Cook Inlet Tidal Plain

Tidal plain along Anchorage's north shore.  Anchorage is near the northernmost tip of the Cook Inlet, which produces one of the largest tide ranges in the world because its long, narrow finger-like shape channels the tide into a surge traveling at 12 miles per hour having as much as a 40 foot range between low and high tide, if memory serves. This photo was taken near low tide, I think; that's a tree trunk washed up on the tidal plain.

Another factor contributing to the large tidal plain was the 1964 earthquake. Glacial silt composes much of the soil in and around Anchorage. The earthquake liquefied the fine, flour-like glacial silt, settling the ground as much as 8 feet and sending mudslides flowing into the inlet, extending the large, marshy tidal plains.

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