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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↗

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↗

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↗