The level of organic maturation, thermal history and petroleum source potential of Phanerozoic strata in northern Yukon and northwestern District of Mackenzie have been investigated by measurement of vitrinite (% Rorand) and graptolite (% Romax) reflectance, conodont alteration index (CAI) and Rock-Eval pyrolysis. The strata in general have lower maturity levels in southern Mackenzie Delta, Peel Plateau and Eagle Plain than in the Richardson and Ogilvie Mountains. The level of maturation varies from graptolite reflectance values of 4.0% to 6.5% Romax and CAI values of 3.5 to 5 in Upper Cambrian to Lower Devonian strata whereas vitrinite reflectance ranging from 0.2% to 3.75% Rorand occur in Middle Devonian to Upper Cretaceous strata. Time-averaged numerical modelling of measured maturation gradients (0.10 to 0.32 log Rorand/km) suggest paleogeothermal gradients on the order of 20 to 45°C/km in southern Mackenzie Delta and Peel Plateau, from 10 to 20°C/km in central Eagle Plain and from 20 to 45°C/km adjacent the Richardson and Ogilvie Mountains. The higher maturity levels in mountainous areas reflect higher maturation gradients and, in the Richardson Mountains, deeper burial due to rapid subsidence caused by the foundering of grabens within the Richardson Fault Array. Anomalously high maturation values (0.92% to 1.60% Rorand) measured in Lower Cretaceous strata on the Campbell Uplift are interpreted to reflect high paleoheat flow associated with basement uplift. Average TOC contents are generally low to moderate (0.1 to 2.0%) but organic-rich intervals occur throughout the studied succession. TOC values up to 14.5% are present in the Upper Cretaceous Eagle Plain Group, values up to 9.5% occur in the Middle Devonian Canol Formation and Upper Cambrian to Lower Devonian Road River Group and values up to 5.0% are present in the Lower Cretaceous map unit Kwr and Mount Goodenough Formation, the Lower Cretaceous and Jurassic Husky Formation, the Jurassic Porcupine River Formation and the Upper Carboniferous Blackie and Hart River Formations and the Ford Lake Shale. The organic matter (OM) is dominantly type III except for minor amounts of type I and II in Lower Paleozoic strata and a mixture of type II and III in parts of Middle Devonian, Carboniferous, Jurassic and Lower Cretaceous strata. The quality of organic matter varies significantly (QOM; 0.01 to 6.1 mg HC/g Corg) as a result of variation in organic maturity, the type of OM and, in some cases, migration. Average QOM values are generally low to moderate (0.01 to 1.5 mg HC/g Corg) and, along with low to moderate Hydrogen Index values (<300 mg HC/g Corg), suggest poor to moderate petroleum source potential. Relatively few examples of potential oil prone source rocks occur, but these include parts of the Road River Group, the Hare Indian, Canol, Hart River, Blackie, Mount Goodenough and Arctic Red River Formations, the Ford Lake Shale, unnamed Carboniferous unit and map unit Kwr. Gas prone source rocks comprise parts of the Blackie, Porcupine River, Husky, Mount Goodenough and Arctic Red River Formations and the Bug Creek and Eagle Plain Groups and map unit Kwr. With respect to petroleum generation, Upper Cretaceous strata are generally immature. Lower Cretaceous to Permian strata are immature to mature, Carboniferous strata are immature to overmature, and Devonian and older rocks are mature to overmature. The timing of hydrocarbon generation from source rocks in the study area varied substantially both laterally and stratigraphically as a result of variations in the timing and magnitude of the maximum depths of burial. The variation in source rock quality appears to closely reflect the interpreted depositional environment of some of the strata which facilitates the interpretation of regional extent of. potential hydrocarbon source rocks. A correlation of graptolite and vitrinite reflectance, calibrated by conodonts, shows that a graptolite reflectance range of 5% to 6.5% Romax (CAI = 5) corresponds to a vitrinite reflectance of 4.0% Romax. Graptolite organic remains appear to behave similar to bitumen with increasing depth of burial; at higher levels of thermal maturity, graptolite reflectance increases more rapidly than vitrinite reflectance. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

No description available.

Maps bound separately.

