Construction workers in Santa Cruz, California stumbled upon a whale fossil while working on a major construction project.

As per the regulations in California, a paleontologist should be on the site when major earth moving for any big construction project is underway.

The fossil is relatively intact and major parts have been recovered without causing any harm to the fossil.

The fossil, discovered by a paleontologist on September 4, is a 4-million-year-old fossilized skeleton of whale, according to a report of Santa Cruz Sentinel.

The report said the fossil was found by the paleontologist while monitoring a housing development in Scotts Valley. Scott Armstrong, a researcher at a Los Angeles-based archaeological consulting service Paleo Solutions, said the discovered remains are of a mysticete whale, which is also known as an ancestor of the baleen whale. Armstrong estimates the fossil length at approximately 25 feet.

During the excavation, a team of archaeologists unearthed some skull pieces, jaw, arm bones, shoulder blades and vertebrae. The site where the fossil was discovered is on a mountain, and discovering whale fossil on mountains is very uncommon. But while talking to Santa Cruz Sentinel, Armstrong said the whale’s remains made their way on to mountains through quakes, or movement of tectonic plates.

According to Armstrong, “Most places where you see a hill, somewhere there's a fault line nearby pushing it up. They're relatively inactive faults. But yeah, it's from lifting thousands, maybe millions of years ago”.

The paleontologist found the ancient fossil on September 4, but the process to unearth the skeleton started on Thursday. The paleontologist team used shovels, hoes, brooms and some other tools to excavate the ancient fossil.

After the excavation process, the remains were encased in plaster. Now, they will be transferred to Monrovia offices of Paleo Solutions for further investigation.

Many a times, people digging in Scotts Valley have reported finding shark teeth and marine fossils. Matthew Clapham, a paleontologist at UC Santa Cruz, said, "I think of the fossils you get along the coastline, it’s more common to get a piece of the skull or the brain case or some bones."