¿Jeremiah?

The Sound has been reshaped by the scouring action and till deposition of the Wisconsin Glaciation, which extended in this region as far south as Olympia; the soils of the region, less than ten thousand years old, are still characterized as immature. During glacial maximum a large meltwater lake formed at the icewall's forefront, drained by the Chehalis River; its sediments form the blue-gray clay identified as the Lawton Clay. As icebergs calved off the toe of the glacier, their embedded gravels and boulders were deposited in the chaotic mix of unsorted till geologists call glaciomarine drift. Many beaches about the Sound display glacial erratics, rendered more prominent than those in coastal woodland solely by their exposed position; submerged glacial erratics sometimes provide hazards to navigation. The sheer weight of glacial-age ice depressed the landforms, which experienced isostatic rebound after the ice sheets had retreated; because the rate of rebound was not synchronous with the post-ice age rise in sea levels, the bed of what is Puget Sound, filled alternately with fresh and with sea water. The upper level of the lake-sediment Lawton Clay now lies about 120 feet (37 m) above sea level.