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At least 1,279 records · Page 71Linked to original sources
USGS1965

Plant microfossils of the Hazard No. 7 coal, Perry County, Kentucky

The cooperative mapping program between the Kentucky Geological Survey and the U. S. Geological Survey has yielded a number of interesting and valuable by-products. As a part of the stratigraphic studies involving Carboniferous coal fields, R. M. Kosanke has been involved in a detailed analysis of spore floras from various coal horizons. This study is aimed toward a correlation within the eastern coal field and, eventually, toward more accurate correlations with the western Kentucky coal fields.

Kentucky↗
USGS1966

Plant microfossils from the Fort Union Formation

As a part of continuing studies to provide palynological data from critical sequences for comparative biostratigraphic studies, the microfossils found in two Paleocene samples have been examined and photographed.

Open-File Report↗
USGS1966

Plant microfossils from the Lakota Formation

As a part of continuing studies to provide palynological data from critical sequences for comparative biostratigraphic studies, the microfossils found in a sample of "Pine Needle" coal have been examined and photographed. The assemblage is presented on one plate.

Open-File Report↗
USGS1978

Mallets Creek Marsh, Lake Champlain: A plant-nutrient study

Nitrogen and phosphorus dissolved in the interstitial water of Mallets Creek Marsh sediments supply about 42 percent of the nitrogen and about 9 percent of the phosphorus used by rooted macrophytes within the marsh. These percentages may become larger during middle and late summer, when water inflow to the marsh is reduced and the supply of dissolved nitrogen and phosphorus is diminished. Fluctuations in water-surface level alternately saturate and partially dewater sediments between approximately 98.5 feet and 93.5 feet above mean sea level. Repeated water-level declines to below 98.5 feet through lake-level regulation in spring or early summer could transport interstitial nitrogen and phosphorus from the marshes to Lake Champlain. This would decrease the growth of rooted macrophytes within the marsh and promote eutrophication of the lake.

Vermont↗
USGS1978

Impact of flow regulation and power plant effluents on the flow and temperature regimes of the Chattahoochee River - Atlanta to Whitesburg, Georgia

A calibrated and verified transient flow temperature model was used to evaluate the effects of flow regulation and powerplant loadings on the natural temperature regime of the Chattahoochee River in northeast Georgia. Estimates were made of both instantaneous and average natural temperatures in the river during an eight-day period in August 1976. Differences between the computed average natural temperature and an independent estimate of natural temperature based on observed equilibrium temperatures were less than 0.5°C. The combined thermal effects of flow regulation and powerplant effluents resulted in mean daily river temperatures downstream of the powerplants about equal to or less than computed mean natural temperatures during the period of interest. An independent analysis of historical river and air-temperature data, although considerably less accurate than model computations, provided substantially the same result. The range and rates of change of computed natural diurnal temperature fluctuations were considerably less than those presently observed (1976) in the river. The models also were used to simulate summer river temperatures using estimated year 2000 flow conditions and meteorologic data collected during 1976. Except during periods of peak water-supply demand, differences between computed year 2000 river temperatures and observed present-day temperatures were less than 2°C.

Georgia↗
USGS1979

Water quality of south San Francisco Bay and Coyote Creek after failure of the San Jose-Santa Clara Water Pollution Control Plant I. 17 September - 10 October 1979

Data are presented to document some short-term biological and chemical consequences of a sewage spill in the southern area of San Francisco Bay and its receiving-water tributary, Coyote Creek. Sampling was conducted at fixed U.S. Geological Survey stations in South Bay, and at six new stations in Coyote Creek, on 17, 20, 25, 26 September and 3, 10 October 1979. Measured water-quality parameters were: salinity; temperature; turbidity; concentrations of selected dissolved gases (oxygen, carbon dioxide, methane, nitrous oxide, ethylene, ethane); concentrations of dissolved inorganic nutrients (ammonia, nitrate, nitrite, phosphate, silicate); and concentrations of chlorophyll a and phaeopigments, total coliforms, fecal coliforms, and fecal streptococci. Rates of oxygen utilization and photosynthetic production were measured at selected stations.

California↗