Saturday, May 10, 2008

A Walk with Geologists

Some days even during the busy seasons, the farm is quiet, but now that it is summer we will get folks knocking at the back door with unusual requests. I was, thus, intrigued but not surprised when my husband announced that some geologists had asked to walk through our farm down to the beach to look at the rocks. We met them later in the Pentland Hotel and learned more about their interest in the rocks. They are staff geologists currently looking at rocks like ours in Shetland. Two big differences between our rocks and those in Shetland: their rocks may have oil and their rocks are under about 2 kilometers of sea and other rocks. So our rocks, like so much of Scotland, are beautiful and accessible but not easily converted into an income.

I confessed to having nearly failed freshman geology back in Bloomington, Indiana where everything is limestone anyway. I added, however, that I had recently picked up in the library a biography of the man responsible for making geology a science in the United Kingdom (The Map that Changed the World: The Tale of William Smith and the Birth of a Science, Simon Westchester). Apparently that was enough to tip the scales in my favor, and the geologists were kind enough to invite us to tag along.

The first revelation of the day was that what I had formerly thought of as a sandy beach was in reality an aeolian sand bed. I stepped a bit more lightly on the venerable grains now having been properly introduced.

The cliff face, which I could recognize at least as sedimentary rock (We all remember the three classifications: sedimentary, metamorhpic and igneous, right? from those little cigar-box collections of rocks around the world or was I more of rock-geek than average?) From the geologists I was able to learn the cliff face was more specifically, Devonian sandstone. "Devonian" means it measures its tenure in the hundreds of millions of years. The stripes are the result of drying and refilling a freshwater lake over millions and millions of years.
After having met the Devonian sandstone and had my chronometer set back to register in millions of years, I was introduced to this unassuming red rock. The colour and texture seemed to stand out from others on the beach, so I asked one of the geologists. He explained that it is a conglomerate. Underneath the mottled layers laid down on top is granite. This small boulder is the grandfather of the Devonian sandstone. It is about 2 billion years old. My chronometer simply could not register to that scale. I dubbed him Grandfather Rock although I doubt that this title makes much difference to him.

I also learned a bit about the controversies around sineresis--the cracks and the filling in some of the rocks that give them a wrinkled surface. As an amateur, I can admire them without worrying about the niceties of process. I tucked a particularly beautiful example of a flat wrinkled rock under my arm --my pockets were already full of the tide-bounced, wave jumbled rocks that are so perfectly rounded that they demand to be picked up.

As the geologists gathered to study fractures in terms that my lay brain could not follow, I wandered among the rocks simply admiring them. I came across this beauty and dubbed her Grandmother Rock. I think she is considerably younger than Grandfather, but what is a few million years to a rock?

Reading William Smith's biography reminded me of the critical role that geology in particular played in overthrowing the idea that the creation of the earth and everything in it was a matter of faith only and that even to inquire into such things as the ages of rocks was heresy.

Simon Winchester recalled for me the personal attacks that those who chose to explore the world and to hypothesize about their place in it had had to endure. William Smith suffered not only the attacks against his science but also the fact that he was a self-educated amateur. He challenged both class and faith.

Having sauntered along the brae and on the beach with the geologists I shared the conviction that the more we know about something the more likely we are to be awed by it. I have always struggled to understand the idea that using our God given intellect could ever be construed as heresy. Having grown up in Indiana which is known for its conservatism and "Bible-belt" dogmatisim, I have friends who have a very different perspective. I have learned to keep the friendship by steering clear of that conundrum. I personally find it a gift to know that Grandfather Rock, sitting peacefully on his aeolian sand bed, has been around for 2 billion years and counting. For me such gifts are not just intellectual treats. They are a reminder of just how magnificent a world it is over which we have been given stewardship.

I walked down to the beach a few days after this visit. The tides had altered the rocks on the beach. I was able to see Grandfather Rock although not easily able to get there again--a line of heavy sea weed made walking too treacherous. There was no sign of Grandmother Rock. She may be back underwater or rolled further up on the shore and hidden among the cliff edge. Time operates on the aeolian sand bed in both macro and micro scale. Grandmother Rock may be back again but in her own time.

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At 11:40 PM, Blogger TerriRainer said...

You know more about rocks than I do! Sounds like you had a good time just enjoying nature though.

:) Terri

At 5:21 PM, Blogger landgirl said...

I know more about rocks than I did before but " alot" would be too grand a statement. I perused The Highland Geology Trail to prepare for the walk.


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