Torres del Paine vs. Split Mountain — 3 — Comparison
View to the west from Mirador Britanico, Torres del Paine National Park. Left to right, Paine Grande, North Summit of Paine Grande, Cerro Castillo, Cota Dos Mil, and Catedral. The North Summit-Cerro Castillo transition marks the steep margin of the granite laccolithic complex.
Aerial view of area south of Split Mountain and Cardinal Peak, including Mount Pinchot (left), Striped Mountain (center-right), and Goodale Mountain (right), from ~3000 m altitude. Here, the prominent granite is Cretaceous and overlies coeval layered diorites, as in Torres del Paine. Mount Pinchot and the dark rocks at right-center are a continuation of the metamorphic screen under Split Mountain, and the Cretaceous Striped pluton likely sits above this screen in a manner similar to the Tinemaha Granodiorite on Split Mountain. See Bartley et al. (2012) for details.
Cuernos del Paine in Torres del Paine National Park, Chile, and Split Mountain, Sierra Nevada, California, bear a great resemblance to one another. For example:
In both areas leucocratic granite (Miocene at Cuernos, Jurassic at Split) are roofed by dark brown metaclastic rocks (Cretaceous at Cuernos, Cambrian at Split) and these roofs are subhorizontal over several square km.
Both complexes are cut by numerous dikes (Miocene at Cuernos, Jurassic at Split).
Granites in both areas sent dikes and sills into the overlying metamorphic rocks, but…
…in neither area can one find blocks of the roof rocks in the granites. This is particularly well shown owing to the high color contrast between the dark metamorphic rocks and the light-colored granites.
So why did Torres del Paine develop km-tall cliffs and truly remarkable scenery, whereas Split Mountain is merely…well…a jagged 4300m peak bounded by km-tall cliffs…OK, Split Mountain is pretty spectacular, too, but it lacks the remarkable spires found at Torres (see top photo above). This difference is likely due, at least in part, to tectonic differences. Torres del Paine lies in a relatively quiet area, tectonically speaking, whereas Split Mountain lies along the Sierran crest and is bounded on the east by the extensional frontal fault system of the range. Rocks east of the crest have been pulverized by faulting, and this is evident in the intense vertical jointing in the leucogranite. By contrast, faulting at Torres is minor, and the rocks have widely dispersed joints.