SEDIMENTARY ROCK

- Eons ago, inland seas washed the area of the Great Plains and Rock Mountains, depositing thousands of feet of sand, mud, silt, clay and marine fossils. Later these deposits emerged from the water as Sedimentary Rock. 70 to 35 million years ago, stresses and plate pressures caused seams and cracks to form in the sedimentary formation.

MAGMA, BATHOLITHS and STOCKS

- Magma (igneous molten rock) from the mantle beneath the earth's crust began to surge upward into the lower ares of the cracked and layered rock about 35 million yeares ago. When magma spreds, dissolves, cools and hardens beneath the earth's surface (Intrusive), it creates huge horizontal "Batholiths" of granite, syenite, etc. (Metamorphism). Smaller "Batholiths" are called "Stocks", of which the Spanish Peaks are formed. Several miles of sedimentary rock covered the Spanish Peaks "Stocks" at the time. In the last 35 million years, uplifts and folds occurred, raising the surface of the land. Rain, frost, wind, and ice wore away the softer overlying sedimentary rocks, exposing the hard igneous rock (Stocks) of the Spanish Peaks. Lava is also molten magma, but it has reached the earth's surface (Extrusive) in the form of volcanoes, lava flows and cinder cones. Although the Spanish peaks are not extinct volcanoes, the surrounding area is marked by many volcanic mountains and lava flows, some of which have been active as recently as 10,000 years ago.

DIKES

- While the molten magma was rising to create the horizontal underground "Stocks", the magma squeezed into vertical cracks and joints, spreading out like spokes on a wheel. Again the elements wore away the softer material, exposing the hard Basalt of the "Dikes" which vary from 1 to 100 ft. wide and up to 14 miles long. The "Dikes" are a prominent feature at Spanish Peaks. In fact, nowhere else are these geological phenomena found in these patterns, in such variety of rock type or in as great length, height, abundance or beauty. The Spanish Peaks "Dikes" are known to geologists world-wide. The only other formations that approximate this perfection are found in Siberia, USSR.

CIRQUES (Serks)

- "Cirques" are circular basins at valley heads where valley glaciers originated in a much colder period of time. The amphitheatre-like rock-form above the Scout Ranch is a beautiful example of a "Cirque"". As the glacier melts and slowly moves down the valley, it plucks out chunks of bedrock and breaks off projections, carrying rock and fragments down hill, leaving a basin on the side of the mountain.

MORAINE

- Long low ridges of rock and residue deposited along the side of sliding, melting glaciers are called "Moraine". Occasionally the "Moraine" is pushed up in front of the glacier, leaving lakes in the "Cirque". The "Cirque" above the Scout Ranch has no lake, but no doubt has water or springs under the boulders that help feed Bear Creek which runs through the middle of the Camp.

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