M. A. Sephton

Publication List Details

Period

1999 - 2007

Number

33

Co-Authors

Exploration of Ellsworth Subglacial Lake: a concept paper on the development, organisation and execution of an experiment to explore, measure and sample the environment of a West Antarctic subglacial lake (2007)

Siegert, M.J., Behar, A., Bentley, M., Blake, D., Christoffersen, P., Cockell, C., ...

Antarctic subglacial lakes have, over the past few years, been hypothesised to house unique forms of life and hold detailed sedimentary records of past climate change. Testing this hypothesis...

The labelling of meteoritic organic material using osmium tetroxide vapour impregnation (2007)

Pearson, V. K., Kearlsey, A. T., Sephton, M. A., Gilmour, I.

We present a method for labelling and locating organic material in extraterrestrial samples in order to determine its spatial arrangement in relation to inorganic components. We have taken a suite of...

The labelling of meteoritic organic material using osmium tetroxide vapour impregnation (2007)

Pearson, Victoria, Kearlsey, A. T., Sephton, M. A., Gilmour, Iain

We present a method for labelling and locating organic material in extraterrestrial samples in order to determine its spatial arrangement in relation to inorganic components. We have taken a suite of...

Carbon and nitrogen in carbonaceous chondrites: elemental abundances and stable isotopic compositions (2006)

Pearson, Victoria, Sephton, M.A., Franchi, Ian, Gibson, Jennifer, Gilmour, Iain

We have undertaken a comprehensive study of carbon and nitrogen elemental abundances and isotopic compositions of bulk carbonaceous chondrites. A strategy of multiple analyses has enabled the...

Free dicarboxylic and aromatic acids in the carbonaceous chondrites Murchison and Orgueil (2006)

Martins, Z., Watson, J.S., Sephton, M.A., Botta, O., Ehrenfreund, P., Gilmour, I.

We have analyzed an important fraction of the free carboxylic acids present in water extracts of the CM2 chondrite Murchison and the Cl I chondrite Orgueil using gas chromatography-mass spectrometry...

Macromolecular organic acids in the Murchison meteorite (2005)

Watson, J. S., Sephton, M. A., Gilmour, I.

This study has detected bound organic acids within the Murchison meteorite organic macromolecule. Benzoic acid was the most abundant compound; other abundant compounds include C1 and C2 benzoic...

The combustion characteristics and stable carbon isotopic compositions of irradiated organic matter: implications for terrestrial and extraterrestrial sample analysis (2005)

Court, R. W., Sephton, M. A., Parnell, J., Gilmour, I.

Exposure to ionizing radiation causes the mean combustion temperature of naturally occurring, solid, terrestrial organic matter, derived from the radiation-induced polymerization of methane, to...

The combustion characteristics and stable carbon isotopic compositions of irradiated organic matter: implications for terrestrial and extraterrestrial sample analysis (2005)

Court, R. W., Sephton, M. A., Parnell, J., Gilmour, I.

Exposure to ionizing radiation causes the mean combustion temperature of naturally occurring, solid, terrestrial organic matter, derived from the radiation-induced polymerization of methane, to...

Carbon and nitrogen isotope ratios in meteoritic organic matter: indicators of alteration processes on the parent asteroid (2004)

Sephton, M. A., Verchovsky, Sasha, Wright, Ian

Macromolecular organic materials in chondrites display significant variations in carbon and nitrogen stable isotopes. In recent years, these variations have been interpreted as a record of aqueous...

The preservation state of organic matter in meteorites from Antarctica (2004)

Sephton, M.A., Bland, P.A., Pillinger, C.T., Gilmour, I.

The recovery of large numbers of meteorites from Antarctica has dramatically increased the amount of extraterrestrial material available for laboratory studies of solar system origin and evolution....

Hydropyrolysis of insoluble carbonaceous matter in the Murchison meteorite: new insights into its macromolecular structure (2004)

Sephton, M.A., Love, G.D., Watson, J.S., Verchovsky, A.B., Wright, I.P., Snape, C.E., ...

The major organic component of carbonaceous chondrites is a solvent-insoluble, high molecular weight macromolecular material that constitutes at least 70% of the total organic content in these...

Investigating the variations in carbon and nitrogen isotopes in carbonaceous chondrites (2003)

Sephton, M.A., Verchovsky, A.B., Bland, P.A., Gilmour, I., Grady, M.M., Wright, I.P.

The carbonaceous chondrites contain significant amounts of carbon- and nitrogen-bearing components, the most abundant of which is organic matter. Stepped combustion data of whole rock and HF/HCl...

Hydropyrolysis of high molecular weight organic matter in Murchison (2003)

Sephton, M. A., Love, G. D., Watson, J. S., Verchovsky, A. B., Wright, I. P., Snape, C. E., ...

Hydropyrolysis of the Murchison macromolecular material releases polyaromatic compounds including phenanthrene, carbazole, fluoranthene, pyrene, chrysene, perylene, benzoperylene and coronene units...

