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

Newberry Volcano 56 km east of Cascade Crest 40 km south of Bend, Oregon Cascade Volcanic Arc Linear chain of volcanoes extending from southern British Columbia through Washington and Oregon into northern California Bend WOU

History of Newberry Work at Western Oregon University 2000-Present WOU Class Field Trips and Contextual Learning Modules 2000Friends of the Pleistocene Field Trip to Newberry Volcano GIS Compilation and Digitization of Newberry Geologic Map (after MacLeod and others, 1995) 2003Giles and others, Digital Geologic Map (GSA Fall Meeting) 2003Taylor and others, Cinder Cone Volume and Morphometric Analysis I (GSA Fall Meeting) 2005Taylor and others, Spatial Analysis of Cinder Cone Distribution II (GSA Fall Meeting) 2007Taylor and others, Synthesis of Cinder Cone Morphometric and Spatial Analyses (GSA Cordilleran Section Meeting) 2001-PresentTempleton, Petrology and Volcanology of Pleistocene Ash- flow Tuffs (GSA Cordilleran Section Meeting 2004; Oregon Academy of Science, 2007; Am. Geophys. Union, 2010) Newberry LIDAR Elevation Data Available; ES407 Senior Seminar Pilot Tests Next Generation Research Strategies on Cinder Cones; Updated Literature Review

PHYSIOGRAPHIC SETTING Rick Fletcher

Caldera Summit Newberry Volcano, South View from Lava Butte Lookout Basaltic Aa Lava Flow from Lava Butte; ~7000 yrs BP

Newberry Volcano, View to S-SE from Paulina Peak Lookout Basin and Range Fort Rock (Tuff Ring) Newberry Cinder Cones High Lava Plains

Newberry Volcano, View to West towards High Cascades from Paulina Peak Lookout South Sister Middle Sister Broken Top

Newberry Volcano, View into Summit Caldera from Paulina Peak Paulina Lake East Lake

TECTONIC SETTING Dan Dziekan and Bill Vreeland

Arc Volcanoes related to Cascadia Subduction Zone Juan de Fuca plate thrust beneath North American plate

Magma Source in Subduction Zone Fore Arc Back Arc Newberry Position Western Cascades High Cascades 35 – 7 Ma 7 – 0 Ma Eastward Arc Migration Decreasing Slab Dip

Meigs et al., 2009 Current Crustal Deformation Rates and Directions Basin and Range Stretching Brothers Fault Zone Newberry

GEOLOGIC HISTORY Jody Becker and Kelsii Dana

Overview of Newberry Volcano Shield-shaped composite volcano N-S orientation, 64 km x 40 km Total Area > 1300 km 2 Summit Caldera Area = 44 km 2 Elevation: 1300 m – 2400 m; Relief ~1100 m Composition: Basalt to Rhyolite Estimated Volume = 460 km 3 >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 Oregon-Idaho:   Paleozoic-Mesozoic oceanic volcanic arcs   Accretionary complexes   Basinal successions Cenozoic volcanism:  Ignimbrite sweep  Flood basalts  Bimodal (modern)  High Lava Plains  Snake River Plain

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)

East Lake Big Obsidian Flow 1250 yrs BP Central Pumice Cone 7200 yrs BP

GEOMORPHIC ANALYSIS OF CINDER CONES STATEMENT OF THE PROBLEM Steve Taylor

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

Southeast Cinder Cone Field

Existing Methodology l Digital Geologic Map Compilation / GIS of Newberry Volcano (after McLeod and others, 1995) l GIS analysis of USGS 10-m DEMs  Phase 1 Single Cones/Vents (n = 182)  Phase 2 Composite Cones/Vents (n = 165) l Morphometric analyses  Cone Relief, Slope, Height/Width Ratio  Morphometric Classification l Volumetric Analyses  Cone Volume Modeling  Volume Distribution Analysis l Cone Alignment Analysis  Two-point Line Azimuth Distribution  Comparative Monte Carlo Modeling (Random vs. Actual)