Shale Samples (shale + sample)

Distribution by Scientific Domains


Selected Abstracts


Investigation of mineral composition of oil shale

ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 5 2009
Dong-Mei Wang
Abstract The aim of this paper is to identify the mineral composition of oil shale from different locations and relate it to their interval of occurrence. Thermogravimetric analysis (TGA), diffuse reflectance infrared Fourier transforms spectroscopy (DRIFTS) and X-ray diffraction (XRD) methods were used for this invetigation. Hydrogen peroxide was used as the oxidant to eliminate the influence of organic matter in TGA. DRIFTS results indicated that most of the kerogen is in aliphatic hydrocarbon form and the peak of hydrocarbon nearly disappeared after oxidation. XRD results indicated that quartz, muscovite, kaolinite and calcite are the dominant minerals. Longkou and Changchun oil shale samples contain high percentage of calcite (12.9 and 11.7% CO2 respectively) while Fushun and Huadian oil shale samples contain less than 6% CO2. Especially, in Fushun oil shale sample, the content is below 3%. Kaolinite is found in Fushun oil shale sample, while muscovite is only found in Huadian oil shale sample. Integration of the XRD, DRIFTS and TGA results of the oil shale samples from different locations has provided a better way of mineral composition identification. Copyright 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source]


Palynological evidence for Pennsylvanian (Late Carboniferous) vegetation change in the Sydney Coalfield, eastern Canada

GEOLOGICAL JOURNAL, Issue 4 2010
Tatyana K. Dimitrova
Abstract The palynology of clastic samples from seven stratigraphical levels in the late Moscovian Sydney Mines Formation, exposed along the shore at Bras d'Or, Nova Scotia, has been investigated. Most of the samples were from roof shales of major coals; the one sample that was not yielded a much higher proportion of pollen derived from extra-basinal vegetation. The four stratigraphically lower roof shale samples yielded essentially similar palynological spectra, with 39,,4% lycophytes, 9,,4% sphenophylls, 23,,4% tree-ferns, 12,,4% other ferns and 5,,3% cordaites. The palynology of the upper part of the investigated succession suggests a shift in vegetation towards one favouring more marattialean tree-ferns, cordaites and conifers, and fewer lycophytes. This correlates with changes in drainage patterns as the alluvial plain migrated seawards and thus changed water tables. No evidence was found to suggest significant climate change at this time. Copyright 2009 John Wiley & Sons, Ltd. [source]


A RE-APPRAISAL OF THE APPLICATION OF ROCK-EVAL PYROLYSIS TO SOURCE ROCK STUDIES IN THE NIGER DELTA

JOURNAL OF PETROLEUM GEOLOGY, Issue 1 2005
A. Akinlua
Thirty four shale samples from the Tertiary Agbada Formation were analysed for TOC and Rock-Eval pyrolysis parameters in order to evaluate the effect of oil-based mud contamination on source-rock characterization. The samples were obtained from five wells in the offshore Niger Delta over a depth range of 5,460ft to 11,580ft. The results indicated that the raw (unextracted) samples were dominated by Type III kerogen. However, after extraction, both Types II/III and III kerogen were identified, consistent with previous studies. These results demonstrate that it is essential that shale samples should be extracted prior to TOC and Rock-Eval pyrolysis for accurate source-rock evaluation. [source]


Chemical, Isotopic, and Fluid Inclusion Evidence for the Hydrothermal Alteration of the Footwall Rocks of the BIF-Hosted Iron Ore Deposits in the Hamersley District, Western Australia

