Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Physical Sciences and Mathematics
The Quartzite Problem Revisited, Jeffrey L. Howard
The Quartzite Problem Revisited, Jeffrey L. Howard
Environmental Science and Geology Faculty Research Publications
A review of past terminology and previous petrological studies suggests that quartzite should be classified descriptively as both a sedimentary and a metamorphic rock. Quartzite is identified in the field as a quartz‐rich rock (exclusive of chert and vein quartz) that is exceptionally hard and, when broken by a rock hammer, fractures irregularly through both grains and cement (where present) to form an irregular or conchoidal fracture surface. Quartzite is differentiated from quartzose sandstone (arenite), which is softer and fractures around individual grains, and from chert and vein quartz by a bright vitreous luster. Quartzite is classified further on the …
Interaction Of Sea Ice Sediments And Surface Sea Water In The Arctic Ocean: Evidence From Excess 210Pb, M. Baskaran
Interaction Of Sea Ice Sediments And Surface Sea Water In The Arctic Ocean: Evidence From Excess 210Pb, M. Baskaran
Environmental Science and Geology Faculty Research Publications
We measured the activities of 210Pb, 226Ra, 238U and 137Cs in a suite of ice-rafted sediments (IRS) from the Arctic Ocean in an attempt to assess the interaction of sea ice sediments and surface water. The concentrations of these nuclides were compared to those of the benthic sediments in the coastal and shelf regions of the Arctic Ocean, which are believed to be the major source region for the IRS. The concentration factors (CF = activity of a nuclide in IRS/average activity in benthic sediments) are ∼1 and 4-92 for 137Cs and 210Pb, respectively. …
Comparison Of Two-Dimensional And Three-Dimensional Simulations Of Dense Nonaqueous Phase Liquids (Dnapls): Migration And Entrapment Of A Nonuniform Permeability Field, John A. Christ, Lawrence D. Lemke, Linda M. Abriola
Comparison Of Two-Dimensional And Three-Dimensional Simulations Of Dense Nonaqueous Phase Liquids (Dnapls): Migration And Entrapment Of A Nonuniform Permeability Field, John A. Christ, Lawrence D. Lemke, Linda M. Abriola
Environmental Science and Geology Faculty Research Publications
The influence of reduced dimensionality (two-dimensional (2-D) versus 3-D) on predictions of dense nonaqueous phase liquid (DNAPL) infiltration and entrapment in statistically homogeneous, nonuniform permeability fields was investigated using the University of Texas Chemical Compositional Simulator (UTCHEM), a 3-D numerical multiphase simulator. Hysteretic capillary pressure–saturation and relative permeability relationships implemented in UTCHEM were benchmarked against those of another lab-tested simulator, the Michigan-Vertical and Lateral Organic Redistribution (M-VALOR). Simulation of a tetrachloroethene spill in 16 field-scale aquifer realizations generated DNAPL saturation distributions with approximately equivalent distribution metrics in two and three dimensions, with 2-D simulations generally resulting in slightly higher maximum …