<p>The Short Time Fourier transform and the S-transform are among the most used methods of spectral decomposition to localize spectra in time and frequency. The S-transform utilizes a frequency-dependent Gaussian analysis window that is normalized for energy conservation purposes. The STFT, on the other hand, has a selected fixed time window that does not depend on frequency. In previous literature, it has been demonstrated that the S-transform distorts the Fourier spectra, shifting frequency peaks, and could result in misleading frequency attributes. Therefore, one way of making the S-transform more appropriate for quantitative seismic signal analysis is to ignore the conservation of energy over time requirement. This suggests a hybrid approach between the Short Time Fourier transform and the S-transform for seismic interpretation purposes. In this work, we introduce the Multi-Scale Boxcar transform that has temporal resolution comparable to the S-transform while giving correct Fourier peak frequencies. The Multi-Scale Boxcar transform includes a special analysis window that focusses the analysis on the highest amplitude portion of the Gaussian window, giving a more accurate time-frequency representation of the spectra in comparison with the S-transform. Post-stack seismic data with a strong well logs control was used to demonstrate the differences of the Multi-Scale Boxcar transform and the S-transform. The analysis area in this work is the Pennsylvanian and Lower Permian Horseshoe Atoll Carbonate play in the Midland Basin, a sub-basin in the larger Permian Basin. The Multi-Scale Boxcar transform spectral decomposition method improved the seismic interpretation of the study area, showing better temporal resolution for resolving the layered reservoirs? heterogeneity. The time and depth scale values on the figures are shifted according to the sponsor request, but the relative scale is correct.

Stratigraphy and source rock analyses of the Heath Formation in Fergus, Garfield, Golden Valley, Musselshell, Petroleum, and Rosebud counties, central Montana

<p> The Spraberry Formation is a Leonardian age submarine fan deposit restricted to the Midland Basin. The formation consists of very fine-grained sandstone, medium to coarse grain size siltstones, organic shales and carbonate mudstones. These rocks show variability in sedimentary structures and bedding types varied from thinly laminated to convolute laminations. Bioturbations were present in some samples and soft sediment deformation, such as water escape features, sediment loading and flame structures. </p><p> The Spraberry Formation is a naturally fractured reservoir with low porosity and low matrix permeability. Porosity measured varied from 2% in rocks with poor reservoir quality such as the argillaceous siltstone and mudstone while good reservoir rocks had an average porosity of 9%. Seven lithofacies were identified based on sedimentary structures, grain size and rock fabrics. Petrographic analysis showed four porosity types: (1) intragraular porosity; (2) dissolution porosity; (3) fracture porosity and (4) intergranular porosity. Fractured porosity was only observed in the argillaceous siltstone lithofacies. </p><p> The prominent diagenetic influences on the Spraberry Formation are: quartz cementation, quartz overgrowth, illtization of smectite, feldspar dissolution, clay precipitation, carbonate cementation, formation of framboidal pyrite and fracture formation. These diagenetic features were observed using scanning electron microscope (SEM) and in thin sections. Generally, petrophysical properties, such as porosity and permeability, vary gradually from reservoir rocks to non-reservoir rock. Observed trends where: 1) increasing organic and argillaceous content with decreasing porosity and 2) increasing carbonate sediments and calcite cements with decreasing porosity. Mineralogical analysis from FTIR showed an abundance of quartz and calcite, while illite is the prominent clay mineral observed in all samples.</p>

<p> Two industry acquired diatomite cores (Sisquoc Formation) from the Orcutt (Newlove 76-RD1) and Casmalia Hills (Stokes A-30804) oil fields were analyzed by core descriptions, laboratory analysis (XRD and SEM), and gamma ray logs. Based on these data, five distinct lithofacies, nine sedimentary features and compositional trends of both cores were established. Newlove 76-RD1 and Stokes A-30804 record an upward-shallowing succession at different depositional positions on the Pliocene paleo-slope of the Santa Maria basin. Stokes A-30804 reflects slope deposition on a lower flank of a paleo-bathymetric high receiving higher detrital influx from inter-ridge troughs. Slope deposition of Newlove 76-RD1 was closer to a paleo-bathymetric high where purer diatomaceous sediments accumulated. Within Stokes A-30804, purer opal-A dominant lithofacies contain the highest oil saturations. The diagenesis and precipitation of opal-CT and abundance of phyllosilicate significantly hinders oil saturation within lithofacies.</p>

