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Spring 2011 ES407 Senior Seminar New Approaches to Geomorphic Analysis of Cinder Cones at Newberry Volcano. Jody “Coyote” Becker, Kelsii “Crusher” Dana, Dan “Ger” Dziekan, Ricky “Flicky” Fletcher, Bill “W.” Vreeland, Steve “Dr.” Taylor. Introduction (Taylor) Physiographic Setting (Fletcher)
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Spring 2011 ES407 Senior Seminar New Approaches to Geomorphic Analysis of Cinder Cones at Newberry Volcano Jody “Coyote” Becker, Kelsii “Crusher” Dana, Dan “Ger” Dziekan, Ricky “Flicky” Fletcher, Bill “W.” Vreeland, Steve “Dr.” Taylor
Introduction (Taylor) • Physiographic Setting (Fletcher) • Tectonic Setting (Vreeland & Dziekan) • Geologic History (Becker & Dana) • The “Cinder Cone Problem” / Previous Work (Taylor) • Cinder Cone Methodology • Cone Age-Morphology Concept (Fletcher & Dziekan) • Structural Cone Emplacement (Becker) • Cinder Cone Alignment (Vreeland) • Lidar-Based Elevation Models (Dana) • New Research / Pilot Testing with LIDAR Data • Cinder Cone Drainage Density vs. Age (Becker) • Modified Two-Point Analysis (Vreeland) • Newberry Glacial Hypothesis (Fletcher) • Lava Flow Margin Mapping with Lidar (Dana) • Summary and Future Research (Taylor)
INTRODUCTION Steve Taylor
Cascade Volcanic Arc Linear chain of volcanoes extending from southern British Columbia through Washington and Oregon into northern California WOU Bend • Newberry Volcano • 56 km east of Cascade Crest • 40 km south of Bend, Oregon
History of Newberry Work at Western Oregon University 2000-Present WOU Class Field Trips and Contextual Learning Modules 2000 Friends of the Pleistocene Field Trip to Newberry Volcano 2002-2003 GIS Compilation and Digitization of Newberry Geologic Map (after MacLeod and others, 1995) 2003 Giles and others, Digital Geologic Map (GSA Fall Meeting) 2003 Taylor and others, Cinder Cone Volume and Morphometric Analysis I (GSA Fall Meeting) 2005 Taylor and others, Spatial Analysis of Cinder Cone Distribution II (GSA Fall Meeting) 2007 Taylor and others, Synthesis of Cinder Cone Morphometric and Spatial Analyses (GSA Cordilleran Section Meeting) 2001-Present Templeton, Petrology and Volcanology of Pleistocene Ash- flow Tuffs (GSA Cordilleran Section Meeting 2004; Oregon Academy of Science, 2007; Am. Geophys. Union, 2010) 2010-2011 Newberry LIDAR Elevation Data Available; ES407 Senior Seminar Pilot Tests Next Generation Research Strategies on Cinder Cones; Updated Literature Review
Caldera Summit Newberry Volcano, South View from Lava Butte Lookout Basaltic Aa Lava Flow fromLava Butte; ~7000 yrs BP
Newberry Volcano, View to S-SE from Paulina Peak Lookout High Lava Plains Fort Rock (Tuff Ring) Basin and Range Newberry Cinder Cones
Newberry Volcano, View to West towards High Cascades from Paulina Peak Lookout South Sister Broken Top Middle Sister
Newberry Volcano, View into Summit Caldera from Paulina Peak Paulina Lake East Lake
Arc Volcanoes related to Cascadia Subduction Zone Juan de Fuca plate thrust beneath North American plate
Eastward Arc Migration Magma Source in Subduction Zone Back Arc Fore Arc 7 – 0 Ma 35 – 7 Ma High Cascades Newberry Position Western Cascades Decreasing Slab Dip
Current Crustal Deformation Rates and Directions Brothers Fault Zone Newberry Basin and Range Stretching Meigs et al., 2009
Overview of Newberry Volcano • Shield-shaped composite volcano • N-S orientation, 64 km x 40 km • Total Area > 1300 km2 • Summit Caldera Area = 44 km2 • Elevation: 1300 m – 2400 m; Relief ~1100 m • Composition: Basalt to Rhyolite • Estimated Volume = 460 km3 • >400 cinder cones and fissure vents • Quaternary in Age • Less than ~500,000 yrs old • Holocene activity: 10,000 – 1200 yrs BP • One of largest U.S. Quaternary volcanoes • Historic Annual Precipitation: 30 in/yr • East flank rain shadow of Cascades
Regional Geology • Cenozoic volcanism: • Ignimbrite sweep • Flood basalts • Bimodal (modern) • High Lava Plains • Snake River Plain Oregon-Idaho: • Paleozoic-Mesozoic oceanic volcanic arcs • Accretionary complexes • Basinal successions
Regional Volcanism Two migrating tracks: • NE along Snake River Plain toward Yellowstone • WNW along High Lava Plains (Newberry) Indicated link between High Lava Plains and Cascades volcanism: • Increased output • Isotopic similarities • Merging structures
Geology after Walker and MacLeod (1991); Isochrons in 1 m.y. increments (after MacLeod and others, 1976)
Central Pumice Cone 7200 yrs BP Big Obsidian Flow 1250 yrs BP East Lake
STATEMENT OF THE PROBLEMSteve Taylor GEOMORPHIC ANALYSIS OF CINDER CONES
Cinder Cone Research Questions Are there morphologic groupings of ~400 cinder cones at Newberry? Can they be quantitatively documented? Are morphologic groupings associated with age and state of erosional degradation? Are there spatial patterns associated with the frequency, occurrence, and volume of cinder cones? Are there spatial alignment patterns? Can they be statistically documented? Do regional stress fields and fault mechanics control the emplacement of cinder cones at Newberry volcano?
Lava Butte Cone and Aa Flow ~7000 yrs BP (post-Mazama) Ash & Pumice
Existing Methodology • Digital Geologic Map Compilation / GIS of Newberry Volcano (after McLeod and others, 1995) • GIS analysis of USGS 10-m DEMs • Phase 1 Single Cones/Vents (n = 182) • Phase 2 Composite Cones/Vents (n = 165) • Morphometric analyses • Cone Relief, Slope, Height/Width Ratio • Morphometric Classification • Volumetric Analyses • Cone Volume Modeling • Volume Distribution Analysis • Cone Alignment Analysis • Two-point Line Azimuth Distribution • Comparative Monte Carlo Modeling (Random vs. Actual)