Silver Mountain

Silver Mountain was so well known for its radiating dikes that for much of its early history it was known as Dike Mountain. The name changed when silver and gold were discovered along its flanks in the 1870's.


*Aerial view of Silver Mountain with red arrows pointing to some of the dikes that radiate outward from the igneous plug that forms the core of the mountain. Click image to enlarge.*	*Simplified geologic map of radiating dikes at Silver Mountain. The red center is a plug and the red lines are dikes radiating outward.*


On-the-ground view of some of the dikes (red arrows) on the southeast side of Silver Mountain. Click image to enlarge.

Silver Mountain was never the source of large amounts of valuable ore. Today the land is leased for cattle and horse grazing. It provides spectacular scenery for travelers over La Veta Pass on their way to the San Luis Valley, and is valuable habitat for herds of Rocky Mountain Bighorn Sheep and many other wildlife species.


View southward of Silver Mountain (foreground) and East and West Spanish Peaks. Black arrow points to the town of La Veta. Red arrows highlight a few of the more than 500 dikes that have been mapped in the area.

References

Spanish Peaks dikes

H. Ode, Mechanical analysis of the dike pattern of the Spanish Peaks area, Colorado, Geol. Soc. Am. Bull. 68 (1957) pp. 567-576.

O.H. Muller, Changing stresses during emplacement of the radial dike swarm at Spanish Peaks, Colorado, Geology 14 (1986) pp. 157-159.

O.H. Muller, D.D. Pollard, The stress state near Spanish Peaks, Colorado, determined from a dike pattern, Pure Appl. Geophys. 115 (1977) pp. 69-86.

R.B. Johnson, Patterns and origin of radial dike swarms associated with West Spanish Peak and Dike Mountain,
south-central Colorado, Geol. Soc. Am. Bull. 72 (1961)
pp. pp. 579-590.

Penn, B. S. and Lindsey, D.A. 1996. "Tertiary Igneous Rocks and Laramide Structure and Stratigraphy of the Spanish Peaks Region, South-Central Colorado: Road Log and Descriptions
from Walsenburg to La Veta (First Day) and La Veta to Aguilar (Second Day)," GSA Special Publication #44, Geologic Excursions to the Rocky Mountains and Beyond, Fieldtrip Guidebook for the
1996 Annual Meeting, Geological Society of America, Denver, Colorado, Oct. 28-31. Ren A. Thompson, Mark R. Hudson, and
Charles L. Pillmore (eds.)

Penn, B.S., Snee, L.W., Wendlandt, R.F., and Unruh, D. "Geochemical Evolution of the Spanish Peaks Intrusive Rocks
of South-central Colorado," Geological Society of America - Rocky Mountain Sectional Meeting Abstracts, May 4-6, 1994, Durango, Colorado, vol. 26, no. 6, p. 58.

Penn, B.S., Wendlandt, R.F., Simmons, E. C., and Unruh, D.M. 1999. The Petrogenesis of the Spanish Peaks Intrusive Rocks of South-Central Colorado, GSA Abstracts with Programs, Vol. 31, No. 7

Last Updated: 10/25/2012 1:46 PM