The Wedgwood Rock; photo by Dennis Bratland via Wikimedia Commons (CC BY-SA 4.0)
Rock Out! Giant ‘wandering’ rocks deposited by glaciers are fascinating — and fun to climb on By Annie Fanning
Like an old-growth tree, a magnificent rock has a presence about it — a spirit, if you will. You don’t have to understand geology to commune with a great rock — or scramble up it and stand victorious on top — but knowing a little about the forces that created and shaped such rocks can turn a big boulder into a reallife natural history experience.
of ice on a continental scale, scraped and sculpted the terrain with cycles of freezing and flooding.
Wandering rocks When the glaciers advanced into the Puget Sound region 2 million years ago, the major features of our Northwest landscape — the volcanoes, mountain ranges, rivers and basins — already existed. The glaciers, colossal sheets
Rocks that have been transported by glaciers are called erratics because they have landed somewhere far from their natural homes.
As the ice advanced, sheering cliffs and cutting ravines, the glaciers picked up hunks of rock and carried them along. When the ice melted, these rocks were left miles away from their place of origin.
The term erratic is typically applied to large, irregularly shaped boulders that, FA M I LY A D V E N T U R E / 3 7
