what is newberry volcano?
Post on 29-Jan-2016
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DESCRIPTIONWhat is Newberry Volcano?. Julie Donnelly-Nolan, USGS Menlo Park CA,. Tim Grove, MIT, & Rick Carlson, Carnegie Institution. View of Newberry edifice from the northeast. view south of the Newberry edifice from Bend, Oregon. Cascades or not? High Lava Plains volcano? - PowerPoint PPT Presentation
What is Newberry Volcano?Julie Donnelly-Nolan, USGS Menlo Park CA, Tim Grove, MIT, & Rick Carlson, Carnegie InstitutionView of Newberry edifice from the northeast
view south of the Newberry edifice from Bend, Oregon Cascades or not? High Lava Plains volcano?
Is it a volcanic field, not a volcano?
Cascades arcnot equal to Cascade Range
Newberry Volcano Sited at the Intersection of the Cascadesand the High Lava Plains Magmatic ProvinceColored Regions Show Volcanic Deposits Younger than 17 Million Years (Smith and Luedke, 1984)South Sister, OregonDiamond CratersCascadesNewberry
ThreeSistersNewberry marginNewberry edifice
Newberry lavascover ~3000 km2For comparison,MSH
10 m DEMFocused onNewberry Caldera
view from Paulina PeakAt least 3 calderas, 300 ka - 80 ka
View of Paulina Peak from Paulina LakeHighest point on caldera rim is Paulina Peak atnearly 8000 ft.,~4000 ft. higherthan surroundingterrain
Slide courtesy of Mike PolandMedicine Lake volcanoNewberry Volcano
Newberry VolcanoMedicine Lake volcano
Geologic Map of Newberry VolcanoBy MacLeod, Sherrod,Chitwood, & JensenQbaScanned map courtesy of Templeton, Taylor, Giles,& Rowe (WOU, OSU)~35 mapped Newberry units
field assistant& MazamaField challenges --& lots of similar rocks
The Subduction Contribution87Sr/86Sr = 0.70317187Os/188Os = 0.151887Sr/86Sr = 0.70382187Os/188Os = 0.1922Sr = 1124 ppmSr = 300 ppm~4% H2O(Carlson data)
(Carlson isotope data)
What is the Subduction Component?(Carlson data)
He isotope dataGraham, et al.JVGR 2009
NVGrove et al. model
WVFFigure adapted from B. Jordan PhD thesis
than HLP rhyolitesNewberry rhyolites are lower in SiO2
A subduction-related volcano, not an HLP volcanoCalc-alkaline basalts as well as HAOT-type basaltsIs isotopically like Cascades lavasLies behind the arc axis = rear-arc volcanoExtensional terrain; strong magmatic focusEdifice with central caldera eruptions; not a volcanic field
Tectonic settingOf Newberry:interaction of tectonism and volcanism akey featureHigh Lava PlainsCrater LakeMt. JeffersonWVF
From Donnelly-Nolan et al., JVGR 2008Fore-arc, arc axis, & rear-arc volcanoesBehind-the-arc QuaternaryvolcanismInterpretation:
Preliminary version of Newberry geologic mapping will be ondisplay Monday at poster booth 288View of Newberry edifice from the southeastAcknowledgments: with thanks to Robert Jensen, Dave Ramsey, Duane Champion,Andy Calvert, Marvin Lanphere, Larry Chitwood
*View of Newberry Volcano from the northeast.**Just to show what type of normalized incompatible element patterns go with the extremes of major element composition.****Just to make the point that the sediment component has 87Sr/86Sr of about 0.7037. Cant have a big component of old sediment.