Paul Comet
Texas A&M University, Texas A&M Transportation Institute, Department Member
... Scopus (10). R Castillo, L Devoe, G Falls, GB Holzman, AA Hamid and HE Fadel, Pleural effusion and pulmonary hypoplasia, Am J Obstet Gynecol 157 (1987), pp. 12521255. View Record in Scopus | Cited By in Scopus (31). WJ ...
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No evidence was found for isotopic fractionation at methyl carbon during methylation of fatty acids with BF 3 -methanol. It is therefore possible to evaluate intermolecular carbon isotopic variations in natural fatty acids by determining... more
No evidence was found for isotopic fractionation at methyl carbon during methylation of fatty acids with BF 3 -methanol. It is therefore possible to evaluate intermolecular carbon isotopic variations in natural fatty acids by determining the δ 13 C composition of the ...
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ABSTRACT The individual fatty acids of hydrocarbon seep mussels (seep mytilid II) and whitefish exhibit very light 13C values, from -50.0 to -57.9, and from -25.2 to -27.1, respectively. Unsaturated fatty acids have lighter 13C than... more
ABSTRACT The individual fatty acids of hydrocarbon seep mussels (seep mytilid II) and whitefish exhibit very light 13C values, from -50.0 to -57.9, and from -25.2 to -27.1, respectively. Unsaturated fatty acids have lighter 13C than saturated ones. The variations in 13C are up to 5.1 (mussel #1), 6.7 (mussel #2), and 2.7 (whitefish). A kinetic isotopic effect in the biosynthesis of fatty acids and intermolecular isotope fractionation during fatty acid desaturation and elongation is suggested to account for the observed distribution pattern. The systematic decrease of 13C in the order of mussel body, gill, and fatty acids, reflects the pathway of carbon flow as well as the biosynthetic locus in the mussels-bacteria system. Fatty acids of whitefish have significantly heavier 13C compared to those of mussels, reflecting distinctly different food source of the the animals.
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Summary An approach to palaeoenvironmental interpretation of sediments using lipid data, is developed. This approach initially attempts to summarize the major lipid components of plants, bacteria and invertebrate animals and to relate... more
Summary An approach to palaeoenvironmental interpretation of sediments using lipid data, is developed. This approach initially attempts to summarize the major lipid components of plants, bacteria and invertebrate animals and to relate these data to sedimentary lipid distributions. Most of the major lipid groups found in sediments are used in this study. The very large amount of lipid data generated, necessitated the development of a simple system for data processing. The method of data analysis used involved the construction of a simple taxonomic hierarchy based on ‘Ruzicka’s Rules’ i.e. the biosynthetic origins of the major lipid types. By bringing in the concept of taxonomic hierarchy based on the biosynthetic pathways, a palaeontological approach towards lipid geochemistry is being evolved. Secondly, DSDP lipid data (derived from the O.G.U., Bristol University) are collated and grouped using matrices of lipid data and histograms of the lipid groups, i.e. all compounds of a common structure are ‘summed’. These data are compared with the geological data and the results briefly discussed for each sediment. In conclusion, the diagenetically stable lipid patterns of three representative environments, i.e. marine planktonic, bacterially-dominated marine, and a lacustrine facies, are presented and discussed. From these data the rules by which environments are described are extended; the parameters so derived have good potential for source correlation.
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... It is noteworthy in reactions of B/A+B (described above) that precursor and product are implicitly related by simple "one-step" mechanisms. ... Hence, the 20 R/S C29 sterane ratio may not be the one-step [A] [B]... more
... It is noteworthy in reactions of B/A+B (described above) that precursor and product are implicitly related by simple "one-step" mechanisms. ... Hence, the 20 R/S C29 sterane ratio may not be the one-step [A] [B] simple ratio described by Mackenzie (1984). ...
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... 4. Selected palynomorphs from the Manning Formation (Jackson Group) outcrop in the Lake Somerville spillway. ... Several bisnorhopanes/enes occur in the four lignite samples including a bisnorhop-diene ('b'), a bisnorhopene... more
... 4. Selected palynomorphs from the Manning Formation (Jackson Group) outcrop in the Lake Somerville spillway. ... Several bisnorhopanes/enes occur in the four lignite samples including a bisnorhop-diene ('b'), a bisnorhopene ('f') and bisnorhopane ('h') (Figs. ...
