Ice Age Natural History

Geological historians agree that a series of Ice Age floods, bursting down from the Montana and Canadian border, over 15,000 years ago, define Tualatin’s geography and left lasting clues about prehistoric life here. The cataclysmic Ice Age Missoula Floods carried with them rich silt, resulting in the area’s fertile farmlands, as well as many huge boulders known as “glacial erratics.” (A glacial erratic is a piece of rock that differs from the size and type of rock native to the area in which it rests.) Among the glacial erratic that were tossed along with the pre-historic rushing waters include a 20,000 lb. granite boulder and 5,500 lb quartz rock, both unearthed from local farms in recent years, and now displayed in front of the Tualatin Historical Society. With other geological artifacts and information, they tell the story of the Tualatin landscape.