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What's interesting to me is the size of the boulders on the right vs. the boulders on the left.
WHO PILED UP ALL THOSE ROCKS?
Roads and trails lead you through a jumble of stacked boulders where you can use your imagination to see unlikely shapes.
The rock piles began underground eons ago as a result of volcanic activity. Magma—in this case a molten form of the rock called monzogranite—rose from deep within the Earth. As it rose, it intruded the overlying rock, the Pinto gneiss formation.
As the granite cooled and crystalized underground, cracks (joints) formed horizontally and vertically. The granite continued to uplift, where it came in contact with groundwater. Chemical weathering caused by groundwater worked on the angular granite blocks, widening cracks and rounding edges. Eventually the surface soil eroded, leaving heaps of monzogranite scattered across the land like careless piles of toy blocks.
The monzogranite developed a system of rectangular joints. One set, oriented roughly horizontally, resulted from the removal—by erosion—of the miles of overlying rock, called gneiss (pronounced “nice”). Another set of joints is oriented vertically, roughly paralleling the contact of the monzogranite with its surrounding rocks. The third set is also vertical but cuts the second set at high angles. The resulting system of joints tended to develop rectangular blocks. https://www.nps.gov/jotr/learn/nature/g ... r%20joints.
WHO PILED UP ALL THOSE ROCKS?
Roads and trails lead you through a jumble of stacked boulders where you can use your imagination to see unlikely shapes.
The rock piles began underground eons ago as a result of volcanic activity. Magma—in this case a molten form of the rock called monzogranite—rose from deep within the Earth. As it rose, it intruded the overlying rock, the Pinto gneiss formation.
As the granite cooled and crystalized underground, cracks (joints) formed horizontally and vertically. The granite continued to uplift, where it came in contact with groundwater. Chemical weathering caused by groundwater worked on the angular granite blocks, widening cracks and rounding edges. Eventually the surface soil eroded, leaving heaps of monzogranite scattered across the land like careless piles of toy blocks.
The monzogranite developed a system of rectangular joints. One set, oriented roughly horizontally, resulted from the removal—by erosion—of the miles of overlying rock, called gneiss (pronounced “nice”). Another set of joints is oriented vertically, roughly paralleling the contact of the monzogranite with its surrounding rocks. The third set is also vertical but cuts the second set at high angles. The resulting system of joints tended to develop rectangular blocks. https://www.nps.gov/jotr/learn/nature/g ... r%20joints.