RESOURCE GEOLOGY, Issue 2 2003
Makoto Haruna
Abstract. The petrography, chemical, fluid inclusion and isotope analyses (O, Rb-Sr) were conducted for the shale samples of the Mount McRae Shale collected from the Tom Price, Newman, and Paraburdoo mines in the Hamersley Basin, Western Australia. The Mount McRae Shale at these mines occurs as a footwall unit of the secondary, hematite-rich iron ores derived from the Brockman Iron Formation, one of the largest banded iron formations (BIFs) in the world. Unusually low contents of Na, Ca, and Sr in the shales suggest that these elements were leached away from the shale after deposition. The ,18O (SMOW) values fall in the range of + 15.0 to +17.9 per mil and show the positive correlation with calculated quartz/sericite ratios of the shale samples. This suggests that the oxygen isotopic compositions of shale samples were homogenized and equilibrated by postdepositional event. The pyrite nodules hosted by shales are often rimmed by thin layers of silica of varying crystallinity. Fluid inclusions in quartz crystals rimming a pyrite nodule show homogenization temperatures ranging from 100 to 240d,C for 47 inclusions and salinities ranging from 0.4 to 12.3 wt% NaCl equivalent for 18 inclusions. These fluid inclusion data give direct evidence for the hydrothermal activity and are comparable to those of the vein quartz collected from the BIF-derived secondary iron ores (Taylor et al, 2001). The Rb-Sr age for the Mount McRae Shale is 1,952 289 Ma and at least 200 million years younger than the depositional age of the Brockman Iron Formation of , 2.5 Ga in age. All the data obtained in this study are consistent with the suggestion that high temperature hydrothermal fluids were responsible for both the secondary iron ore formation and the alteration of the Mount McRae Shale. [source]


Investigation of mineral composition of oil shale

ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 5 2009
Dong-Mei Wang
Abstract The aim of this paper is to identify the mineral composition of oil shale from different locations and relate it to their interval of occurrence. Thermogravimetric analysis (TGA), diffuse reflectance infrared Fourier transforms spectroscopy (DRIFTS) and X-ray diffraction (XRD) methods were used for this invetigation. Hydrogen peroxide was used as the oxidant to eliminate the influence of organic matter in TGA. DRIFTS results indicated that most of the kerogen is in aliphatic hydrocarbon form and the peak of hydrocarbon nearly disappeared after oxidation. XRD results indicated that quartz, muscovite, kaolinite and calcite are the dominant minerals. Longkou and Changchun oil shale samples contain high percentage of calcite (12.9 and 11.7% CO2 respectively) while Fushun and Huadian oil shale samples contain less than 6% CO2. Especially, in Fushun oil shale sample, the content is below 3%. Kaolinite is found in Fushun oil shale sample, while muscovite is only found in Huadian oil shale sample. Integration of the XRD, DRIFTS and TGA results of the oil shale samples from different locations has provided a better way of mineral composition identification. Copyright 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source]


HYDROCARBON POTENTIAL OF THE LATE CRETACEOUS GONGILA AND FIKA FORMATIONS, BORNU (CHAD) BASIN, NE NIGERIA

JOURNAL OF PETROLEUM GEOLOGY, Issue 4 2010
B. Alalade
The hydrocarbon potential of possible shale source rocks from the Late Cretaceous Gongila and Fika Formations of the Chad Basin of NE Nigeria is evaluated using an integration of organic geochemistry and palynofacies observations. Total organic carbon (TOC) values for about 170 cutting samples range between 0.5% and 1.5% and Rock-Eval hydrogen indices (HI) are below 100 mgHC/gTOC, suggesting that the shales are organically lean and contain Type III/IV kerogen. Amorphous organic matter (AOM) dominates the kerogen assemblage (typically >80%) although its fluorescence does not show a significant correlation with measured HI. Atomic H/C ratios of a subset of the samples indicate higher quality oil- to gas-prone organic matter (Type II-III kerogens) and exhibit a significant correlation with the fluorescence of AOM (r2= 0.86). Rock-Eval Tmax calibrated against AOM fluorescence, biomarker and aromatic hydrocarbon maturity data suggests a transition from immature (<435C) to mature (>435C) in the Fika Formation and mature to post-mature (>470C) in the Gongila Formation. The low TOC values in most of the shales samples limit their overall source rock potential. The immature to early mature upper part of the Fika Formation, in which about 10% of the samples have TOC values greater than 2.0%, has the best oil generating potential. Oil would have been generated if such intervals had become thermally mature. On the basis of the samples studied here, the basin has potential for mostly gaseous rather than liquid hydrocarbons. [source]