‘Mystery Crack’ appeared near Repton, Alabama 27 years ago

State Geologist Charles Smith

This week marks the 27^th anniversary of one of the most unusual events in local history, the appearance of the “Mystery Crack” 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. Newspapers at the time 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 locally in their lifetimes.