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Summary An approach to palaeoenvironmental interpretation of sediments using lipid data, is developed. This approach initially attempts to summarize the major lipid components of plants, bacteria and invertebrate animals and to relate... more
Summary An approach to palaeoenvironmental interpretation of sediments using lipid data, is developed. This approach initially attempts to summarize the major lipid components of plants, bacteria and invertebrate animals and to relate these data to sedimentary lipid distributions. Most of the major lipid groups found in sediments are used in this study. The very large amount of lipid data generated, necessitated the development of a simple system for data processing. The method of data analysis used involved the construction of a simple taxonomic hierarchy based on ‘Ruzicka’s Rules’ i.e. the biosynthetic origins of the major lipid types. By bringing in the concept of taxonomic hierarchy based on the biosynthetic pathways, a palaeontological approach towards lipid geochemistry is being evolved. Secondly, DSDP lipid data (derived from the O.G.U., Bristol University) are collated and grouped using matrices of lipid data and histograms of the lipid groups, i.e. all compounds of a common structure are ‘summed’. These data are compared with the geological data and the results briefly discussed for each sediment. In conclusion, the diagenetically stable lipid patterns of three representative environments, i.e. marine planktonic, bacterially-dominated marine, and a lacustrine facies, are presented and discussed. From these data the rules by which environments are described are extended; the parameters so derived have good potential for source correlation.
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Logging data are measurements of physical properties of the formation surrounding a borehole, acquired in situ after completion of coring (wireline logging) or during drilling (Logging-While-Drilling, LWD). The range of data (resistivity,... more
Logging data are measurements of physical properties of the formation surrounding a borehole, acquired in situ after completion of coring (wireline logging) or during drilling (Logging-While-Drilling, LWD). The range of data (resistivity, gamma radiation, velocity, density, borehole images,…) in any hole depends on the scientific objectives and operational constraints.
Logging data are measurements of physical properties of the formation surrounding a borehole, acquired in situ after completion of coring (wireline logging) or during drilling (Logging-While-Drilling, LWD). The range of data (resistivity,... more
Logging data are measurements of physical properties of the formation surrounding a borehole, acquired in situ after completion of coring (wireline logging) or during drilling (Logging-While-Drilling, LWD). The range of data (resistivity, gamma radiation, velocity, density, borehole images,…) in any hole depends on the scientific objectives and operational constraints.
Logging data are measurements of physical properties of the formation surrounding a borehole, acquired in situ after completion of coring (wireline logging) or during drilling (Logging-While-Drilling, LWD). The range of data (resistivity,... more
Logging data are measurements of physical properties of the formation surrounding a borehole, acquired in situ after completion of coring (wireline logging) or during drilling (Logging-While-Drilling, LWD). The range of data (resistivity, gamma radiation, velocity, density, borehole images,…) in any hole depends on the scientific objectives and operational constraints.
The individual fatty acids of hydrocarbon seep mussels (seep mytilid II) and whitefish exhibit very light 13C values, from -50.0 to -57.9, and from -25.2 to -27.1, respectively. Unsaturated fatty acids have lighter 13C than saturated... more
The individual fatty acids of hydrocarbon seep mussels (seep mytilid II) and whitefish exhibit very light 13C values, from -50.0 to -57.9, and from -25.2 to -27.1, respectively. Unsaturated fatty acids have lighter 13C than saturated ones. The variations in 13C are up to 5.1 (mussel #1), 6.7 (mussel #2), and 2.7 (whitefish). A kinetic isotopic effect in the biosynthesis of fatty acids and intermolecular isotope fractionation during fatty acid desaturation and elongation is suggested to account for the observed distribution pattern. The systematic decrease of 13C in the order of mussel body, gill, and fatty acids, reflects the pathway of carbon flow as well as the biosynthetic locus in the mussels-bacteria system. Fatty acids of whitefish have significantly heavier 13C compared to those of mussels, reflecting distinctly different food source of the the animals.
