MOAB, Utah, Feb. 5, 2002 - The Bush administration is opening the red rock country near two of Utah's popular national parks to oil and gas drilling, over the objections of some park rangers in the Southwest and government scientists.

As part of the president's energy plan to expand development on federal lands, 50,000-pound trucks have been pounding the ground between Arches and Canyonlands National Parks, searching for oil with seismic measuring instruments. At the same time, oil companies have bought leases to drill on federal land outside Canyonlands park.

Administration officials say visitors to the parks will barely notice the changes to the land, while national park scientists say the land could take decades to recover from the shock waves of the industrial hammerings.

Oil derricks and drilling equipment have long been a feature on the nation's public lands, with nearly 35 million acres open to development. During the Clinton years, oil and gas leasing increased considerably over previous administrations. But areas considered wilderness and areas near national parks were usually off- limits.

The Bush administration has been pushing federal land managers to speed up development, which includes work within two miles of national parks, as is happening here. Federal land managers who control the scenic Utah lands have been told that energy development is now the top concern.

``Utah needs to ensure that existing staff understand that when an oil and gas lease parcel or when an application for permission to drill comes in the door, that this work is their No.1 priority,'' Bureau of Land Management supervisors wrote to field officers in a memorandum a month ago.

This week, as President Bush unveiled his budget, Interior Secretary Gale A. Norton requested new financing to streamline permits and study sites to drill on federal lands. Ms. Norton said the new exploration could be done with minimal environmental damage.

But national park officials say they are alarmed as the exploration trucks and drilling equipment have come close to their borders. The parks around this town, a mountain- biking mecca on the Colorado River, had huge increases in visitors over the last decade.

To protect the sandstone spires and the living surface layer that covers the red rocks of Utah's canyon country, the Bureau of Land Management has repeatedly urged mountain bikers and off-road vehicle users to tread lightly and stay on the main roads. At the same time, the bureau, the nation's biggest land manager, has given the go-ahead for trucks to crisscross thousands of acres of roadless desert soil, looking for oil.

Park officials said that drilling equipment near Canyonlands National Park will mar the view, and that the tracks from exploration trucks could lead to new off-road vehicle use in areas where officials are trying to limit intrusion. Federal scientists expressed similar concerns about exploratory ventures set to begin this month outside Arches National Park, site of the signature Delicate Arch that adorns Utah license plates.

``Our concern is with visibility issues and road construction,'' said Bruce Rodgers, the chief of resource management at Canyonlands National Park. ``You would be able to see these roads, platforms and pumps from the park. And the soil is quite fragile.''

The Bush administration is also preparing to sell new leases next month around the San Rafael Swell, a curtain of rainbow-colored cliffs which Gov. Michael O. Leavitt, a Republican, has proposed setting aside as a national monument.

Officials with the Bureau of Land Management, which controls one- eighth of all the land in the United States and 22 million acres in Utah alone, said that the oil development would be done in such a way to minimize what recreational users see on the land and that the oil companies would have to restore the land near the parks when the work was completed.

``You won't see it looking like West Texas with oil pumps everywhere,'' said Bill Stringer, the deputy field manager of the bureau office here. ``The drilling will be spread out, and in some cases we'll get them to turn the drills sideways so you can barely see them from the parks.''

The door to new drilling and exploration on public lands has opened just as the price of energy and natural gas has plummeted. When the president issued his energy plan a year ago, with increasing drilling on public lands in the West and in the Arctic National Wildlife Refuge as a centerpiece, gas and oil prices were high. They are now at a level that gives some companies little incentive to proceed beyond exploration.

``Last year everybody was geared up for a boom,'' said Neil Stanley, a vice president of Forest Oil, which has numerous oil-drilling leases on public land in the West. ``The old bumper sticker slogan - `Lord, please give me one last boom and I won't let it get away' - that's how people felt. But now, the prices are causing me to wonder what I'm doing.''

Officials at another oil company expressed surprise that the Bush administration was selling leases in scenic areas so close to Canyonlands National Park.

``We're all just sort of shaking our head because this area is so controversial,'' said Beth McBride, president of Legacy Oil, which owns a lease that allows it to drill for oil in the Lockhart Basin next to Canyonlands National Park. The area, which had been considered for wilderness protection and part of an expanded national park, is habitat for bighorn sheep and other rare species. Scientists say the animals depend on the delicate soil for nutrients and water that comes from springs on that land.

``Although the Clinton administration certainly wasn't shy about issuing leases, they were much more careful to avoid scenic and unique landscapes like southern Utah's,'' said Heidi McIntosh of the Southern Utah Wilderness Alliance, an environmental group based in Salt Lake City.

Two months ago, environmental groups sued the federal government for its lease sales near Arches National Park and nearly a dozen other areas in the Rocky Mountain West.

Ms. McBride, whose company owns a lease to drill in the contested area outside Canyonlands, agreed with parts of the lawsuit.

``I'm kind of with them,'' Ms. McBride said in an interview. ``They shouldn't tell us we can come in and drill if they haven't cleared up all the environmental issues.''

The park staff at Dead Horse Point State Park, a popular site between Canyonlands National Park and Arches, urged the government to deny a permit for oil companies to do seismic exploration in the area. These exploratory probes are part of decades-old search for oil throughout the interior West. The region is rich in natural gas, and there are oil deposits of uncertain size.

A United States Geological Survey expert on soil damage, Dr. Jayne Belnap, wrote bureau officials last year, warning of long-term damage from new exploration near Canyonlands National Park. It could take up to 250 years for some of the dry soil around the park to recover from the heavy exploration equipment, Dr. Belnap wrote in a memorandum.