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Author

James A. Harrell

Other affiliations: University of Cincinnati
Bio: James A. Harrell is an academic researcher from University of Toledo. The author has contributed to research in topics: Sorting & Plane (geometry). The author has an hindex of 14, co-authored 46 publications receiving 546 citations. Previous affiliations of James A. Harrell include University of Cincinnati.
Topics: Sorting, Plane (geometry), Wadi, Papyrus, Radon

Papers
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Journal ArticleDOI
TL;DR: The first evidence for the use of an indigenous source of bitumen in ancient Egypt was provided by as mentioned in this paper, who used molecular biomarkers derived from gas chromatography/mass spectrometry.
Abstract: Bitumen used as a preservative in ancient Egyptian mummies was previously thought to come only from the Dead Sea in Palestine. Other, closer sources of bitumen were investigated at Abu Durba and Gebel Zeit on the shores of Egypt’s Gulf of Suez. Bitumen from these localities and from five mummies was analysed using molecular biomarkers derived from gas chromatography/mass spectrometry. It was found that four of the mummies contained Dead Sea bitumen, and the fifth and oldest (900 bc) had bitumen from Gebel Zeit, thus providing the first evidence for the use of an indigenous source of bitumen in ancient Egypt.

82 citations

Journal ArticleDOI
TL;DR: A papyrus map discovered around 1820 and now in the Egyptian Museum in Turin, Italy, illustrates the topography and geology of Wadi Hammamat in the mountains of the central Eastern Desert of Egypt as discussed by the authors.
Abstract: A papyrus map discovered around 1820 and now in the Egyptian Museum in Turin, Italy, illustrates the topography and geology of Wadi Hammamat in the mountains of the central Eastern Desert of Egypt. It accurately depicts the areal distribution of sedimentary and igneous/metamorphic rocks, which are shown as black and pink hills, respectively. The ancient map also shows the gold-working settlement at Bir Umm Fawakhir, the gold-bearing quartz veins on the adjacent mountain, the famous "bekhen-stone" quarry, the lithologically diverse wadi gravels, and various cultural features. Hieratic texts on the map comment on the occurrence of gold in the area and the quarrying of bekhen-stone (grayish-green chloritic sandstones and siltstones). This papyrus is the oldest surviving geological map in the world, and it predates by 29 centuries the next oldest known geological map. The map was drawn during the reign of Ramesses IV (1151-1145 B.C.) as an aid to or a record of one of this king's bekhen-stone quarrying expedi...

41 citations

Journal ArticleDOI
TL;DR: In this article, a time-series analysis of climatic periodicities which correspond to secular changes in the earth's orbital parameters was performed using the Periodic Regression with Cyclic Descent (PRDC) method.

41 citations


Cited by
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MonographDOI
16 Dec 2004
TL;DR: The second edition of The Biomarker Guide as mentioned in this paper provides a comprehensive account of the role that biomarker technology plays both in petroleum exploration and in understanding Earth history and processes.
Abstract: The second edition of The Biomarker Guide is a fully updated and expanded version of this essential reference. Now in two volumes, it provides a comprehensive account of the role that biomarker technology plays both in petroleum exploration and in understanding Earth history and processes. Biomarkers and Isotopes in the Environment and Human History details the origins of biomarkers and introduces basic chemical principles relevant to their study. It discusses analytical techniques, and applications of biomarkers to environmental and archaeological problems. The Biomarker Guide is an invaluable resource for geologists, petroleum geochemists, biogeochemists, environmental scientists and archaeologists.

2,163 citations

Book ChapterDOI
01 Jan 1985
TL;DR: In this paper, the authors compare sandstone compositions by grouping diverse grain types into a few operational categories having broad genetic significance and displaying compositional fields associated with different provenances on standard triangular diagrams.
Abstract: Detrital modes of sandstone suites primarily reflect the different tectonic settings of provenance terranes, although various other sedimentological factors also influence sandstone compositions. Comparisons of sandstone compositions are aided by grouping diverse grain types into a few operational categories having broad genetic significance. Compositional fields associated with different provenances can then be displayed on standard triangular diagrams.

1,431 citations

Journal ArticleDOI
TL;DR: In this paper, a detailed record of climate changes during the last 2.5 million years in central China has been provided, at least 44 major shifts from glacial to interglacial conditions occurred during this time in China.

787 citations

Journal ArticleDOI
TL;DR: Organic residue analysis utilizes analytical organic chemical techniques to identify the nature and origins of organic remains that cannot be characterized using traditional techniques of archaeological investigation (because they are either amorphous or invisible).
Abstract: Organic residue analysis utilizes analytical organic chemical techniques to identify the nature and origins of organic remains that cannot be characterized using traditional techniques of archaeological investigation (because they are either amorphous or invisible). The field is founded upon the principle that the biomolecular, or biochemical, components of organic materials associated with human activity survive in a wide variety of locations and deposits at archaeological sites. The archaeological information contained in organic residues is represented by the biomolecular components of the natural products that contribute to the formation of a given residue. By applying appropriate separation (chromatographic) and identification (mass spectrometric) techniques, the preserved, and altered, biomolecular components of such residues can be revealed. Once identified, the Archaeological Biomarker Concept can be applied, wherein the structure and even isotopic composition(s) of a given biomolecule or suite of biomolecules (the ‘chemical fingerprint’) can be related to the compositions of organisms exploited by humans in the past. As the organic residue field emerges from its pre-paradigmatic phase, and the organic residue revolution gathers pace, the way is open for challenging many long-held archaeological hypotheses and offering new perspectives on the study of human activity in the past.

468 citations

Journal ArticleDOI
TL;DR: In this article, the main classes of arenites are classified into four main groups: non-carbonate extrabasinal, carbonate extrabaasinal and carbonate intraboasinal.
Abstract: Misinterpretations of modes of arenites containing framework grains of both intrabasinal and extrabasinal origin lead to unreliable reconstructions of paleobasins and paleosource areas. A satisfactory scheme for the classification of such hybrid arenites is needed to provide an adequate framework for basra analysis. Criteria for the definition of the chief classes of arenites must distinguish between extrabasinal and intrabasinal detritus and minimize the dependence of arenite nomenclature on grain size. Four main groups of arenaceous grain types are recognized: 1) noncarbonate extrabasinal, 2) carbonate extrabasinal, 3) noncarbonate intrabasinal, and 4) carbonate intrabasinal. Their three dimensional configuration establishes a first-level classification o the main types of arenites. Two more groups of arenaceous modes, neovolcanic and carbonate particles of extra- or intrabasinal undetermined origin, are required for a practical scheme. The practicability of the suggested approach can be demonstrated in paleogeographic and paleotectonic reconstructions.

335 citations