PIKES PEAK GRANITE
One of the most visited mountain peaks in the American
Cordillera is central Colorado's Pikes Peak (it is supposed to be spelled ÒPikeÕs
PeakÓ, but it is deliberately misspelled "Pikes Peak"). The
rocks of this mountain & surrounding area represent the Pikes Peak
Batholith, a fairly large, late Mesoproterozoic-aged igneous intrusion that
was emplaced 1.08 billion years ago. Published research on the Pikes Peak
Batholith has shown that several igneous facies are present (e.g., Hutchinson,
1987).
Pikes Peak (looking W from between Colorado Springs and Manitou Springs).
All of the pinkish-red rocks are granites of the Pikes Peak Batholith
(1.08 b.y.).
Eastern side of summit of Pikes Peak (looking ~SSW) & granites of the Pikes Peak
Batholith (1.08 b.y.).
View from Pikes Peak summit (looking ~E toward the Great Plains & Colorado
Springs urban area).
Pikes Peak Batholith (looking ~ESE) - 1.08 b.y. coarsely-crystalline,
porphyritic granites (pgpm2 facies) a little east of the summit house of Pikes
Peak.
View from Pikes Peak summit (looking ~NNE toward the Front Range).
Pikes Peak Granite (pgpm2 facies) from a little east of the summit house
of Pikes Peak. This facies is coarsely- to very coarsely-crystalline and
porphyritic. It is dominated by K-feldspar, quartz, and biotite mica
Pikes Peak Granite (pgpf dike facies) (left: 6.0 cm across at its
widest; right: 6.1 cm across at its widest) from next to the summit
house of Pikes Peak, west of Colorado Springs, western El Paso County, central
Colorado, USA (38¡ 50Õ 29Ó N, 105¡ 02Õ 29Ó W). This facies is finely-crystalline,
porphyritic, and reported to be fluoritic.
Pikes Peak Granite (pgpm2 facies) (12.0 cm across) from a little east of
the summit house of Pikes Peak. This facies is coarsely- to very
coarsely-crystalline and porphyritic. It is dominated by K-feldspar,
quartz, and biotite mica.
Pikes Peak Granite (pgmc facies) (10.5 cm across) from the parking lot
for the Pikes Peak Cog Railway on the western side of the town of Manitou
Springs, eastern base of Pikes Peak, western El Paso County, central Colorado, USA
(38¡ 51Õ 20Ó N, 104¡ 55Õ 58Ó W). This facies is coarsely-crystalline and
porphyritic. It is dominated by K-feldspar, quartz, and some biotite
mica.
Reference
cited:
Hutchinson, R.M. 1987. Granite-tectonics
of the Pikes Peak intrusive center of Pikes Peak composite batholith,
Colorado. Geological Society of America Centennial Field Guide 2:
331-334.