Organic Geochemistry of a Hydrocarbon-rich Calcarenite from the Chicxulub Scientific Drilling Program (2003)

Gilmour, Iain, Sephton, M. A., Morgan, J. V.

The organic geochemistry of hydrocarbon-rich core material recovered by the CSDP is examined to establish whether hydrocarbons are associated with the migration and emplacement of organic matter by...

High molecular weight organic matter in martian meteorites (2002)

Sephton, M.A., Wright, I.P., Gilmour, I., De Leeuw, J.W., Grady, M.M., Pillinger, C.T.

We have performed an investigation to detect high molecular weight organic matter in martian meteorites. Solvent-extracted samples of two Antarctic finds (ALH 84001, sub-sample 106 and EET A79001,...

Separation of planetary noble gas carrier from bulk carbon in enstatite chondrites during stepped combustion (2002)

Verchovsky, A.B., Sephton, M.A., Wright, I.P., Pillinger, C.T.

The exact location of planetary noble gases in meteorites remains unknown but it is inferred to be closely associated with, if not precisely some portion of, the macromolecular organic material in...

Production of high molecular weight organic compounds on the surfaces of amorphous iron silicate catalysts: Implications for organic synthesis in the solar nebula (2002)

Gilmour, I., Hill, H. G. M., Pearson, V.K., Sephton, M.A, Nuth, J. A.

The high molecular weight organic products of Fischer-Tropsch/Haber-Bosch syntheses on the surfaces of Fe-silicate catalysts have been studied by GCMS.

Organic-inorganic spatial relationships in carbonaceous chondrites (2002)

Pearson, V. J., Kearsley, A. T., Sephton, M. A., Gilmour, I.

The use of a novel technique to determine the spatial relationships of organic and aqueously produced inorganic phases in carbonaceous chondrites, in order to support proposals of a genetic link...

Organic indicators of alteration in the CR chondrites (2002)

Pearson, V. K., Sephton, M. A., Gilmour, I.

A study of the organic components in the CR chondrite macromolecule in order to assess the role of pre-terrestrial alteration on the organic inventory.

Compound-specific isotope analysis of the organic constituents in carbonaceous chondrites (2001)

Sephton, M. A., Gilmour, I.

The carbonaceous chondrite meteorites contain evidence of the formation of the solar system, part of which is present within organic matter. In recent years, compound-specific isotope analysis (CSIA)...

Normal alkanes in meteorites: molecular δ13C values indicate an origin by terrestrial contamination (2001)

Sephton, M.A., Pillinger, C.T., Gilmour, I.

In the time period since 1961, n-alkanes (straight-chain hydrocarbons) have been detected in varying amounts in many meteorites. Proposed origins for these compounds have included extraterrestrial...

Supercritical fluid extraction of the non-polar organic compounds in meteorites (2001)

Sephton, M.A., Pillinger, C.T., Gilmour, I.

The carbonaceous chondrite meteorites contain a variety of extraterrestrial organic molecules. These organic components provide a valuable insight into the formation and evolution of the solar...

Pyrolysis–gas chromatography–isotope ratio mass spectrometry of macromolecular material in meteorites (2001)

Sephton, M. A., Gilmour, Iain

A number of extraterrestrial objects, such as meteorites and interplanetary dust particles, are known to contain organic matter in the form of complex macromolecular materials. These organic networks...

The association between organic matter and clay minerals in carbonaceous chondrites (2001)

Pearson, V. K., Sephton, M. A., Bland, P. A., Franchi, I. A., Gilmour, I.

There is an established relationship between organic matter content and aqueous alteration processes [1,2]. However, the relationship between meteoritic organic matter and individual aqueously...

Analysis of Tagish Lake macromolecular organic material (2001)

Gilmour, I., Pearson, V. K., Sephton, M. A.

Macromolecular material is, by far, the major organic component of meteorites. Flash pyrolysis GCMS has been used to investigate this organic component in Tagish Lake. It is more condensed, less...

Dual isotopic composition of methane in Murchison meteorite (2001)

Butterworth, A. L., Sephton, M. A., Gilmour, I.

Dual isotopic composition (H and C) of methane extracted from a small sample of Murchison meteorite reveals a deuterium enrichment for this molecule, indicating the presence of interstellar hydrogen.

Hydrogen isotopic composition of the Tagish Lake meteorite: comparison with other carbonaceous chondrites (2001)

Pearson, V. K., Sephton, M. A., Gilmour, I., Franchi, I. A.

A study into the hydrogen isotopic characteristics of whole rock samples of carbonaceous chondrites and their comparison with a whole rock sample of the Tagish Lake meteorite.

Cyclic diaryl ethers in a Late Permian sediment (1999)

Sephton, M.A., Looy, C.V., Veefkind, R.J., Visscher, H., Brinkhuis, H., Leeuw, J.W. De

Abundant cyclic diaryl ethers, such as dibenzofuran and its alkyl derivatives are found in solvent extracts and kerogen pyrolysates of a Late Permian organic-rich marl from northern Italy. These...