Welcome to the Crisfield, MD, Deep Geothermal Test Site Homepage. Here you will find details of how the site was selected, the deep drilling program, and results. As shown on the following plots of temperature versus depth, this site was selected for a deep geothermal test because 1) it indicated reaching the highest temperatures at the shallowest depths, and 2) there was a potential space-heating application nearby.
|Geophysical logs of deep geothermal test at Crisfield|
|Table of temperature values||Plot of temperature values|
|Table of density values (gm/cm3)||Plot of density values|
|Sonic log values (usec/foot)||Plot of velocity values (Km/sec)|
Limited aquifer tests were conducted within three zones of the Patuxent Formation by Gruy Federal, Inc., and interpreted by The Johns Hopkins University. The zone shown in the table below was selected for detailed analysis after preliminary testing due to its greater productivity and generally more reliable and complete data. The values shown were reported by K. Yu at the Geothermal Energy and the Eastern U.S. Technical Information Interchange Meeting at Berkeley Springs, WV, on October 30-31, 1979 in a presentation entitled "Crisfield, Maryland, Well Characteristics Determined Using All Test Data". No detailed information concerning the methods used to arrive at the values listed have been published.
|Some Geothermal and Hydrologic Parameters Over the Depth Interval 1,189.3 to 1229.3 meters|
|Storage coefficient||3.9 X 10-3|
A more comprehensive analysis was provided by Laczniak (1980) as an M.S. Thesis in the Virginia Tech Department of Geological Sciences entitled "Analysis of the relationship between energy output and well spacing in a typical Atlantic Coastal Plain doublet geothermal system", 100 pp. Laczniak used an "integrated finite difference" numerical model developed by Lippmann and others (1977) to simulate pumping and re-injection in a typical Atlantic Coastal Plain geologic setting. The interested reader is referred to this Thesis to see the results of thermal and fluid-flow fields for a 3-dimensional rectangular liquid-dominated low-temperature system. Laczniak concluded:
"The overall results quantify the potential usefulness of geothermal resources within the Atlantic Coastal Plain. A rested doublet system with similar hydrologic and thermal conditions as those encountered at the Crisfield, MD, geothermal test site, a well spacing of 1,000 meters, a permeability of 100 md, and a pumping-injection stress of 500 gpm (injection temperature 43.5oC could produce 5.5 million Btu's per hour over a period greater than 30 years."
There were other sites in the southeastern U.S. that would have yielded higher temperatures at deeper depths where the wedge of Coastal Plain sediments was thicker than at Crisfield. For example, the temperature at a depth of 300 m at Stumpy Point (Hole C-19) in North Carolina was 26oC, similar to the value of 27oC at Crisfield (DGT-1), but the thickness of water-saturated sediments at Stumpy Point is greater and so a deeper hole would encounter higher temperatures if the hole went all the way to basement; however, although the temperatures at greater depths (there is a thicker sedimentary insulator there) would have been more attractive as a geothermal resource, there isn't much around Stumpy Point to offer as a space-heating application, and that, as well as temperature, was a prime consideration in the eventual selection of Crisfield, MD, for the deep geothermal test.
Some pictures courtesy of Wilson McClung.
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Last updated: 4/19/2006