The track of the Yellowstone hotspot: Volcanism, faulting, and uplift

Abstract

Southern Arm Belt I, Western Arm Belt III, Defined By Major late Pleistocene Faults Belt III, Southern Arm Belt III, Western Arm Belt IV, Defined by Major Tertiary Faults NEOTECTONIC DOMAINS EMANATING FROM THE YELLOWSTONE HOTSPOT The Present Cycle Belt IV and Older Cycles of Faulting Neotectonic Fault Belts and Historic Seismicity ALTITUDE AND THE HOTSPOT TRACK Possible Scales to Consider Yellowstone Crescent Of High Terrain Altitude Changes North of the Snake River Plain Rugged Mountains of Readily Erodible Rocks Pleistocene Glacier-Length Ratios and Altitude Changes Big Horn Basin Region Unidirectional Stream Migrations (Displacements) Convergent/Divergent Terraces Uplifted(?)Calcic Soils, Rock Creek Areas more than 250 km from the hotspot track Problems Relating Regional Uplift to the Yellowstone Hotspot DISCUSSION Alternative Models and their Problems Eastward Propagating Rift Crustal Flaws and the Origin of the SRP-YP Province Transform Boundary Zone Origin for the SRP A Meteorite Impact Origin for the SRP-YP Province A Two-Phase, Mantle Plume Model For the SRP-YP Region The Two Phase Model Evidence from Volcanism and Rifting Evidence from Faulting and Uplift Other Discussion Of Extensional Faulting Relation Between the Yellowstone Hotspot and Basin and Range Deformation CONCLUSIONS REFERENCES CITED Plate 1 caption Start of captions for figures 1-23 Start of tables (1, 2, and3) * Approved by the Director, 6/27/90.This report intended for publication by the Geological Society of America in a volume in honor of Steve Oriel.along the 1,100-km-long Nevada-Oregon rift zone, (3) the main phases of flood basalt volcanism of the Columbia River and Oregon plateaus, and (4) a change from calc-alkaline volcanism of intermediate to silicic composition to basaltic and bimodal rhyolite/basalt volcanism.Blackwell (1989) concluded that the volcanic track resulted from a mantle plume.Westaway (1989) argued that the V-shaped convergence of seismicity and faulting on Yellowstone could be explained by shearing interactions of an upwelling mantle plume and WSW motion of the North American plate.Malde (in press) advocates the hot spot origin of the eastern Snake River Plain, and contrasts this with the graben origin of the western Snake River Plain.