In stark contrast to the mountainous Pacific Northwest of today, during the Eocene epoch (~ 55 ~ 34 Million YearsAgo (MYA) it was quite flat. However just as today, the region then was lush with vegetation and interlaced with braided streams meandering from what is now Eastern Washington on to the Pacific Ocean. This was a tropical swamp with exotic plants and animals (although some would be familiar yet today). As the streams approached the ocean, they slowed and their sediments of sand, clay, and silt carried from huge rock formations to the east, settled out. Over millions of years these sediments accumulated, were compressed by gravity and tectonic forces, and solidified into immense geologic rock formations. This bucket is about one of these structures - the Chuckanut Formation made up primarily of sandstone, siltstone, conglomerate, and shale, with pockets of coal from the ancient compressed vegetation.
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