In ten minutes of walking through Ocotillo's Fossil Canyon, we found dozens of fossils and boulders of limestones, sandstones, marbles, schist, gneiss, quartz, phyllite, and gypsum.
  • In ten minutes of walking through Ocotillo's Fossil Canyon, we found dozens of fossils and boulders of limestones, sandstones, marbles, schist, gneiss, quartz, phyllite, and gypsum.
  • Image by Joe Klein
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Rocks are for climbing, collecting, throwing, building. They're also full of information, if you can read a rock. Scientists who become fluent in rock — geologists — peruse these old, hard texts and interpret them. Rocks chronicle what lived and when, how long things've been around, what it all looked like millions of years ago, what creation is made of, how we got to be where we are: rocks are magnificent writers. The rocks in and around San Diego have composed amazing, fiery stories for a very long time. An ancient ocean once covered this county; volcanoes used to spew here; and more or less sudden mountains rose and fell in San Diego more than once.

We stopped once along the 8, near Alpine, and Deméré bent down by the side of the road. "This is where our beaches come from."

This area is currently the most geologically active and diverse in the country. Our rocks are still writing away, every single day. Which makes these rocks of San Diego a good substratum for human writers as well. When specialists write or talk about rocks, they use weird words like gneiss, schist, plutonic, igneous, and zeolite. They could be carrying on about lizards or gods or cacti for all most of us know.

Tom Deméré: "I used to surf a lot. On bad surf days, I'd check out the terrific exposure on the sea cliffs."

Personally, I have trouble with the words that specialists use to refer to rocks; but since I'm writing an article about rocks, I'll have to work to keep the information tight and together. The earth, in essence, is one big rock. Talk about heavy subject matter. Our mother rock's so massive she's on fire in her center, molten from her own intense pressure. This is a potential that exists inside every rock.

Deméré wanted to show me "samples of some of the oldest rock in the county." It's called Julian Schist. Geologists estimate the stuff to be as much as 400 million years old. Along Route 78, up Banner Grade, at an elusive spot, Deméré found what he was looking for.

What I really need, to help in the translation of so much colossal material, and ultimately to pore back over the ancient natural history of San Diego County, is an honest-to-goodness, real-life geologist.

In San Diego, we've got lots of geologists. Most of the ones here work for the geology department at San Diego State University. The program at State's been around for over 70 years. Today, their laboratories boast cutting-edge facilities like ion chromatographs, mag separators, gravity tables, and jaw crushers. Their website shows composites, bios, and e-mail contacts for over 25 highly trained, advanced-degree-holding geologists. Surely, if anyone ever required rock-related aid, then San Diego State'd be the locale to go to.

I want to mention, as an aside, from the pictures on the SDSU website, that geologists don't particularly look like geologists. Not that I can tell you exactly what I think a geologist is supposed to look like. It's just that geologists don't seem to share a single discernible physical "type." That is, each one of them looks more or less completely different. I don't know why this would surprise me — the fact that geologists can be jolly and dour, young and old, men and women, long-haired and short-, from here and from elsewhere — except that I thought a life with rocks would, I don't know, kind of turn a person into stone a little, maybe harden an individual's demeanor, the way old married couples finally tend to look alike. Geologists do share some similarities, of course. For one thing, they appear reluctant to respond to mass e-mails from the media. Within the body of the personal-ad-like e-letter I sent them and sent them and sent them, I wrote that I would need "access to an articulate and engaging geologist, for interviews and a long drive or two on a network of roads." Then I went on to indicate that I would want the geologist "to comment on what he or she sees as we drive and to stop me when we see something interesting, to get out of the car, hammer on rocks, describe them, and explain exactly what these rocks tell us re SD paleohistory."

I received exactly two responses. One geologist sent back word that he was "looking into it." And the other provided me with a nomination. David Kimbrough e-mailed back that I should be talking to the folks at the San Diego Natural History Museum. "Tom Deméré is the person to start with," Kimbrough wrote to me. And so I sent a copy of my eager mass electronic mailing to this man at the museum, this recommended geologist.

Tom Deméré, Ph.D., replied immediately. Only he didn't just e-mail, he called me. And his reaction was enthusiastic. When we talked about a driving trip, he said, "It sounds exciting."

Exciting? Why not, I thought. Our San Diego County landscape has made me want to pull over and break into spontaneous applause now and again. And if this Deméré fellow could find it "exciting" to drive and look at rocks all over creation for the better part of a hot April day, then he was definitely my Rock Man.

Our region has a natural history that extends back millions of years and encompasses many past physical "stages" and biological "players." Even the slightest glimpse into this dynamic past leaves me with a profound sense of wonder. That's a quote from Deméré, the quote he chose for his page that links to the San Diego State University Geology Department's website. The university lists Deméré as an adjunct professor, which means that SDSU doesn't pay him but it does extend to him unlimited lifetime access to its facilities, collections, and libraries.

As curator of paleontology, Dr. Deméré has occupied the Joshua L. Bailey Jr. Chair of Paleontology at the Museum since 1994. (Now I'm reading from the San Diego Natural History Museum's website.) Before that he served as collection manager in the department. Tom's research focuses on the evolutionary history and paleobiology of pinnipeds and cetaceans. ("Pinniped" and "cetacean" are the scientific words for seal and sea lion, porpoise and whale.) [Deméré] is also keenly interested in the geology and paleontology of southern California and Baja California and has published numerous scientific and popular articles on these subjects.

Deméré's credentials were impeccable, and he was into the idea, so we scheduled a real-life rock-reading field trip. We would meet at 8:00 a.m. in Balboa Park, in the parking lot of the museum, and then head out to study the roadside rocks of San Diego County.

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