VOLUMES OF RECENTLY-ERUPTED RHYOLITE LAVA FLOWS IN THE YELLOWSTONE PLATEAU VOLCANIC FI ELD

The Yellowstone Plateau volcanic province consists of three calderas—YI, YII, and YIII. We calculated the volumes of post YIII rhyolite lava flows in ArcGis by averaging the height of each flow, estimating the pre-flow floor, and calculating the area of the flow. The total volume for the post 640 ka rhyolite flows is approximately 650 km³, which is over twice the volume of the Yellowstone II super eruption (280 km³). The post 640 ka rhyolite flows further divide into four periods from oldest to youngest as follows: 640 to 520 ka, 520 to 480 ka, 480 to 200 ka, and 200 to 70 ka. The fourth period comprises approximately 95% of post 640 ka magma volume. The flow rate of post 640 ka eruptions is consistent with the typical inter climactic flow rate (1 km³/ka); however, the flow rate of period four, subgroup two is 16 times higher (16 km³/ka). Geophysical and geochemical observations along with the volume of magma erupted since 640 ka suggest that Yellowstone will not have another super eruption.