Paleontology's determined pursuit of the elusive mosasaur - the 'T-Rex' of the ancient ocean - took a new turn last summer when nearly 100 eco-tourists descended on the Pembina Gorge in northeast North Dakota to become amateur scientists digging for fossilized marine bones.

Unique to this enterprise was the genuine welcome of people of nearly all ages and stages of life. No previous excavation experience was required. The only real requisite for those who signed on was a willingness to learn and a determination to dig.

Leading the 10-day program was Dr. John Hoganson, paleontologist with the North Dakota Geological Survey in Bismarck, and Melanie Thornberg, owner of Dakota Adventures in Walhalla, N.D. Their efforts combine to ensure the week's guests are well prepared and well cared for as they experience their adventurous dreams. In turn, their guests' "vacation" efforts contribute to the excavation of valuable fossils for the Geological Survey and to tourism development in the gorge.

Teen-agers and grandmas, lawyers and college students all begin their dig at the same place - a short classroom hour at the Forestwood Inn in Walhalla.

"Most of the people who come on these digs have never done this before," says Hoganson. "We take part of the first morning to explain how to dig and what they should be looking for. Some are afraid of destroying the bones. We talk about that a little bit. I usually tell them we've all broken things at times. That's why they made Superglue."

Hoganson's directions give each excavator a short course on what to look for when sifting through the rock layers and how to dig out fossils successfully.

Cyndy Lewis, a psychologist from St. Joseph, Mich., on her first dig in North Dakota, says, "They explain everything from A to Z. It makes you feel really comfortable. And they don't make you feel like some kind of dodo. Next year if I can, I'll bring my son back here for another dig."

By mid-morning of the first day, each group is standing on a carved ledge on a shale hillside overlooking the peaceful Pembina Gorge ready to dig up some bones. Thornberg is busy handing out materials and chatting with group members. "Don't forget hats and sunscreen," she says as she works through the lineup. "And remember, no bones, no food!" Amid the laughter and friendly banter, the work gloves, kneeling pads, brushes, picks, trowels, miniature shovels and other tools are passed around. Finally, the dirt begins to fly.

An air of excitement and expectation brings each group together in a common quest for scientific experience. Somewhere deep beneath the shale - or perhaps as close as their fingertips - lie fossilized remains of marine life from more than 80 million years ago. The excavation site is located near the edge of the ancient Pierre Sea, part of a vast, Cretaceous period ocean once covering most of North Dakota. The site overlooks the Pembina Gorge, a deep valley cut by the Pembina River through Cretaceous rock and glacial sediments laid down during the last ice age.

As digging goes deep and group members get to know each other, conversation along the ledge ebbs and flows. Chatter includes bits and pieces about kids, neighborhoods and work mixed with jargon related to digging. "I found a tooth thingie!" calls one young digger.

"Some bone has been found down here, if you want to look at it," confirms Hoganson. "It could be part of a mosasaur jaw line."

With that some of the group resumes digging with renewed vigor. "I already found a vertebrae!" says 10-year-old Kelsey Leake of Emerado, N.D. Kelsey, her brother, Kelby, and their mother, Diane, came on the dig because "these kids have been into dinosaurs since they were old enough to talk." Others, like Lewis, continue to pick away at the hillside in a more relaxed fashion. Says Lewis, "I don't really care if I find anything...at least I'm not working. I'm not at my desk."

While his diggers are at work, Hoganson continually moves back and forth along the ridge, stopping to talk, lending advice and keeping everyone focused. "Most of the people who come on these digs are very interesting people," says Hoganson, "so it's a lot of fun not only to talk about this work, but their work too."

"It's also important for me to talk to the people here about what they're seeing. I try to tell them about lots of stuff, not just the fossils, because that keeps the interest up when they're not finding the bones they're looking for. We talk about how all of this got here, about the action that deposited it here, anything that's helpful in developing an understanding of what they see."

All fossils found on the excavation site are wrapped and bagged for transport to the Geological Survey offices. Their winter tasks will be to sort through everything and identify significant material.

These excavators have come from all parts of the United States, Ontario and even Norway. A few have some experience on archeological digs elsewhere in the U.S., but most are novices. Several of this year's group had taken part in the first Pembina Gorge dig in the summer of 2000. Steve Ziegler of Bemidji, Minn., and Kathy Garceau of Garland, Texas, were both part of the first dig and returned to try to top their discovery of a 12-foot-long, giant squid.

A combination of public and private groups working together gives both eco-tourists and the state the maximum opportunity for a successful adventure. The 2001 summer dig was a coordinated effort between North Dakota's Game and Fish, Parks and Recreation, and Tourism departments, the Geological Survey and Dakota Adventures. The Game and Fish and Parks departments own and manage the land on which the dig is held. Geological Survey personnel like Hoganson and Johnathan Campbell provide expertise. "But one of the main reasons this all works is because of Melanie," emphasizes Hoganson.

Thornberg is the local contact who brings a high level of fun and excitement to the dig. She is the organizer keeping everyone comfortable and happy no matter what the situation is. Long before people begin their journey to Walhalla they get letters and e-mails to update them on the progress of the tour. Tammy Fischer of Devils Lake, N.D., who brought her three sons, explains, "I read about it (the dig) in the paper and said, 'I want to be there.' I booked us in last year and kept in contact with Melanie through e-mail ever since."

Dakota Adventures' guests get constant information on what to expect while digging, what kinds of activities they can take part in while staying in the northeast corner of the state and what they can do for entertainment during the evenings or when it rains. Thornberg helps line up hotel or camping accommodations and, of course, the food.

Make no mistake, food is an essential element to the success of an eco-tourist activity. Under a screened canopy set just below the digging ledge, Highway 32 Diner owner Nancy Belanus serves a noon feast every day of the excavation. A wide variety of specialty salads and sandwiches, coupled with fresh fruit, juices, sodas and bottled water, keeps everyone refreshed through even the hottest days.

The crowning glory is the homemade Juneberry pies made by local baker Adrienne Wellman of Cavalier, N.D. As Belanus arrives and pies begin to appear from the back of her van, someone on the ledge spies the activity and yells, "Once you've had a piece of that pie, you're gonna feel like a new person!" Ziegler, also an apparent veteran pie eater, leaves his pick and hurries down the slope. "I feel like George Bush right now," he quips. "God bless the pie lady!"

At the end of the day, many adventurers check out activities of interest in the surrounding area. Some take in live theatrical productions, visit museums or historic sites or check out local shopping opportunities. Others take advantage of scenic areas in the Pembina Gorge or its recreation. Summer activities include hiking, fishing, floating down the Pembina River in tubes or canoes, golfing on several top golf courses in North Dakota and Manitoba, or spending time at nearby lakes.

This dig was divided into one-, two- and three-day sessions. Young people over the age of 11 were welcome during the regular digging week. A "Kids' Day" was added to the schedule, allowing those 11 and under to dig when accompanied by an adult. A dozen families filled up the kids' day slate soon after it was advertised.

This summer in mid-July a nine-day archeological dig is planned near Marmarth in extreme southwestern North Dakota. A shorter weekend dig in the Pembina Gorge is planned Aug. 3-5. Kids' Day is Aug. 5. The dig site is about 10 miles west of Walhalla.

For more information or to make reservations for the fossil digs, contact Melanie Thornberg, Dakota Adventures, Box 400, Walhalla, ND 58282; or e-mail walhallafossildig@hotmail.com. You can also call 701-549-2627 or 701-549-3939.