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Pennsylvanian Deltaic Sedimentation In Grand Ledge, Michigan, Jeffrey R. Martin

Masters Theses

Pennsylvanian outcrops along the Michigan Basin's southern/margin are composed of fluvial-deltaic and marine shelf sediments. Constructive deltaic facies include point-bar sandstones displaying erosional bases, channel lag, and upward decreasing grain size and sedimentary structures. Cross-stratification data indicate a unimodal, highly variant, northward-trending, paleocurrent pattern that deviates from regional paleoslope. Point-bar sandstones record delta plain deposition by meandering distributary channels. Channel margin facies include Lingula-bearing, interdistributary bay shales; overlain gradationally by laminated, flaser-bedded and rooted marsh shales and siltstones; and subbituminous swamp coal. Bay-fill facies are interrupted by lens-shaped, quartz-poor, fine-grained, crevasse-- splay sandstones.

Delta destructive facies--quartz -rich bioturbated sandstone-- suggest …

The Origin Of Carbonate Cements In Bahama Escarpment Limestones, Katharine D. Fulker

Masters Theses

Limestones recovered from Bahama Escarpment dives (DSRV Alvin, 1978) were expected to contain shallow marine, freshwater, and deep marine cementation since the limestones had been fractured, bored, and cemented at depth. Magnesium and trace element concentrations, carbon-oxygen composition, cathodoluminescence, and petrographic study indicated the presence of all three cement types.

Lithification may have proceeded by allochem deposition, major shallow marine cementation, sparse freshwater cementation leaving porosity, fracturing, and final deep marine cementation leaving minor porosity. According to this interpretation, the pore space remained open for an unlikely 75-115 million years. In an alternative interpretation, pore space is occluded after freshwater …

Nitrate Levels In The Groundwater Of Kalamazoo County, Michigan, William Robert Norman

Masters Theses

Nitrate levels from 1,978 wells were compiled and analyzed to identify areas having levels above the Federal and State Drinking Water Standards of 10 ppm, identify possible sources of nitrate in each area and determine factors that produce high concentrations of nitrate in groundwater.

Eighteen areas in which nitrate concentrations exceeded 10 ppm were identified. County-wide, 465 (23 percent) of the wells for which data were available produced water with nitrate concentrations above drinking water standards.

Septic tank effluent is thought to be the most common source of nitrate in the problem areas. Agricultural practices are also likely nitrate contrbutors; …

The Effects Of Precipitation On The Quality Of Ground Water And Leachate Seeps At A Stabilizing Landfill, Nicholas C. Pogoncheff

Masters Theses

A monitoring program was established at a landfill in Kalamazoo County, southwestern Michigan to determine the effects of precipitation on selected parameters in landfill lechate as surface seeps and ground water. Approximately 280 ground-water and surface-water samples were collected from monitoring wells and leachate seeps during more than 11 precipitation events throughout the summer and fall of 1981 and analyzed for specific conductance, pH, chloride, and iron.

Results of the study indicate that infiltration through the refuse due to precipitation is a major factor in controlling the levels of selected leachate characteristics and that with high infiltration rates concentrations will …

The Features And Significance Of Layering And Shearing Within The Zone Of Mylonitization, Northeastern Idaho Batholith, Jon Michael Hermann

Masters Theses

The northeastern border zone of the Idaho batholith contains a north-south trending zone of myionitized gneiss, schist, and granite-granodiorite. The schist and gneiss contain plagioclase augen surrounded by crushed and recrystallized biotite, quartz, feldspar, + muscovite, + hornblende. The granite grades upward from porphyritic rock into augen-bearing mylonitic rocks interlayered with schist and gneiss.

Ground-Water Flow Along The Total Shoreline Of Austin Lake And Its Environmental Contribution To Pollution Of The Lake, William Thomas Williams

Dissertations

The vertical direction of ground-water flow in Austin Lake was determined by placing minipiezometers along the entire shoreline at fifty randomly selected sites. Ground-water samples were taken at each site and the specific conductivity of the water samples was determined along with the chloride and phosphate content. The data were analyzed to determine if there were any relationships among water movement, chemical content, and the presence or absence of an onshore septic tank. The minipiezometer data show that the primary direction of water movement through the sediment-water interface is downward but may become reversed at localized regions as conditions vary. …