Odd landforms on Mars intrigue scientists

SEATTLE, March 22 (UPI) -- Odd landforms observed on the martian surface are unlike anything previously seen and could be clues to the planet's geological history, U.S. scientists say.

Geologists at the University of Washington in Seattle have dubbed the strange formation periodic bedrock ridges, saying they look like sand dunes but are, in fact, rock.

"These bedforms look for all the world like sand dunes but they are carved into hard rock by wind," said David Montgomery, a UW professor of Earth and space sciences, said in a release Thursday. "It is something there are not many analogs for on Earth."

Montgomery said he believes the ridges are composed of a softer, more erodible material than typical bedrock and were formed by an unusual form of wind erosion.

High surface winds on Mars may be deflected into the air by a land formation, he said, and erode the bedrock where they settle back to the surface.

Spacing between ridges is determined by the strength of the wind, the size of the deflection and the density of the atmosphere, he said.

The eroded rocks could be revealing some of the past geological history of Mars, Montgomery said.

"You could actually go back and look at some earlier eras in martian history, and the wind would have done us the favor of exposing the layers that would have that history within it," he said.

"There are some areas of the martian surface, potentially large areas, that up until now we've thought you couldn't really get very far back into Mars history geologically."