Deep Time

YOUR OROGENOUS ZONES DEPT./
JUNIOR YEAR ABROAD DEPT.

“Here’s to the Prof of Geology,
Master of all Natural History.
Rare boy he, and rare boys we,
to know such a great curiosity.” — Pat Boone toasting James Mason in song

Consider Old College, the place where the science of geology was founded, and where the concept of Deep Time — a bit older than the Bible’s 6,000 years — was promulgated, often against very stiff opposition indeed. Consider that Old College architect William Playfair was the nephew of the eminent geologist John Playfair, one of Edinburgh’s deepest Deep Time geology thinkers. Consider that, tasked with finishing the college according to eminent but defunct Robert Adam’s design, the eminent younger Playfair chose a facing of luscious mellow Leith sandstone, with columns cut in one piece from single beds. Consider my View of the Quadrangle in 1984; blackened with sulfur and soot, intruded by the parked fossil fuel burners that helped cause the corrosion. Then consider how many more cars we’ve added to the world since then [though, thankfully banished from the Quad.] Then read the HARROWING article below:

https://www.theatlantic.com/magazine/archive/2021/03/extreme-climate-change-history/617793/

Salisbury Craigs and Arthur’s Seat. Hiking where James Hutton hiked, learning to see it through his eyes, had a greater effect on me than I was able to understand back in that Deep Time. “Deep Time Geology” is built into the lore of the Edinburgh experience. Half the reason for the city’s intellectual eminence is due to the eminence of the craigs — the fact that these rocks sit a mere mile away from the crowded city, on public park land (actually Royal; thanks your Majesty). Queens, citizens, bums, rogues, foreign students and tourists alike can just clamber all over them whenever they like. And when they do, inevitably, they learn about Hutton’s and Playfair’s Deep Time.

James Hutton, 1776; by Henry Raeburn.
https://www.smithsonianmag.com/history/father-modern-geology-youve-never-heard-180960203/

“Hutton observed that basaltic rocks exposed in the Salisbury Craigs, just on the outskirts of Edinburgh, seemed to have baked adjacent enclosing sediments lying both below and above the basalt. This simple observation indicated that the basalt was emplaced within the sedimentary succession while it was still sufficiently hot to have altered the sedimentary material. Clearly, basalt could not form in this way as a precipitate from the primordial ocean as Werner had claimed. Furthermore, the observations at Edinburgh indicated that the basalt intruded the sediments from below—in short, it came from the Earth’s interior, a process in clear conflict with Neptunist theory.” — Britannica.
http://www.gutenberg.org/files/12861/12861-h/12861-h.htm

Hutton’s colleague and student, successor and champion John Playfair was no Pat Boone, but he did utter the most famous quote in geology in his 1803 eulogy of James Hutton, given before the Edinburgh Royal Society. Salisbury Craigs were impressive; but skeptics and students needed simple, unambiguous evidence of Deep Time. Playfair described his feelings on the bright day when Hutton took him and Sir James Hall in a boat around the rocky coast of Siccar Point, to point out two distinct layers of rock — only two — to see if they, too, could see them as Hutton saw them, in Deep Time:

John Playfair. Professor of natural philosophy at the University of Edinburgh, He wrote *Illustrations of the Huttonian Theory of the Earth* (1802), and *Outlines of Natural Philosophy* (1812–16).

“We felt ourselves necessarily carried back to the time when the schistus on which we stood was yet at the bottom of the sea, and when the sandstone before us was only beginning to be deposited, in the shape of sand or mud, from the waters of a superincumbent ocean. An epocha still more remote presented itself, when even the most ancient of these rocks, instead of standing upright in vertical beds, lay in horizontal planes at the bottom of the sea, and was not yet disturbed by that immeasurable force which has burst asunder the solid pavement of the globe….The mind seemed to grow giddy by looking so far into the abyss of time.”
— (Transactions of the Royal Society of Edinburgh, vol. V, pt. III, 1805)

It is worth pointing out, as an mnemonic device, and since nobody else ever has: the the name of Siccar Point, the smoking gun of Deep Time, comes from the Scots word siccar, which is cognate with Dutch zeker and German sicher, meaning “sure; certain; well-founded; bedrock.”

The Royal Park from the south, looking towards Sunshine on Leith.

The artist Clerk of Eldin was a friend of Hutton’s, and joined him to sketch his outcroppings as illustrations for the Theory of The Earth.

Hutton was the father of the rock cycle — the idea that, over aeons, mountains turn to jagged boulders which turn to rounded rocks which turns to smooth pebbles which turns either to sand (marine) or silt (riparian) which, in turn, turn back into rock, which gets compressed and sheared and intruded and metamorphosed and uplifted; and then eroded back down again. Playfair was the father of (what we would today call) the fractal geometry of watercourses and river systems and their role in that rock cycle.

Limerock Canyon, center; where its delta pays tribute to Little Tujunga Creek, which pays tribute to Big Tujunga, which pays tribute to the Mighty Los Angeles. The black dot and open circle mark the current channel, which has to be sluiced underneath the county road, which is at the lowest point in the whole syncline. The other channels to the north are now too high to carry the water. More later.

