Transcript Document

The Idaho Batholith
Kevin Kwong
Andrew McCauley
Trapper Peak, Bitterroot Mountains; 10,157’
http://geology.about.com/library/bl/maps/n_statemap_ID.htm
http://photosunion.com/photos/Trapper-Peak-Bitterroot-Mountains-Montana/
(Snee et al. 1995, fig. 10.28)
(Foster et al. 2001, fig. 17)
(King and Valley 2001, fig. 8)
Field photos of migmatite from eastern
pluton border. A) ptygmatic granite veins
feeding larger granite mass. B) anatectic
plg, kspar, qtz, in gneiss. C) Anatectic vein
with biotite. D) deformation enhanced
melt migration suggested by vein size
increase from right to left.
(Foster et al. 2001, fig. 4)
(Foster et al. 2001, fig. 12)
VELOCITY STRUCTURE AND LITHOSPHERE CONSTRAINTS
OF THE IDAHO BATHOLITH REGION
Figure Above: Map of Moho depth derived from H −
stacking analysis. Red colors denote shallower Moho, blue
colors denote deeper Moho. Geologic provinces include
Cascade volcanic arc (CM), Blue Mountains (BM), High
Lava Plains (HLP), Columbia River basin (CRB), Snake
River Plain (SRP), Idaho batholith (IB), Owyhee Plateau
(OP), Modoc Plateau (MP), and Great Basin (GB)
Eagar et al. 2011
Figure Above: Cross sectional view through tomographic
model. Warm colors represent regions of reduced
velocities and cool colors represent regions of increased
velocities.
Roth et al. 2008
Porphyry Molybdenum deposits of the Idaho
batholith area. (Worthington 2007, fig. 2)
Figure Above: Tectonic model. A: During middle Cretaceous
time, full magmatic arc developed in western Idaho . B: In Late
Cretaceous time, while magmatic arc was still active,
transpressional deformation in western Idaho shear zone
resulted in east-west shortening.
(Giorgis et al. 2005, fig. 4)