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Paul C Hackley

Research Geologist

Geology, Energy & Minerals Science Center

Office Phone: 703-648-6458
Fax: 703-648-6419
ORCID: 0000-0002-5957-2551

John W Powell FB
12201 Sunrise Valley Drive
Reston , VA 20192-0002

Supervisor: Evan A Bargnesi
To test if reflectance increases to sedimentary organic matter (vitrinite) caused by broad ion beam (BIB) milling were related to molecular aromatization and condensation, we used Raman and Fourier transform infrared (FTIR) spectroscopies to evaluate potential compositional changes in the same vitrinite locations pre- and post-BIB milling. The same locations also were examined by atomic force microscopy (AFM) to determine topographic changes caused by BIB milling (as expressed by the areal root-mean-square roughness parameter Rq). Samples consisted of four medium volatile bituminous coals. We used a non-aggressive BIB milling approach with conditions of [(5 min, 4 keV, 15°incline, 360° rotation at 25 rpm and 100%...
Solid organic matter (OM) in sedimentary rocks produces petroleum and solid bitumen when it undergoes thermal maturation. The solid OM is a 'geomacromolecule', usually representing a mixture of various organisms with distinct biogenic origins, and can have high heterogeneity in composition. Programmed pyrolysis is a common conventional method to reveal bulk geochemical characteristics of the dominant OM while detailed organic petrography is required to reveal information about the biogenic origin of contributing macerals. Despite advantages of programmed pyrolysis, it cannot provide information about the heterogeneity of chemical compositions present in the individual OM types. Therefore, other analytical techniques...
The refractory nature of zircon to temperature and pressure allows even a single zircon grain to preserve a rich history of magmatic, metamorphic, and hydrothermal processes. Isotopic dating of micro-domains exposed in cross-sections of zircon grains allows us to interrogate this history. Unfortunately, our ability to select the zircon grains in a heavy mineral concentrate that records the most geochronologic information is limited by our inability to predict internal zonation from observations of whole zircon grains. Here we document the use of a petrographic microscope to observe and image the photoluminescence (PL) response of whole zircon grains excited under ultraviolet (UV) light, and the utility of this PL...
For nearly two and a half decades following World War II, production wastes from the world’s largest manufacturer of technical DDT were discharged into sewers of Los Angeles County. Following treatment, the wastes were released via a submarine outfall system to nearshore coastal waters where a portion accumulated in shallow sediments of the Palos Verdes Shelf (PVS). An investigation of the pore-water geochemistry of DDT-related compounds (DDX) was undertaken in an effort to understand factors controlling the rate of reductive dechlorination (RDC) of the major DDT degradate, 4,4’-DDE. Equilibrium matrix-solid phase microextraction (matrix-SPMEeq) combined with automated thermal desorption-gas chromatography/mass...
Recent production of light sweet oil from shallow (~2,000 ft) horizontal wells in the Upper Devonian Berea Sandstone of eastern Kentucky and historical oil production from conventional wells in the Berea of adjoining southern Ohio has prompted re-evaluation of Devonian petroleum systems in the central Appalachian Basin. Herein, we examined Upper Devonian Ohio Shale (lower Huron Member) and Middle Devonian Marcellus Shale organic-rich source rocks from eastern Ohio and nearby areas using organic petrography and geochemical analyses of solvent extracts. The data indicate the organic matter in the Ohio and Marcellus Shales was primarily derived from marine algae and its degradation products including bacterial biomass....
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