The Division’s Nashville office covers Middle and West Tennessee. It is organized into mapping, subsurface geology, technical support, and West Tennessee. A regional office in Knoxville serves East Tennessee.
Division activities includes geologic hazards research, public service, education programs, basic and applied research on geology and mineral resources, and publication of geologic information. The Division’s subsurface section maintains a well cuttings and core sample library and oil and gas drilling and production records on more than 10,000 wells drilled in the state since 1868. The Division keeps up-to-date well location and field maps, and researches subsurface stratigraphy and structural geology to provide basic geologic information. It also publishes the resulting maps, charts, and cross sections, and makes them available through the technical support section’s maps and publications sales office.
Geologic mapping is an important function of the Division. The mapping section performs basic geologic mapping, and mineral resources identification, evaluation, and mapping. Mineral resources information is published in a mineral resources summary that accompanies each published geologic quadrangle map. Also included is information about geologic hazards such as caves, landslides, and sinkholes. There are 804 7.5-minute quadrangles covering Tennessee. These map units are at a scale of 1" = 2,000' and cover an area of about 60 square miles. Since 1960 the Division has mapped and published 487 quadrangles, placing Tennessee among the top five states in the nation in terms of percentage of quadrangles mapped (over 60 percent) at this scale.
The Division also devotes considerable effort to coal-related research. Geologic mapping in the coal field region, collection of reserve data, collection of samples for analysis, publication of reports, and processing data for entry into a computerized data base make up most of the coal-related program. These efforts have been enhanced in recent years through cooperative efforts with the U.S. Geological Survey. A large amount of unpublished coal data is also available to the public.
Tennessee’s undeveloped energy resources, including lignite in West Tennessee and oil shale (also a potential low-grade source of uranium) in Middle and East Tennessee, have also been given some attention in recent years. Surface mining of lignite has potential impact on ground water resources, so the Division has been working with the U.S. Geological survey to assess problems that might arise. If mining the black shale for oil and/or uranium becomes feasible, the Division will be able to make use of a large file of existing outcrop maps and subsurface data.
The Division’s effort in support of the construction materials industry is mostly in the form of the mineral resources summaries that accompany individual geologic quadrangle maps. However, individual commodities are occasionally the subject of statewide studies.
Traditionally, mineral resources work has had top priority among the Division’s activities. However, increases in public awareness of the importance of protecting the environment and of dangers posed by geologic processes has required modifying priorities in recent years. Earthquakes, floods, landslides, and sinkhole collapse pose threats, and weathering and erosion produce unstable materials that complicate excavation and construction, and threaten completed structures. Part of the Division’s public service activity involves responding to requests for field inspection of these various types of geologic hazards. These average about 40 per year.
The West Tennessee section has also been cooperating recently with the U.S. Geological survey and other state geological surveys to produce 1:250,000-scale seismic hazard maps of West Tennessee. In addition, the Division maintains a seismic station at its core storage and research facility at Waverly, Tennessee. This station is part of a national seismic network designed to improve earthquake monitoring in the New Madrid Seismic Zone, the most active seismic area in the United States east of the Rocky Mountains. It is operated under a cooperative agreement with the U.S. Geological Survey National Earthquake Information Center and St. Louis University. The station consists of a three component seismometer, a 24-bit acquisition system, and a satellite system with digital processing unit for transmitting data to Golden, Colorado. The system is accessible by computer dial-up, and has onsite storage for 14 days of continuous data.
The Division maintains active educational and public outreach by furnishing speakers on Tennessee geology, mineral resources, and geologic hazards to schools, civic groups, and other interested organizations. These typically number about 20 per year, and affect more than 1,000 individuals.
