Human footprints found embedded deep under the sands of the hot, high deserts east of Los Angeles may touch off further explorations of an area that hitherto has been almost completely bypassed by archeologists.

The rare footprints, which may be more than 4,000 years old, are part of an artifact-rich site being excavated this summer along the banks of the Mojave River by a team of archeologists from the University of California at Riverside.

The archeologists working this site believe the footprints may help attract interest to the wealth of information surfacing from what was, in less arid prehistoric times, a heavily populated area.

Now the vast deserts east of the San Bernardino Mountains are home to a few cities, a network of powerlines, seas of cactus, countless lizards and rodents, and very little water.

"This whole region was a major route for commerce," says Nelson Leonard, assistant director at the San Bernardino County Museum, "but we don't know anything about the changing cultural affiliations and habitation patterns that took place here.

"The Majave River Basin is probably equivalent to the major drainage areas in the southwest, such as the Little Colorado River, but not much attention has been paid to it," he says. "That may be changing."

The footprints - which are just now making news in the archeological community - number 60. Four sets of the prints are "in stride" with one another, and there appear to be four categories of size - two small, one medium, and one large. They were found in association with some animal tracks, and the smaller sets of prints, apparently children, appear to be scurrying about.

Charcoal taken from the layer of earth just above the footprints suggests the impressions are at least 4,000 years old, but project director Carol Rector is seeking some datable identification below the prints to more closely "bracket" their age. So far, she says, "all we have found is beach sand."

Workers have uncovered projectile points, beads, quartz drills, pestles and mortars, small awls, chipping waste, bone fragments and other cultural materials.

After the archeologists finish their work at the site, a year or more of laboratory work will result in some initial answers - and very likely more questions - about which prehistoric peoples left behind the remnants of their existence.

The future of the footprints, however, is unclear. Techniques to salvage such prints are not refined. Although workers have made casts of the impressions, Rector is seeking expert advice on how best to preserve the find.

Because the site was known to have some archeological significance, the Victor Valley Water Reclamation Authority was compelled by law to have it surveyed by experts before building a federally funded water treatment plant on it. The university was given a $135.000 contract to examine the property and develop its archeological potential.

After the footprints were discovered, the water authority's attitude changed from reluctant to interested, said Rector. She added that since the construction budget for the treatment plant is $2 million and under the law up to 1 percent of that is available for archeological work, she may ask for an additional $65,000 to complete the work with the prints.

She says she is optimistic that they can somehow be preserved.