Ge11a Field Trip: Sunday 10/28/01

While looking for possible locations of a thrust fault and boundaries between certain rock types (brown metasediment, white lakebed, blackish basalt), we ran into some interesting looking red rocks (carbonate). Here is Glenn, with his rock hammer. I should also mention that at this point we are on the other side of a barbed wire fence from our bus.

The same red carbonate, only this time with soem white metasediment that must have flown around the red rocks, and grey-black basalt.

On the other side of the small dry creek bed from the past features was a hillside with a sharp boundary between some granodiorite and some planed carbonate rock (white this time). Is this perhaps the boundary of the fault we were looking for?

For lunch, we went to the Alabama Hills, site of many a past Hollywood production, and clambored upon the rocks. Grace, carefully keeping her balance.

The rocks at the Alabama Hills are very tall: if you look carefully, you might make out a red blob in the center corresponding to Lisa's shirt. Or maybe not.

For our final geologic exercise of the day, we measured offsets (yippee!) along the site of the Lone Pine 1872 earthquake that leveled 26 of the 28 adobe houses then in Lone Pine (visible as the blob of trees to the right in the picture below).

To measure the offset, we found a stream with distinctive red rocks and measured their locations both upstream and downstream, which yielded an offset of 13 +/- 1 m on one side of the stream and 14 +/- 1 m on the other side.

Closeup of distinctive red rock (eg, front-center), with more ubiquitous white rock for reference (top left).

Alright, so you can't tell where the offset is in this picture... it was much more obvious in person. (The sun washed out all distinguishing features, and all the other students we'd used as markers has already walked back.)

The fault also produced a vertical offset of about 2-3 m.

And then the brave geology students packed into the bus and went home to rest for a few hours before classes began on Monday. The end.

Go to: Friday or Saturday

Return to my home page