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| State Geologist Charles Smith |
Tomorrow – March 18 – marks the 19th anniversary
of one of the most unusual events in Conecuh County history, the appearance of
the “Mystery Crack” in the Springhill community near Repton.
This so-called “Mystery Crack” appeared during the early
morning hours of March 18, 1997 on Conecuh County Road 73, about 4.8 miles east
of Repton, in the Springhill community. In a front-page story in the March 27,
1997 edition of The Courant, the newspaper called this crack an “unusual
geological condition” and noted that a thick, slippery layer of clay was to
blame for the crack.
Billy Mims, who was Conecuh County’s Emergency Management
Director at the time, said that the fault line appeared sometime between 5 a.m.
and 6:30 a.m. on March 18, which was a Tuesday, and that it continued to grow
bigger and bigger. As of March 27, the crack was 300 yards long and was as much
as 60 feet wide in some places. Mims also noted that the crack was very deep in
some spots, having varying depths of from five to 23 feet.
The “mystery crack” caused two cracks to appear across
County Road 73, which runs from Belleville Street in Repton to County Road 7,
near Springhill Church. Those cracks were about 35 feet apart and prompted
county officials to close the road by putting up barricades to prevent vehicles
from traveling through the area.
This, however, didn’t stop curious sightseers from visiting
the scene and bypassing the barricades to get a closer look. State Geologist
Charles Smith investigated the incident and cautioned citizens about visiting
the site, calling it “foolhardy” because even experts had no idea how stable
the area was at the time. Mims agreed and pointed out that the road had dropped
and was a hazard to cross.
Mims called the State Geological Survey in an effort to
determine what caused the “mystery crack” and to see if anything could be done
about it. The Alabama Department of Transportation was also called in to
conduct drilling for core samples and to monitor the problem.
Smith told newspapers that clay beneath the road was to
blame. “We did the first boring about 15 feet above the upper crack in the road
and went through gravel and at about 15 feet, hit a slick, water-saturated
clay. Drillers hit the limestone bedrock at about 31 feet.”
The second bore hit the limestone layer at 85 feet, and the
slippery clay layer was again found between the gravel and limestone.
“The mystery lies in why you have limestone at 30 feet in
one place and 80 feet at another,” Smith said. “It is highly irregular. We have
a fault; it is a very old fault and it did not move during this happening,
although it may have presented an opportunity for the movement.”
Smith said that he had not seen a geological formation quite
like this ever before and said it was “absolutely exciting for a geologist.”
Smith also noted that the appearance of such cracks was highly unusual and that
it was likely that local residents would not see it again in Conecuh County in
their lifetimes.
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