Southern Alaska
The Yakutat block is a remnant piece of a smaller tectonic plate. This plate is thicker than the Pacific plate and isn't easily subducted beneath Alaska.
Instead, this block is colliding with southern Alaska causing uplift and mountain building in the Wrangell and Chugach-St. Elias mountain ranges and a rotation of southern Alaska, south of the Denali Fault.
Instead, this block is colliding with southern Alaska causing uplift and mountain building in the Wrangell and Chugach-St. Elias mountain ranges and a rotation of southern Alaska, south of the Denali Fault.
St. Elias Mountain, photo courtesy of AEC.