Chapter 1: The track of the Yellowstone hot spot: Volcanism, faulting, and uplift 论文

摘要

The track of the Yellowstone hot spot is represented by a systematic northeast-trending linear belt of silicic, caldera-forming volcanism that arrived at Yellowstone 2 Ma, was near American Falls, Idaho about 10 Ma, and started about 16 Ma near the Nevada-Oregon-Idaho border. From 16 to 10 Ma, particularly 16 to 14 Ma, volcanism was widely dispersed around the inferred hot-spot track in a region that now forms a moderately high volcanic plateau. From 10 to 2 Ma, silicic volcanism migrated N54°E toward Yellowstone at about 3 cm/year, leaving in its wake the topographic and structural depression of the eastern Snake River Plain (SRP). This <10-Ma hot-spot track has the same rate and direction as that predicted by motion of the North American plate over a thermal plume fixed in the mantle. The eastern SRP is a linear, mountain-bounded, 90-km-wide trench almost entirely(?) floored by calderas that are thinly covered by basalt flows. The current hot-spot position at Yellowstone is spatially related to active faulting and uplift.