks and thermal maturity provided some degree of linearity throughout most peak-fitting assessments; however, these correlations and those calculated from the G-frequency, D/G FWHM ratio, and D/G peak area ratio also revealed a strong dependence on peak-fitting processes. This dependency on spectral analysis techniques raises questions about the validity of peak-fitting, particularly given the amount of subjective analyst involvement necessary to reconstruct spectra. This research shows how user interpretation and extrapolation affected the comparability of different samples, the accuracy of generated trends, and therefore, the potential of the Raman spectral method to become an industry benchmark as a thermal maturity probe. A Raman method devoid of extensive operator interaction and data manipulation is quintessential for creating a standard method.

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Currently, insufficient geological models exist to explain the variability and distribution of TOC in the Marcellus Shale, within the Hamilton Group. TOC is one of the several limiting factors for natural gas production within the Marcellus Shale basin. One possible explanation for the low TOC regions is that detrital dilution was variable across the basin, with different sediment sources contributing detritus to low TOC areas, compared to surrounding regions with higher TOC. This hypothesis is tested by analyzing the source composition of inorganic detritus, using elemental and mineralogical proxies, with two cores in the Hamilton Group. The Armstrong #1 core is located in Taylor County, West Virginia and the Coldstream Affiliates 1MH (CSA) core is located in Clearfield County, Pennsylvania. Both these wells are located outside of the higher productivity regions with a nearby horizontal Armstrong well totaling 0.45 BCF/1000ft lateral and a nearby horizontal CSA well totaling 0.41 BCF/1000ft lateral. Variation in production may also result from over maturation of the kerogen-hosted pores. To evaluate the influence of thermal history, the thermal maturity of the Marcellus Shale in the lower productivity Armstrong #1 and CSA wells and the higher productivity MSEEL well was assessed using Raman spectroscopy. Major element, trace element, and REE geochemistry indicate the sediment source area was composed of intermediate and felsic granitic and recycled sedimentary lithologies. Samarium-neodymium isotopic analysis reveals a range of DM ages and εNd values. The Armstrong #1 well DM / εNd ranged from 1.64 to 1.91 Ga /-11.93 to-9.56 and the CSA from 1.62 to 1.88 Ga /-12.07 to-11.12. The εNd values became more negative upsection, however the DM did not display a consistent trend relative to depth. Provenance analysis indicates the most likely source of clastic sediment was the Acadian Fold-Thrust Belt to the east with minor inputs from Superior Craton and southern Canadian Grenville Province. Ultimately, results conclude that elevated TOC was associated with only older DM ages and recycled sedimentary signatures. iii TABLE OF CONTENTS