Jolie Lee

USA TODAY Network

An exploratory dig for Los Angeles' subway extension project has uncovered Ice Age fossils.

The discoveries so far have included geoducks (large clams), sand dollars and digger pine tree cones and seeds, and a rock that "appears to have a sea lion skull within it that is perhaps two million years or more old," according to the Metro Rail's blog.

The expansion of L.A.'s purple line is near the La Brea Tar Pits, where many fossils have been found.

The exploratory shaft for the subway route is now 65 feet deep, according to Metro.

"We expect that we're going to find large deposits of late Ice Age vertebrate remains," said Aisling Farrell, collections manager at Page Museum at the La Brea Tar Pits, in an interview with KABC-TV in Los Angeles.

Metro is working with the museum to identify and preserve the fossils, according to Metro.

The purple line extension will allow passengers to ride from downtown L.A. to the westside in 25 minutes. Currently, it take up to 1 1/2 hours by car, reports KABC.

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