Archive for the ‘other’ Category

Artifacts from the history of geology

27 February 2017

I had the good fortune last week to join a gathering of the Explorers’ Club at the great David Rumsey Map Center, a famous collection housed since 2016 in the Green Library at Stanford University. Laid out for our enjoyment were precious original maps from the 18th century West Coast exploring voyages of Vancouver, La Pérouse, Cook and more; maps from the 19th century Western surveys of Fremont, King, Powell and more; and two monuments of geologic mapping: William Smith’s 1815 map of England and Wales, and an edition of William Maclure’s 1809 map of the United States. I couldn’t resist a phone pic of that one.

macluremap

But you can examine the map online as closely as if you were holding a hand lens up to it, thanks to davidrumsey.com.

It’s hard to overstate how much effort it took to make this map, crude as it is. Geology was in a crude state at the time — Maclure distinguished only four classes of rocks, using the Neptunist scheme of Werner — and the territory of America could only be surveyed laboriously by foot, horseback, boat or coach. But this is how it began.

The 1815 Smith map, widely known as “the map that changed the world,” recently had a well-celebrated bicentennial, and strata-smith.com is where to get deeply into it. It was a rare privilege to take it in with my own eyes.

Another item that impressed me was a heavy lump of dark stuff encased in a silver box, engraved with the owner’s name in 1791. It was a genuine working lodestone.

lodestone1791

A lodestone is a naturally magnetized piece of the mineral magnetite. Not every piece of magnetite actually acts like a magnet, although of course a magnet will attract it strongly. It has to have a certain amount of impurities that, in effect, lock down its magnetization in a persistent state. It also appears to need its magnetization to be “set” by the strong field of a lightning bolt.

Lodestones were the first compasses. Mariners first learned to navigate with them around 1200. Later it was learned that you could magnetize ordinary iron by stroking it with a lodestone, although this was not permanent. Iron compass needles had to touched up periodically, and that was what this lodestone was for. A ship’s captain might keep one as a backup, but they’ve always been rare and expensive.

Not until the 1700s were truly permanent compass needles made using steel, and not until we mastered electricity did we no longer need lodestones. I have this magnetite specimen, about a thumbtip’s size, that acts as a magnet. I hesitate to call it a lodestone because nowadays you could make one by just zapping it.

lodestone

I was touched by these artifacts from a time when science was closely tied to artisanship, when everything was done by hand. Today, geologizing still benefits from the human hands and senses in ways that, say, physics and chemistry have long left behind.

The Rumsey Map Center is open to the public.

A march for science

6 February 2017

On Earth Day this year, April 22, an unknown but large number of scientists will be gathering together, in Washington and other cities, in a March for Science. I’ll be joining them somewhere in or near Oakland. Not only is science central to my being, it’s also central to our civilization.

As the March for Science site puts it, “At its core, science is a tool for seeking answers. It can and should influence policy and guide our long-term decision-making.”

While Earth Day lately has devolved into a day for innocuous tasks, this year it’s the best possible occasion for this march, because Earth science is the central science for the vital tasks ahead — breaking free of the destabilizing carbon economy, fostering a civilization that’s as sustainable as a forest, protecting and repairing the natural systems that provide our resources. Those tasks will require people who are experts at approaching the unknown, ninjas of curiosity.

curiousbarite

Curiosity is an undervalued skill. You won’t see it in job requirements. Yet without our intense curiosity, we would still be bands of hairless apes huddled in the African savanna, if not entirely extinct. And when new questions need answers, no one is better equipped to find them than scientists.

Consider what happened during the terrible Deepwater Horizon oil-well blowout in 2010. When standard procedures failed, a panel of scientists was called in to seek answers. When the Challenger spacecraft exploded in 1986, a panel of scientists was called in to seek answers.

These were not experts in drilling or spacefaring technologies; they were experts in handling the unknown. We support jobs for such people not just to keep them busy with their pet problems — what many call “pure research” or “curiosity-driven research” as a put-down — but to ensure a supply of curiosity ninjas. Everyone understands the need for top skills in the performing arts, athletics, law and war. It’s the same with science.

curiosity

I don’t know exactly what is driving so many powerful people to fear and downplay and deride and defund scientific research, but I know they need to be opposed and replaced by people who prize science. We have tremendous questions about our future on Earth. Who will seek their answers?

Museum-quality rocks from Oakland

30 January 2017

I keep saying that Oakland has geological features worthy of being put in textbooks. Today I’m here to show you that Oakland has rocks worthy of being in museums, and I’ve put them there.

In 2012, I was asked to put together a set of teaching rocks for the Chabot Space and Science Center. After all, other planets are made of rocks, right? It took some doing, but some of the rocks were easily available within Oakland’s borders in roadside exposures. The conglomerate of the Orinda Formation was one.

museumrocks-1

The red chert from the Franciscan Complex was another.

museumrocks-2

And of course there was our serpentinite.

museumrocks-3

All told, I made five sets of 15 rock types for the kids.

The next year I got a request from Las Positas College, in Livermore, for a boulder of blueschist. Turns out this little college teaches geology, because every citizen will benefit from a course, and students can get a head start on a 4-year degree there. I struggled one out of this streambed, where it wouldn’t be missed.

museumrocks-4

They installed it in their teaching garden as Rock J, on the left. It’s small compared to its mates, but that thing weighs a ton because high-grade blueschist is pretty dense.

museumrocks-5

My reward included a visit backstage to see their cool collections.

museumrocks-6

Then last year, I got a note out of the blue from the under-construction Maine Mineral and Gem Museum asking my help in building their collection. Maine is well known for its gemstone and mineral mines, but the state has no blueschist. I went to a quiet outcrop where it’s just lying around.

museumrocks-f

Got two nice boulders and couldn’t choose between them, so I sent them both. They told me one will go on display and the other will go in their teaching collection.

museumrocks-e

None of these are precious collectibles or gemstones. They’re just cool and educational.

I’ve pretty much stopped collecting rocks for myself because I’m not important enough. But museums are important enough.