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This granite process (especially the joints) is so evident on this granite hillside.
Geologists believe the face of this modern landscape was born more than 100 million years ago. Molten liquid, heated by the continuous movement of the Earth's crust, oozed upward and cooled while STILL BELOW the surface. These plutonic intrusions are a granitic rock called monzogranite.
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.
Geologists believe the face of this modern landscape was born more than 100 million years ago. Molten liquid, heated by the continuous movement of the Earth's crust, oozed upward and cooled while STILL BELOW the surface. These plutonic intrusions are a granitic rock called monzogranite.
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.