"Till" the Next Time

Puget Sound has been covered with ice several times in the last million years, most recently about 20,000 years ago. These massive continental ice sheets where about 3,000 feet think over the Green and when they melted away they left behind all of the clay, sand, pebbles and boulders that were frozen in the ice. These poorly sorted sediments, like the one pictured below along the edge of the creek, are called glacial till.

(July 2022)

But the Green did not exist at that time. The creek would have cut down through the till and eroded the valley that exists today after the glaciers were long gone.