A Sunday Night's "So What Is It?

After a busy weekend at the conference of the Far West Section of the National Association of Geoscience Teachers (an album of FB pictures here), Mrs. Geotripper and I headed up and out of Fresno, avoiding at all costs the flat confines of our Great Valley ("great" for a lot of reasons, but scenery is not necessarily among them). Our journey took us along a rather uncrowded mountain byway, and this one caused me to hit the brakes. It has now become our latest mystery photo...

So...tell us all what the heck this thing is, what it might be made of, and how it came to be. The first prize is the usual, a sense of smug satisfaction! Those are a couple of bedrock mortars at the base, providing some sense of scale (they are holes formed as the indigenous people of the region ground up acorns; they are 6-7 inches across). Below is a closeup of the base. The elevation is around 7,000 feet.

Extra credit will be given for the most original and outlandish explanation...

Reflections on an Accretionary Wedge: Why I am a Proud Member of the NAGT

I recently contributed to the latest Accretionary Wedge by talking about my first geology field trip, a 5 day backpack in the depths of the Grand Canyon way back in 1976. Part of the subsequent fallout was the unearthing of pictures of that trip, courtesy of Joy, who was one of my fellow travelers at the time (Facebook has some positive aspects, actually). I am a visually oriented learner, and my memories are most strongly reinforced by photographs, so this was a real pleasure to be able to relive part of my past with these grainy reminders (weren't Kodak Instamatics a wonderful form of photography?). For instance, I don't remember his name, but the bearded gentleman on the left was a very vocal vegetarian, but during the trip he seemed to get hungrier and hungrier, and when we reached the rim at the end of the five days, he looked at the menu in the Grand Canyon Lodge, and ordered a huge steak...

The professor who led that trip into the canyon was my inspiration to become a teacher of geology. That's him in the picture above, explaining to us how the basaltic sills were able to intrude the sediments of the Grand Canyon Supergroup, and how they helped us to place a date on the formation of those sediments. I still remember the shock of realizing that I really could almost literally travel through time by holding and understanding the origin of rocks that were hundreds of millions years old (imagine seeing the imprint of a raindrop that hit the ground 800 million years ago!). Looking at a picture of Marlin at work, I realize that I can trace many of the ideas I use in teaching to the things that he did all those years ago. Innovative ideas in teaching appear all the time, and they can be very effective, but I am reminded that the geological sciences are among the most historical of the academic disciplines as well. I mean this in the sense that there is an academic lineage that gives us a direct link to the founders of the science of geology, and that those brilliant and perceptive minds continue on with a different form of immortality (I wrote about this for a different Accretionary Wedge two years ago). I think what I am really saying is that people often become geologists and teachers not so much because they planned on it the way kids plan on being firefighters or police officers, but because they were inspired to pursue it because of the dedication of their teachers. I know I am over-generalizing about this, but I just don't see someone pursuing an MBA because he or she was inspired by a particularly good economics teacher, though I am willing to listen to counter-arguments! People have many different motivations for choosing their academic goals, after all.
I am thinking about this because I am preparing to drove down to Fresno to attend the fall meeting of the Far Western Section of the National Association of Geoscience Teachers at CSU Fresno (there is still room if you want to drop everything you are doing and drive on into the center of California and see some excellent Sierra Nevada and Coast Range geology- details are here). I joined NAGT nearly fifteen years ago, and have found in my involvement with the organization a sense of history and tradition of excellent teachers, and a myriad of innovative ideas and approaches to the teaching of the geological sciences. It has been a real privilege to work and share ideas with my colleagues from California, Nevada and Hawaii, as well as from all over the country. It's one thing to be inspired to follow an academic discipline because of the work of one or two excellent teachers, and quite another to travel with a large group of talented and innovative teachers who are collectively inspiring hundreds of students. And for that matter, because we encourage students to attend these meetings, it is great to see how they are laying the groundwork for the future of the earth sciences.

1976...that was 34 years ago. Wow. I still have that orange Alpenlite backpack with the innovative wrap-around aluminum frame (I actually worked in their factory for a few months all those years ago). I tried it on the other day, the way someone might try on the tux they wore to the high school prom. And just like the tux, the aluminum frame must have shrunk. Aluminum can shrink, right? I know I haven't changed and gotten...bigger. The frame obviously has shrunk!