Tertiary sediments taken from ten exploration wells and seven outcrop sections in the Bengal Basin together with thirteen oil and condensates and one oil seep and three oil soaked sandstones have been analysed using a variety of organic geochemical techniques. Detailed investigations of the distribution of biological marker compounds indicates that these soils (Surma Basin) are paraffinic waxy oils with a varying amount of C₂₁₊ n-alkanes typical of generation from source rocks rich in land plant waxes. The common occurrences of 24-norlupane and oleanane limits the age of the source rocks to Cretaceous or younger and most likely Tertiary. The selective occurrence of bicadinanes in the Surma Basin samples grouped the oils and condensates into two families suggesting the existence of more than one source rock. All the maturity parameters concur that the condensate samples from the Bengal foredeep region are of lower maturity and had been generated at the early stage of oil generation whilst the Surma Basin oils had been generated at around peak maturity of the source rock. The Hararganj oil seep and Sitakund oil-sands are severely biodegraded. The abundances of bicadinanes in Surma Basin oils indicate that they are not restricted to a few South East Asian (Indonesia, Sabah, Brunei) basins only. The occurrence of 24-norlupane has not yet been reported in crude oils and their presence in the Surma Basin oil and condensate samples suggests that they may also occur in Tertiary oils rich in angiosperm markers from other basins. Source characterisation of the various sample suites indicates the existence of at least three organic facies. The Upper Jenam samples with moderate to high organic richness contain abundant plant derived amorphous organic matter sufficient to qualify as a oil regnerating source rock. Maturity measurements of the Upper Jenam formation generally concur that the exposed sequences of this formation are insufficiently mature to have generated and expelled significant quantities of petroleum although the same formation in well sections is around the threshold of oil generation. Despite their immaturity, the source specific triterpane distributions in the Upper Jenam sediments indicates that they correlate closely with the Surma Basin oils. In terms of triterpane distribution the Bhuban sediments show a correlation with condensate samples. Despite their lean organic content, the huge volume of these sediments suggests that the Bhuban formation might have generated minor amounts of early mature condensate.

<p> Though the Cotton Valley Group is productive in Mississippi, Louisiana, and Texas, little is known about production potential of the Bossier Formation (Lower Cotton Valley Shale) in southwest Mississippi. The Bossier Formation in Jefferson County, Mississippi is an organic-poor, carbonate-rich mudrock with siliciclastic intervals. Examination of cuttings by petrographic and scanning electron microscopy revealed fractures that have been filled by calcite and pore-filling pyrite. Porosity exists within and around pyrite framboids, in unfilled fractures, and within peloid grains. Organic matter is rare in Lower Cotton Valley samples suggesting it is not self-sourcing. Total Organic Carbon (TOC) values are low (0.86-1.1% TOC) compared to the productive Haynesville Shale Formation (2.8% TOC). Porosity of the Lower Cotton Valley Shale is low (2.5-4.2%) compared to productive Haynesville Shale Formations (8-12%). With current technology and gas prices, the Lower Cotton Valley Shale in Jefferson County, Mississippi does not have production potential.</p>

<p> The Middle Devonian Marcellus Shale is a natural gas producing formation that was deposited in the Appalachian foreland basin in what is now eastern North America. An unconformity truncates the Marcellus in southern West Virginia and progressively younger units onlap progressively older units. The zero isopach line that marks the edge of the Marcellus is mapped to reveal the southeastern boundary. A well production analysis is conducted to locate the region of maximum natural gas production. Four lithologic completions intervals in three different well fields are compared. This study shows that the most economically viable drilling is from the Marcellus Shale completion intervals that are less than 30 feet in Chapmanville gas field in western Logan County, West Virginia. Outside of the zero isopach are areas comprised of onlapping featheredges of younger formations that comprise a black shale unit mistakenly identified as &ldquo;Marcellus Shale&rdquo;. These areas produce significantly less gas than the &ldquo;true&rdquo; Marcellus Shale.</p>