HUNTINGTON — The first call about a collapse at the Crandall Canyon Mine three weeks ago was made almost an hour after the accident. And it came from the University of Utah seismograph station, not workers or bosses at the mine.

Mine workers called three minutes after Walter Arabasz, the director of the U. seismograph station, called 911 in Emery County. The dispatch recordings were provided to media on Monday by the Emery County Sheriff's Office.

Those details emerged as the families of the six trapped miners were told that work on a seventh drill hole had been delayed because of bad weather. Additionally, a plan to lower a robot into the mine through a previously drilled hole was stalled because of debris in the hole. The hole was drilled almost two weeks ago.

Officials refused to say whether the work had resumed Tuesday morning. U.S. Labor Department spokesman Matthew Faraci said any new developments would first be reported to families of the trapped miners.

On the 911 recordings, Arabasz told Emery County emergency dispatch that readings near the mine at 2:48 a.m. Aug. 6 showed an earthquake of about 4.0 magnitude on the Richter scale. (That was later revised to 3.9.) Although he did not say it was caused by a collapse, he told the dispatcher it looked like it was connected to something that happened in a mine.

"Just from the general character of the seismic event, it looks like it might be a coal mining-related event," Arabasz told the dispatcher.

During the two-minute conversation, Arabasz asked if the dispatcher had other reports of "the event." The dispatcher told him there were no other reports.

At 3:47 a.m., a worker at the mine, Mark Toomer, called to report a collapse. He did not say there were injuries or ask for additional rescue personnel but simply suggested that they start an ambulance up the canyon toward the mine.

"We had a big cave-in up here, and we're probably going to need an ambulance," he said on the recording. "We're not sure yet, because we haven't heard from anybody in the section. But we're most likely going to need one up here."

The collapse filled the mine shaft where six miners were working with rock and coal, although it is not known if the miners were buried. Those six men — Kerry Allred, Don Erickson, Luis Hernandez, Carlos Payan, Brandon Phillips and Manuel Sanchez — have not been heard from since that morning.

Rescue efforts have been suspended since Aug. 16, when another cave-in killed three rescue workers.

The call from Arabasz further contradicts mine owner Bob Murray, who maintains the collapse was caused by a seismic event, not caused by the mine.