“Every river appears to consist of a main trunk, fed from a variety of branches, each running in a valley proportioned to its size, and all of them together forming a system of vallies, communicating with one another, and having such a nice adjustment of their declivities that none of them join the principal valley on too high or too low a level,—a circumstance which would he infinitely improbable if each of these vallies were not the work of the stream that flows in it.” — Playfair’s Law of Accordant Junctions; from Illustrations Of Huttontonian Theory

The reason I mention all this, is that I just found about a 15-foot section of washed-out wall in Limerock Canyon, where Deep Time, and the rock cycle, and the role of flow in the structure of the land, have been so astonishingly laid bare, that my “mind seemed to grow giddy by looking so far into the abyss of time.” In the next blog, I will try to explain and interpret why I think this muddy cutaway I found is so eminently fascinating.

Winter Gray, Summer Glad

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THE TRANSFORMATION OF LOPEZ CANYON

*“Californ-i-ay, where the rain doesn’t rain, it just drizzles champagne.”* — *Yip Harburg*

We finally had a real winter storm, two days of nice soft rain. Thank the Elye-wun, or whose-ever long white beards those are, flowing over the hills.

The hollyleaf cherries greeted me as if they were Irish Spring models, fresh and perky.

The deerweed has pinked up remarkably; the tired wilted look is gone everywhere. It’s a pioneer species in recovering disturbed areas: it cleverly fixes nitrogen in the soil, preparing for fertility.

The star of the show is an elegant hunting-pink buckwheat variety, Eriogonum fasciculatum, only this strain seems very gracile, and ripens to ruby red, not orange-brown.

The gracile buckwheat strain blooming white, and the deerweed in gold, in the June, 2020 Superbloom.

Comparing the LOC buckwheat, left, with your common-or-garden variety, right.

Re-capping from Feb. 2019:

January, 2019. Hills bare, contrasts extreme, and the creek bed was streaked with oak-char, but…potential!

Here’s one year later, Spring 2020:

In August 2020 we had a single-day spike of 118 degrees, and everything then alive, sizzled, I thought to death. By Christmas Day of 2020, after months of no rain, the hills had roasted up brown and crispy.

Christmas, 2020. Looks pretty fried, doesn’t it? But one month, and a couple inches of rain later:

January 29, 2021. The land is filling in with “Foothill Alluvial Fan Chaparral.” It’s far more diverse than ever.

Prodigies of Light Across The Transverse Ranges

Why Am I Constantly Surrounded by Transverse Ranges?

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YOUR OROGENOUS ZONES DEPT.

Look! Fault block mountains, there, and there…everywhere! All around! Closing in –!!

If Southern California is an Island on the Land, as Carey McWilliams dubbed it, the Transverse Ranges are the reason. They seal up the southern end of the Central Valley and separate Northern California from Southern California. The San Gabriels/Sierra Pelona division marks a key split in the northern and southern breeding populations among much of California’s wildlife. All that to do, and they’re still always on my back.

The mountains’ southerly-exposed bluffs and alluvial fans host the Foothill Alluvial Fan Chaparral and Southern Coastal Sage Scrub suites of the California Floristic Province, some of the youngest, rarest and most endangered organisms on earth.

Our microclimates are legion; this breeds diversity. Habitats feet apart, are completely different. Note the “Slope Effect” in Placerita Canyon on the back side (north side) of the San Gabriels:

Click below and fly souteasterly, over the whole Transverse Range Geomorphic in gorgeous relief:

But why do the mountain ranges trend easterly-westerly, when, as everyone knows, most of the other mountain ranges on the continent trend northerly-southerly? I asked a geologist. He didn’t get back to me, so I asked Norah and Ito. Here’s the scoop:

The cats say the reason is plate tectonics: subduction, rift zones, arc accretion, volcanics, uplift, rotation. Click on the animation by the seraphic C.R. Scotese. [Thank Thoth for his work at the Paleomap Project.] Try to spot western North America as it emerges: gasp when it does!

[Point of Awe: this is how far the plate theory has advanced since the 1970s, when the penny finally dropped for geologists and they realized it was the whole show, and had been, all along. Our generation of fifth graders were among the first kids who learned about “Gondwonaland” as basement bedrock of our knowledge. Our poor teachers must have been reeling with it, groping, grasping to understand so they could teach it to us. BLESS THEM.] But what I’ve been groping and grasping to understand lately, is that the Western Transverse Range Fault Block, Home Sweet Home, was formed all the way down by Baja. Santa Barbara and San Diego were suburbs of each other! Then it — we, the Transverse mountains and our Valley — were pushed and pulled and folded and rotated into position, transverse that is. This was quite recently indeed, and it’s still going on. It all hinges — quite literally — on the subduction of the “old Farallon Plate” and the rise of the East Pacific Rise, and the birth of the San Andreas Fault. Enjoy Tanya Atwater’s brief but brilliant video models of how it went down:

To really get an idea of this process at our very local level, consider Malibu Creek State Park. This is how it looks today:

Their resident geologist Don Kovalevsky has done a MAGNIFICENT set of illustrations tracking how this area of Santa Monica Mountains — and everything else — looked in various epochs. Click below for the whole series.

Click to access Don-Kowalewsky-MALIBU-CREEK-STATE-PARK-1.pdf

Today the Western Transverse Range Block is half covered by the ocean, with the Channel Islands the only peek-a-boo features. But the whole lump was made anyway from uplifted beach and marine sediments, bunched and folded, so even the bits that are high up in the mountains and miles from the tides, show their marine origin. I’m told you can find marine fossils, seaweed leaves and foot-wide nautilus shells, but I don’t need another solitary well-ventilated hobby…or do I?