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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