Mid-Continent Geographic Science Center

Promises and challenges of data collected to aid the St. Louis Area Earthquake Hazards Mapping Project

The St. Louis Area Earthquake Hazards Mapping Project is a study of the U.S. Geological Survey. The study includes collection of geotechnical data from other sources to assist with subsurface characterization in the project area, which encompasses approximately 1,711 square miles (4,432 square kilometers) of Missouri and Illinois (fig. 1) within the St. Louis Metro area. Data sources include the U.S. Army Corps of Engineers, the Missouri Department of Transportation, and engineering firms. Interpretation of these data will aid the prediction of site response at various localities throughout the project area and the production of seismic hazards maps based on scenario earthquakes affecting the region. More information...

Hydrologic Investigations Concerning Lead Mining Issues in Southeastern Missouri

The dam for Clearwater Lake was completed in 1948 and reservoir filling began at that time. Lead and zinc mining operations along the Viburnum Trend Subdistrict began in the Black River Basin in 1966. Arsenic, cadmium, cobalt, copper, lead, nickel, and zinc are the major trace elements associated with the sulfide minerals of this Mississippi Valley Type ore deposit. Clearwater Lake may be a sink where these mining-related trace elements accumulate and are stored.

Sediment cores were collected from six sites in Clearwa­ter Lake to spatially and temporally characterize the concen­tration of trace elements in the bed sediment. The Clearwater Dam site core is the only core that is known, with certainty, to have penetrated to the pre-impoundment (pre-1948) surface. The core from Logan Creek probably penetrated the pre-min­ing (pre-1966) surface; the lower Black River core penetrated the pre-mining surface based on lead-210 isotopic analysis. More information...

Rolla, Missouri