THE YELLOWSTONE CALDERA VOLCANIC CALDERA SUPERVOLCANO YELLOWSTONE NATIONAL PARK THE UNITED STATES SOMETIMES THE PARK THE NORTHWEST CORNER WYOMING THE MAJOR FEATURES MEASURE THE LAST THE PAST HUCKLEBERRY RIDGE ERUPTION MILLION YEARS AGO THE ISLAND HUCKLEBERRY RIDGE TUFF MESA FALLS THE HENRYS FORK MESA FALLS TUFF LAVA CREEK YEARS AGO LAVA CREEK TUFF VOLCANISM YELLOWSTONE RECENT ERUPTIONS CALDERAS LIE HOTSPOT ROCK THE MANTLE RISES TOWARD THE SURFACE PLATEAU PREVIOUSLY HELPED CREATE EASTERN SNAKE RIVER PLAIN THE WEST HUGE VOLCANIC ERUPTION THE HOTSPOT APPEARS MOVE TERRAIN IN FACT DEEPER REMAINS THE NORTH AMERICAN PLATE MOVES MILLION YEARS SUCCESSION VIOLENT LESS FLOODS BASALTIC LAVA EASTERN THE SNAKE RIVER PLAIN DOZEN MASSIVE CLASSIFIED VOLCANIC ERUPTIONS EMPTY STORES MAGMA CAUSE OVERLYING COLLAPSE MAGMA CHAMBER FORMING GEOGRAPHIC DEPRESSION IDENTIFIED STRADDLES THE BORDER MCDERMITT VOLCANICLASTIC FAULTS DEFINE DIAMETER CARMACKS GROUP YUKON CANADA INTERPRETED YOUNGER VOLCANIC FIELD NEVADA OREGON BORDER TERMINATE SOUTHERN IDAHO THE EVENT DEPTH ONE FOOT AWAY NORTHEASTERN NEBRASKA HERDS RHINOCEROS OTHER ANIMALS ASHFALL FOSSIL BEDS STATE HISTORICAL THE UNITED STATES GEOLOGICAL SURVEY USGS ESTIMATES MAJOR EXTRUDING STEAM DEFINED TERM USED TO DESCRIBE VOLCANIC FIELDS PRODUCE THUS THE LATEST SMALLER WEST THUMB LAKE SUPER LARGEST TIMES THE MOUNT THE NEXT THE ONLY VISIBLE EXPLOSIVE ERUPTIONS LAVA FLOW THUMB LAKE YELLOWSTONE EXPLOSIONS EXPLOSION LEFT CRATER ON THE EDGE OF YELLOWSTONE LAKE THE CENTER VOLCANIC ACTIVITY GEOTHERMAL VENTS SCATTERED FAMOUS OLD FAITHFUL GEYSER PLUS GROUND SWELLING ONGOING INFLATION UNDERLYING GREAT COVE BELOW COVE GASES KEPT DISSOLVED PRESSURE THE PRESSURE SUFFICIENT DEGREE GEOLOGICAL BUBBLE RUNAWAY EXPANSION RESULTS RELIEF CRUST MATERIAL GAS EXPLOSION ANALYSIS EARTHQUAKE DATA UNDERGROUND SCIENTISTS BELIEVE PROPORTION MELT THE CHAMBER VOLCANIC TECTONIC NATURE MEASURABLE EARTHQUAKES MEASURING MAGNITUDE DETECTED SHORT PERIOD EVENT EARTHQUAKE SWARM MEASURED CAUSED SLIPS RATHER MOVEMENTS QUAKES SWARM HAITI CHILE EVER REACHED THE BACKGROUND DUST VOLCANIC ASH GEOLOGISTS MONITORING RISE AND FALL OF AVERAGE INDICATION CHANGES UPWARD FLOOR ALMOST THREE TIMES GREATER THAN MEASUREMENTS THE LAND SURFACE THE WHITE THE END UPLIFT UNIVERSITY OF UTAH NATIONAL PARK SERVICE VOLCANO OBSERVATORY EVIDENCE EVENTS NEITHER REGULAR CONCLUSION THE AFTERMATH PUBLICATION STUDY FINDING SIZE BODY BENEATH STATEMENT WEBSITE FINDINGS DO NOT GEOLOGIC HAZARDS CERTAINLY INCREASE THE CHANCES THE NEAR FUTURE CONTRARY MEDIA OVERDUE REPORTS PUBLISHED GSA TODAY FAULT ZONES FUTURE AREAS LAVA FLOWS AGED THE THIRD AREA FOCUS GREATER HAZARD COMES HYDROTHERMAL ACTIVITY TURBID LAKE INDIAN POND RESEARCHERS DISPLACED MORE THAN US WATER COLOSSAL WAVES CAPPED SYSTEM HYDROTHERMAL EXPLOSION RESEARCH SHOWS REACH LANDERS EARTHQUAKE MOJAVE DESERT TRIGGERED DENALI FAULT ALASKA ALTERED ACTIVITY HOT SPRINGS MONTHS AFTERWARD THE SOURCE GEOSCIENTISTS HYPOTHESIZE THE EFFECT INTERACTION LOCAL CONDITIONS THE LITHOSPHERE UPPER MANTLE CONVECTION DEEP MANTLE ORIGIN MANTLE PLUME CONTROVERSY SUDDEN APPEARANCE GEOLOGIC RECORD COLUMBIA BASALT FLOWS CAUSING SPECULATION ICELAND HOTSPOT ICELAND PLUME LONG VALLEY CALDERA VALLES CALDERA LA GARITA CALDERA CLOSE RELATED BBC NATIONAL