Figure 1. Generalized map of Oregon emphasizing the regional geologic, physiographic, and tectonic framework of Newberry Volcano. (After Walker and MacLeod, 1991). Locations of High Cascade volcanoes are identified as follows: MH = Mt. Hood, MJ = Mt. Jefferson, MW = Mt. Washington, TS = Three Sisters, CL = Crater Lake.

Co

ast

Ran

ge

Wes

tern

C

asca

des

K lam athMountains

Cas

cad

ia

S

ub

du

ctio

n

Zo

ne

Hig

h

Cas

cad

es

Basin and Range

1 0987

6

5

1

4 . 5 c m / y r

OwyheeUpland

Blue Mountains

Deschutes-UmatillaPlateau

Will

amet

te V

alle

y

High LavaPlainsW RFZ

BFZ

TFZ

Extent o f N ew berry Lava F low s N ew berry C aldera

R hyolite Isochrons (M a)9

Faults: TFZ = Tum alo Fault Zone W R FZ = W alker R im Fault Zone BFZ = B rother Fault Zone

M H

M J

T S

M W

C L

0 1 0 0 k m

4 2 N

4 4 N

4 6 N

1 2 4 W 1 2 2 W 1 2 0 W 1 1 8 W

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Figure 2. Generalized geologic map and photographic overview of Newberry Volcano (after Jensen, 2000). Top photo shows central caldera region and related cinder-cone field in foreground (red outlines). Bottom photo is an aerial view of the southeast cinder cone field (dashed box on map).

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O regon

StudyArea

Basalt and basaltic andesite flow s:early P le istocene to H olocene

R hyolite to dacite dom es, flow s, pum ice rings,and vent com plexes: early P le istocene toH olocene

Pum ice fa lls, ash flow s, and a lluvia l deposits:P le istocene to H olocene

Andesite Tuff (w est flank): P le istocene

B lack Lapilli Tuff (w est flank): P le istocene

A lluvia l deposits w ith in terbedded lap illi tu ff, ashflow tuff, and pum ice fa ll deposits: P le istocene

Tepee D raw Tuff (east flank): P le istocene

Basalt and basaltic andesite of sm all sh ie lds:P le istocene

F luvia l and lacustrine sedim ents: P le istoceneand P liocene(?)

Basalt, basaltic andesite , and andesite flow s, ashflow tuffs, and pum ice deposits of the C ascadeR ange: P le istocene

Basalt flow s and interbedded cinders and scoriadeposits: la te M iocene

R hyolite and andesite flow s, dom es, andpyroclastic rocks of P ine M ounta in: earlyM iocene

N ew berry C aldera com plex

C inder cones and fissure vents

Faults

0 5 km

Figure 3. Map showing distribution of the two morphometric classes of cinder cones identified by Taylor et al. (2003), as derived by analysis of 10-m digital elevation models. Group I cones (“younger”; n = 42) are statistically characterized by the following: avg. cone slope = 18.7o, avg. cone height = 127.7 m, and avg. cone height-to-width ratio = 0.19. Group II cones (“older”; n = 140) are characterized by: avg. cone slope = 12.8o, avg. cone height = 66.1 m, and avg. cone height-to-width ratio = 0.14. Morphometric differences between cone classes are statistically significant at the 95% confidence interval. Refer to Taylor et al. (2003) for an overview of techniques and results.

NewberryCaldera

0 5 km

Moprhometric Group I(Morphology RatingClasses 1, 2, and 3)

Morphometric Group II(Morphology RatingClasses 4, 5, 6, and 7)

Group I Cones

Group II Cones

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