While many Alaskans were uneasy during Sunday's magnitude-7.1 earthquake, most had the security of being at home, close to family and near reliable Internet and phone lines to find out exactly what happened and where the worst damage occurred.

However, some mushers, including those competing in the weekend's Northern Lights 300 Sled Dog Race from Big Lake to Finger Lake and back, did not have such modern conveniences.

"It was the longest two minutes of my life," said Karin Hendrickson, 45, of Willow. The four-time Iditarod finisher is still recovering from a broken back suffered when she was hit by a car while training her team along the Parks Highway in 2014.

Hendrickson described the ground thrusting under her while mushing in inky blackness along the Yentna River — 13 miles from the next checkpoint and more than 40 from the finish line — as truly terrifying.

"One of the last places I want to be during a 7.1 earthquake was running dogs down the middle of a frozen river," she said.

Hendrickson said she was stopped and bent over a dog, slipping on booties, when the shaking began. Already a couple of days into the 300-mile race and exhausted, she initially thought she might have been suffering from sleep deprivation, known to cause hallucinations in some mushers. But within seconds, she realized the situation was real and possibly life-threatening.

"The ice was rippling and waving like a waterbed when someone jumps up and down on it," she said. "I was having a hard time keeping my feet. As the ice rolled and jumped, it cracked and snapped all around me. Water came shooting up through the cracks, and I was trying to figure out if we were all going to wash away."

Hendrickson looked at the bank nearest her, but the incline was too vertical to consider scaling it. She scanned her surroundings, saw some driftwood nearby and figured it might be lodged on a gravel bar — a much safer place than river ice.

"I was trying to figure out how to get the dogs there, as they were too riled up to follow directions at that point. I was just about to try to shuffle and drag the dogs in that direction when things started to calm down," she said.

Once the ground stopped shaking, there wasn't anything Hendrickson could do but continue on, so she did — hyper-vigilant of hazards that may have been created by the upheaval.

"I was definitely watching the trail for any open leads," she said. "There was one area that had a small open lead on the way up (river) the day before. This time on the way down there was a lot of open water and big slabs displaced and broken free."

Hendrickson gave this section wide berth.

Farther back at the Yentna Station, 214 miles into the race, Mari Troshynski, 30, of Willow, had just pulled into the checkpoint when the quake hit. The first indication of something odd came when her dogs, which should have been weary at that juncture, suddenly sprang to their feet and began acting odd. Seconds later, she heard what she described as a sonic boom.

"That's what it was like, something you could feel as well as hear, and then everything was rolling," she said. "I know earthquakes can roll, but being on the river, I think we felt the water moving around us and under us."

As it went on and on and Troshynski began to hear ice cracking underfoot, she started wondering if she should try to get her dogs, as well as the other eight teams parked nearby, off the ice and up the bank.

"I wondered how deep the water was below us and began to imagine … a pretty horrible demise," she said.

Fortunately the quake stopped, and after Troshynski's heart stopped thumping she went into the cabin at the checkpoint and got a couple of hours of rest. As she slept, race staff went ahead on snowmachine to ensure the trail was safe. Once she was back on the trail, Troshynski realized how grateful she was for their efforts.

"As we were going along, there was suddenly a heavily marked section of the trail, with a lot of Xs (made from wooden lathes), which usually signify some obstacle or danger in the trail. In my sleep-deprived state, all I could think was, 'This wasn't here on the way out.'

"Then the dogs disappeared, and I followed, diving down a sharp drop, which I realized, mid-descent, was a section of river that had cracked and maybe risen in a series of jagged chunks, which the machines had negotiated a narrow trail over," she said.

Other less-extreme evidence was visible on Flathorn Lake farther along the trail, Troshynski said.

"The whole ride back, any body of water we crossed, small or large, had cracks lined with mud. It was an astonishing testament to the violence of the quake," she said. "I felt almost privileged to see it. How many people get to witness such an unexpected result of the Earth moving?

"We notice the things that fall off our shelves, but out in nature, in the quiet and cold, things have changed too."

Back at the Talvista checkpoint, 166 miles into the race, Meredith Mapes, 22, of Knik, was already having a hard time sleeping. The Northern Lights was the young musher's first 300-mile race, so her adrenaline was already running high.

"Just as I was drifting off to sleep, the earthquake hit," she said. "I opened my eyes when it started, and it started shaking harder, so I sat up, and it kept shaking, so I put my feet on the floor and said 'Holy sh*t.' "

As the quake came to an end, a checker came in to tell Mapes and another resting musher that their dogs down on the ice were frightened but otherwise fine, so she again tried to sleep.

"I was exhausted, so it was pretty easy to get to sleep once the adrenaline wore off," she said.

Mushers far from the Northern Lights course felt the earthquake's effects, too. To the north in Chistochina, a checkpoint for the early January Copper Basin 300 Sled Dog Race, other mushers were avoiding new natural obstacles.

"The earthquake caused several ice bridges on our river trail to cave and channel ice sunk like it does in April. The glacial water, which is low right now, is running on top of the ice," said musher Darrin Lee, who along with his wife, Heidi Sutter, uses the Chistochina trails to train their teams for Iditarod and the Yukon Quest 1,000-mile races.

Farther to the south, mushers in the Kasilof area also saw the lakes they train on crack into large jigsaw puzzles of ice.

Joseph Robertia is a freelance writer living in Kasilof with his wife, Colleen, and daughter, Lynx, where they operate Rogues Gallery Kennel and have run several mid-distance and long-distance mushing races.