LIDAR survey of all of Isle Royale, with a nominal resolution of about 2 m is newly available for study. The data we show here came from Seth De Pasqual, at Isle Royale National Park. It reveals a striking topography which shows the dipping lava beds, and the prominent large lava flows, like the the region NE of Windigo. Differential erosion of lava flows occurs when soft material, like what is found in the amygdaloidal flow tops and along faults is preferentially removed and makes a topographic low, while the massive flow interiors resist erosion and become topographic highs. Glacial deposits mask the lava layers in part, especially southward in the image, where the flows are mostly covered, but protrude through glacial cover. The glacial materials are softer, but they also reveal wonderful geological information.
Drumlins are assymetrical glacial features which reveal the direction of glacial movement. The figure below shows an area near Lily Lake, which depicts conspicuous drumlins south of the lake. The pattern shows the direction of movement (from east to west) clearly, and the degree of elongation is also indicative of the rate of movement.