The Other California: The Thicket of the Devil (Saturday's Mystery Photo Revealed)

Saturday's mystery photo was quickly identified by several readers, which didn't surprise me, given the uniqueness of the Transamerica Building of San Francisco. If I had put my other picture up instead, even more people would have identified the city in a split second:

You may have to click on the photo above to see it, but that's the Golden Gate Bridge and Marin Headlands in the far distance. Most of those who guessed where I was considered the hills above Oakland, which certainly makes sense, but JRepka came closest when he speculated that I might have been using a zoom lens while standing on Mount Diablo. That's exactly what I was doing.

Mt. Diablo holds a special place in California history. Anyone who owns property in the central part of the state quite likely owes the accurate locations of their land to the presence of the peak at a sort of structural nexus over the Sacramento Delta. The peak is relatively short, not even quite 4,000 feet, but its position allows one to see an incredible swath of real estate, from Lassen Peak to the north, to the vicinity of Sequoia National Park to the south, much of the Central Valley, and the Bay area from Loma Prieta Peak to St. Helena Peak. Soon after California became a state, Diablo was selected as the initial survey point for the grid pattern that established property lines in the state: the Township and Range System.

Without going into gory detail (that privilege belongs to the unfortunate students in my lab this week), the Township and Range system established consistent survey boundaries at a time when the federal government was using the prospect of free land to aid in the "settlement" of the western United States in the late 1800's and early 1900's (we shall disregard for the moment the fact that numerous Native Americans had lived on that land for centuries, and had to be "cleared" off of it to make room for "settlers"). By occupying and farming the land for five years, practically anyone could own their own piece of land.

The spectacular view from the summit led early on to claims that Mt. Diablo had the greatest "viewshed" in the world (viewshed: the total amount of land visible from the summit). This claim has been debunked, but the misconception persists. The fact doesn't detract from the stunning vista from the summit observation deck.

The name of the peak relates to a story from the early 1800's when some Native Americans (Chupcans) escaped Spanish control and hid in a willow thicket. The Spanish soldiers called the place the "Thicket of the Devil" (Monte del Diablo), but the name was later misinterpreted as Mount Diablo.

The peak and surrounding landscape is protected today as Mt. Diablo State Park, which encompasses some 20,000 acres (park brochure here). The park is nicely developed with picnic areas, group and individual campsites, and an extensive system of hiking trails. The park is very popular with Bay Area folks, but I suspect the mountain is little known outside of California. It is well worth a visit when you are in the region.

Lessee, the park's name, the survey stuff, the park facilities, the view, what am I forgetting? Oh, there's no description of the geology of the park. It's fascinating, but too extensive to cover tonight. Look for it in a coming post!

The Other California is my series on the lesser-known but geologically interesting corners of my beautiful state.

Fossil Discovery Center in Madera County is Opening!

Painting by David Douglas for the Fossil Discovery Center

If you live anywhere near the geographical center of California, there is some exciting paleontology news! Since the early 1990's Fairmead Landfill has been the source of thousands of specimens of a diverse Pleistocene fauna, including horses, camels, mammoths, sabertooth cats, giant ground sloths and many other fascinating inhabitants of the Central Valley thousands of years ago (I've posted several items about the excavations here and here). For years the San Joaquin Valley Paleontology Foundation has been planning to develop a center where students and visitors can learn about the intriguing history of our valley. And their plans are coming to fruition.

The San Joaquin Valley Paleontology Foundation is sponsoring the Grand Opening Celebration of the Fossil Discovery Center of Madera County. The journey began in 1993 with the discovery of a seven-foot mammoth tusk. Today their expedition into a pre-historic era continues, opening the past to students, scientists and community. Come and be a part of this historical event.

Wednesday, October 13, 2010

Ribbon Cutting -10:00 a.m.

Reception—5:30 p.m. to 7:30 p.m.

Fossil Discovery Center of Madera County
19450 Avenue 21 ½
Chowchilla, CA 93610
Take the Hwy 99 Exit 164, SW corner of Road 19 ½ & Avenue 21 ½

Refreshments will be served & tours provided.
--
San Joaquin Valley Paleontology Foundation
Board of Directors
sjvpaleo@gmail.com
http://www.maderamammoths.org/

Come and check it out!

The Other California: A Mystery Photo for a Saturday

I hope you are having a nice Saturday! Here's a photo mystery along the lines of the Silver Fox "Where in the West?" series (and no, I don't know where her picture was shot). What is in the photo, where was the photographer, what are some of the meteorological and geological circumstances? First prize is a feeling of accomplishment for guessing it first....

Columns on Columns: Pictures all over the Joint!

