Fossils capture natural history

July 25, 2006

By MARY AMES

Frontiersman

SUTTON - Once upon a long-time ago, it was warmer here.

You can see traces of plants that thrived then in the sedimentary rock layers in Sutton.

All you need is a truck with high clearance, and you can go to the end of the Jonesville Road. Some people come with picks and shovels, but you can find plant fossils there with no digging at all.

The wind-blown sands and silt that preserved the imprints of long-ago woody plants, filled the carbon content of the plant with minerals and compressed to make sedimentary rocks.

These babies are soft. They split apart and crumble easily. So you need to come with patience and a gentle touch more than with picks and poles.

I went to get my fair share of fossils on a holiday weekend, something I won't do again. Let the youth of America make their incessant beer runs to the store, careen over steep hills in daddy's pickup truck and make babies in the alder brush on the weekends.

Fossil hunting can be done during the week, I say.

&#8220I want to find a dinosaur bone,” said the man I fossiled with. He climbed about one-third of the way up a rock slide, sat down and picked up a rock.

Millennia ago, hominoids had to strike one rock against another to chip out tools. They had to do it to kill, skin and butcher food.

This present-day man struck one rock against another for about two hours, happy as a clam, looking for faint tracings in rocks from millennia ago.

How far we have evolved, I thought, that we do the same sort of thing, only now it's considered play instead of work.

I headed up the rock slide, picking and keeping, or picking and discarding as I went. Fossils of woody stems and leaves were everywhere within easy reach.

I got about half-way up the hill, when it dawned on me that flip-flops were not the best footwear for climbing rock slides.

How far we have evolved, I thought, and sat down myself.

Saber-toothed tigers, woolly mammoths and large sea creatures are preserved whole and in part north of the Alaska Range, where they stay preserved and chilled in the permafrost. Fossil ivory collectors claim territory on the Yukon River's high banks near Ruby, and many gold miners unearth ancient, frozen finds.

But in Sutton, between the Chugach and Talkeetna Ranges, plant fossils are the common thread that runs through the layers of sediments. Subjected to cycles of freezing and thawing, rain and wind, these deposits hold mostly plants. You always can hope for the rare fossil of a dragonfly, or the shank of dinosaur bone, and you may actually find one. But fossil hunting in Sutton is more about the little subtle things, the dark lines of a plant stem or the lacy imprint of a fern.

Sutton has everything a recipe for making fossils calls for, fine-grained sedimentary rocks that have been compressed over a long period, uplifted again toward the surface and exposed by quarries and road cuttings.

As exciting as they are, the down side of fossils is that they are finite. There are a limited number, and they are eroded easily or destroyed.

So, I only took my fair share, and I hope others do the same.

Contact Mary Ames at 352-2284 or mary.ames@frontiersman.com.