Reports
Reconnaissance survey of the Severn River sediments
1977, Kerhin, R.T.
Information Circular 23
Abstract
A reconnaissance survey of the Severn River Mouth was conducted in December, 1974 to determine the distribution and physical properties of the sediments. The sediments are distributed into two distinct facies separated by a narrow mixed zone. The nearshore facies is dominated by medium to fine grained sands controlled by wave activity and longshore currents. The mineralogy of the sands is mainly quartz with minor amounts of heavy minerals and glauconite. The major supply of sediment to the nearshore facies comes from shoreline erosion of Pleistocene sand and gravel and from the highly glauconitic Aquia Formation. The deepwater facies is composed of fine-grained muds. The bulk mineralogy of the muds is quartz with lesser amount of kaolinite , illite and chlorite. Fecal pellets are present in the sediments and are confined to the areas surrounding the natural oyster bars. From bathymetric comparison of historical charts, the deepwater facies is an area of accumulation Located in the main river channel and along the eastward edge of the river mouth. Sediment in the deepwater facies comes from the Chesapeake Bay and is controlled by seasonal variation of the estuarine circulation pattern in the Bay.