I was so pleased to see all the columns showing up in the geoblogosphere this week! Columnar-jointed columns that is. I added to the cacophony with shots from my field trip last week to Devils Postpile and the Owens Gorge east of the Sierra Nevada. The great collection of pictures that followed have been linked by Lockwood at Outside the Interzone. Check them out!

The meme reminded me of one of the greatest exposures of columns I've ever seen in my travels: they were along the east coast of the Isle of Skye in Scotland at Mealt Fall. Mealt Fall plunges over the sheer cliff and almost right into the sea. The cliffs are vertically jointed basalt flows that are related to the opening of the Atlantic Ocean in late Mesozoic and early Cenozoic time.

When I got on the plane for the Scotland trip in 2001, I had taken a grand total of 3 pictures on my very first digital camera. I barely knew what I was doing, and took only a handful of high resolution shots on one of the greatest trips of my life. I wish I could do the whole trip again, though, with the camera and experience I have now (and isn't just about all of life like that?).

Here are some of the columns lying on the beach below the cliffs.

I got a note from a geology student in Argentina, Ivan Ivanyvienen, who offered up an additional photo of columnar jointing in rhyolite at the San Juan Precordillera. It's a great shot and he has given permission to show it here on Geotripper. Thanks!

Important Geological Experiences: Accretionary Wedge #27

Lockwood should know better than to ask a bunch of geologists about their most important geological experiences. Talk about a way to get volumes written in record time! In fifty-plus years of life and 25 years of teaching, I've had a lot of experiences, and so many of them are treasured, but I suspect that many, if not most of us remember the moments when we decided to become geologists and/or teachers. I don't know how it is when one becomes a business or sociology major, whether there is a moment or a time when one becomes inspired to follow such a path, but I think a great many geologists can pick a moment. Mine was in 1976, and it happened deep in the Grand Canyon, and at a deep place in geologic time (and one of my first true insights to the vast expanse of it all).

I was a gawky, thin teenager in my first year at community college. I thought vaguely about a major that would allow me to work outdoors, as a ranger or something like that, and was leaning towards biology, but those classes were full, so I enrolled in an Earth Materials class that first quarter, followed by an Earth Processes class the second. My interest was piqued, but the possibilities didn't really come real to me until I also took a field studies course that second semester: Geology of the Grand Canyon. We met every Friday for two hours, and memorized the names of the layers at the canyon, reviewed the geologic history, visited the hall of tracks at the Raymond Alf Museum at Webb School in Claremont, and took a shake-down backpack in the southern California mountains. We took the shake-down because we weren't just visiting the Grand Canyon and looking over the edge. We were going in, spending 4 or 5 days below the rim, checking out each and every one of the layers from top to bottom (and back to the top again).

The trip involved a hike along some of the semi-maintained trails that are not usually a part of the tourist experience. The route down was along the New Hance Trail to the Colorado River, then along the Tonto Platform to Horseshoe Mesa, and then up the steep trail to Grandview Point. The entire journey was a revelation, as we saw the Paleozoic and Proterozoic sedimentary formations up close and personal (miles are meaningless in the canyon; when climbing out, you note what layer you've reached, not a mileage post), explored a copper mine, climbed through two limestone caverns (with ropes and helmets, no less), and even of all things, saw the aurora borealis from our camp on Horseshoe Mesa. I walked out of the canyon a geology major.

One of the singular moments that has stayed with me all these years was on the first day hiking into the canyon. We stood on a high ledge at the top of the Redwall Limestone and looked across at an outcrop of the Late Proterozoic Shinumo Quartzite. That's it, in the picture above. Our instructor, Marlin, asked us why the Shinumo seemed to stick up through the younger Tapeats Sandstone. There we were, a bunch of students without a clue, tired, and frankly I never would have even looked at the outcrop, but once directed, the rocks became an incredible landscape buried in the deep past.

The rocks of the Shinumo had once been an island, a 900-foot-high, miles-long island in the middle of a vast shallow sea that covered most of the western United States. It was so old that no plants or animals would have graced the slopes and cliffs. Just a few trilobites and worms squirming and burrowing about in the muds and sand in the water below. It was a stunning moment for me, to realize that we really could travel through time, reconstructing past worlds, and understanding the scope of change that has happened to the Earth's crust through deep time. For some reason, all the fossils, all the childhood knowledge, the book learning, none of it affected me as much as suddenly visualizing that ancient buried island.

We continued down the trail, and saw many more wonderful things, but nothing that so effectively awakened a curiousity about the Earth as that moment. It is one of my most vivid geological experiences. Thanks Marlin, for the insight.