Up behind Dunsmuir House, near Oakland’s eastern end past the zoo and just before Sheffield Village, is a little wooded valley with this stream in it. It’s surely the reason that Dunsmuir House was built where it was, since the old places had to rely on surface water or their own wells. The Hayward fault runs very near this spot, through the swale that Dunsmuir House sits in. I don’t know where it leads. It may be an independent stream, between Arroyo Viejo and San Leandro Creek. It may connect with Elmhurst Creek, the ditch running past the south side of the Coliseum—that’s the way the contours seem to lead. Oakland has about twenty named streams, nearly all of them culverted today.
The bedrock is supposed to be either gabbro of the Coast Range Ophiolite or quartz keratophyre at the base of the Great Valley Sequence, but I wasn’t paying close attention to it. I remember it as nondescript, like a lot of Oakland bedrock.
I took this picture in March 2005.
Oakland Geology 
29 November 2007 at 4:18 pm
That’s called Lion Creek. A little branch of it drains an old sulfur mine at the end of McDonnell Avenue–our own acid mine drainage! I think the rocks there are the same stuff that’s in the old Leona Quarry, mapped as quartz keratophyre. Very hard, yellowish-gold colored rock that appears all over the city in stone walls and crushed stone. But I haven’t walked up the streambed yet.
There are so many places to visit. Today I walked up Broadway and onward all the way to Skyline, then down Broadway Terrace–a mammoth walk with about 1400 feet elevation gain.
28 November 2007 at 10:20 pm
check out the creek near leona lodge – maybe a couple canyons north of this one – it is also very cool – i’d be curious what rocks are there in that creek.