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Geology and Geochemistry
A series of propositions for the development of sustainable, carbon neutral communities are given in which local economies use waste as their resource base. Applications to a lunar/Martian base, refugee camps & other autonomous systems... more
A series of propositions for the development of sustainable, carbon neutral communities are given in which local economies use waste as their resource base. Applications to a lunar/Martian base, refugee camps & other autonomous systems are briefly considered in the building of a circular economy. The problem of “material entropy” is considered, & a currency based on alternative energy is proposed as a way of “autotrophic” or “negentropic” handling the present “linear economy”. The various ideas all stem from biological models of sustainability. Though communism is not recommended (mandatory, bureaucratic “sharing” of resources), the present market economy may need reform if “circularity” is to be developed from the present linear, waste - producing system.
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Environmental Science, Geology, Astrobiology, Waste Management, Municipal Solid Waste, and 12 moreCarbon Footprint, Production economics, Sorghum, Biofuel, ELECTRICAL RESISTIVITY TOMOGRAPHY, GREEN HOUSE, Precipitation, HAZARD, Pulp and Paper Industry, Footprint, Hazard Analysis, and Lignocellulosic Biomass
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Natural ecosystems provide network models for human waste disposal where detritovores & otherdecomposers keep the habitat clean & provide much needed nutrients to photosynthetic organisms. In returnthe decomposer receives the energy &... more
Natural ecosystems provide network models for human waste disposal where detritovores & otherdecomposers keep the habitat clean & provide much needed nutrients to photosynthetic organisms. In returnthe decomposer receives the energy & nutrients sequestered in dung, cadavers or phytal debris. This is doneby accessing a range of biosynthetic pathways that can utilise biological waste as a primary feedstock. Thesepathways may involve oxidation or fermentation. Different decomposers have different specializations.Examples might be brown rot fungi eating wood cellulose & white rot fungi eating the lignins also from wood.Photosynthesis, respiration & decomposition can be observed in the model environment of a small glassecosphere, containing shrimps, algae & bacteria rich sediment, which when set by a window, can be (withsome difficulty) maintained to be indefinitely sustainable. In the ecosphere the Calvin (photosynthetic), Krebs(respiratory), & the fermentation cycles can be inferred to...
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Abstract Four hundred and eighty-one Gulf of Mexico oils and condensates can be subdivided into nine major families based on their sterane ( m / z 217, 218) and triterpane ( m / z 191, 177) biomarker mass chromatogram patterns. These... more
Abstract Four hundred and eighty-one Gulf of Mexico oils and condensates can be subdivided into nine major families based on their sterane ( m / z 217, 218) and triterpane ( m / z 191, 177) biomarker mass chromatogram patterns. These families are (1) carbonate-sourced oils reservoired in Jurassic-Cretaceous reservoirs onshore and Plio-Pleistocene reservoirs offshore, (2) Austin Chalk reservoired oils, (3) Tuscaloosa oils, (4) Wilcox reservoired oils (La), (5) South Texas Palaeogene reservoired oils, (6) Mississippi delta oils, (7) post-mature oils of uncertain affinities, (8) migration contaminated oils (showing attributes of a mixing of immature and post-mature sources), and (9) oils and condensates lacking biomarkers. Each oil family is concentrated in specific age-defined producing trends, ranging in age from Jurassic to Pleistocene. For Tertiary reservoirs, these producing trends shift geographically with time, in a manner analogous to the clockwise migrating Cenozoic depocenter model for the northern Gulf of Mexico. At least six ages of marine source rock deposition may be implicated in the genesis of these oils (1) The Kimmeridgian-Oxfordian (including Smackover and Norphlet formations), (2) The Aptian (including Pine Island, Bexar and Sunniland formations), (3) The Albian (Paluxy formation), (4) The Cenomanian-Turonian (including Eagle Ford and Tuscaloosa formations), (5) The Coniacian-Santonian (Eagle Ford and Austin Chalk), and (6) The Palaeocene (Wilcox, Midway, Sparta formations). The Jurassic and Cretaceous source rocks correspond to described oceanic anoxic events of probable global significance. This paper will concentrate on describing the biomarker patterns of the oils and postulated source rocks, but due to reasons of space, isotopic, elemental and other data will only be briefly discussed.