Filters: Tags: caldera (X) > Types: ArcGIS Service Definition (X)

Filters Date Range Past year (0) Past month (0) Past week (0) Past day (0) Custom range... To   Search Extensions ArcGIS Service Definition (2) ArcGIS REST Service (1) Types ArcGIS REST Map Service (2) Downloadable (2) Map Service (2) Contacts Joel E Robinson Volcano Science Center U.S. Geological Survey - ScienceBase Joel E Robinson Natural Hazards More... Categories Data (2) Tag Types Theme (2) Place (2) USGS Scientific Topic Keyword (2) Harvest Set (2) Tag Schemes Common geographic areas (2) Lithologic classification of geologic map units (1) USGS Thesaurus (2) Alexandria Digital Library Feature Type Thesaurus (2) Marine Realms Information Bank (MRIB) keywords (1) None (1) none (1) More... View Results as: JSON ATOM CSV

Database for the Geologic Map of the Bonanza Caldera Area, Northeastern San Juan Mountains, Colorado The San Juan Mountains in southwestern Colorado have long been recognized as a site of exceptionally voluminous mid-Tertiary volcanism, including at least 24 major ignimbrite sheets (each 150-5,000 km3) and associated caldera structures active at 33-23 Ma. More recent volcanologic and petrologic studies in the San Juan region have focused mainly on several ignimbrite-caldera systems: the southeastern area (Platoro complex), western calderas (Uncompahgre-Silverton-Lake City), the central cluster (La Garita-Creede calderas). The northeast San Juan region that was far less studied until recently occupies a transition between earlier volcanism in central Colorado and the larger-volume younger ignimbrite-caldera foci... Categories: Data; Types: ArcGIS REST Map Service, ArcGIS Service Definition, Downloadable, Map Service; Tags: Bonanza, Colorado, North America, Saguache, USGS Science Data Catalog (SDC), All tags... United States, Volcanology, caldera, explosive eruptions, geology, geology, volcanoes, Fewer tags Database for the geologic map of the central San Juan caldera cluster, southwestern Colorado This geodatabase contains all the geologic map information for the Geologic Map of the San Juan caldera cluster, southwestern Colorado and is part of U.S. Geological Survey Geologic Investigations Map Series I-2799. The San Juan Mountains are the largest erosional remnant of a composite volcanic field that covered much of the southern Rocky Mountains in middle Tertiary time. The San Juan field consists mainly of intermediate-composition lavas and breccias, erupted about 35-30 Ma from scattered central volcanoes (Conejos Formation) and overlain by voluminous ash-flow sheets erupted from caldera sources. In the central San Juan Mountains, eruption of at least 8,800 km3 of dacitic-rhyolitic magma as nine major ash... Categories: Data; Types: ArcGIS REST Map Service, ArcGIS Service Definition, Downloadable, Map Service; Tags: Andesite, Ash-flow tuff, Basalt, Central San Juan Caldera Cluster, Central San Juan Mountains, All tags... Colorado, Geochemistry, Gunnison, Lava flow, Pyroclastic rock, Rhyolite, San Juan, Tuff, USGS Science Data Catalog (SDC), United States, Volcanic breccia, Volcanology, Welded tuff, caldera, faulting (geologic), faulting (geologic), geoscientificInformation, volcanic activity, volcanic activity, volcanic eruptions, volcanic features, volcanic rocks, volcanic rocks, volcanology, volcanology, Fewer tags