11. As the heat causes it to expand, the crust gradually thins; melted crustal rock , called rhyolite, forms bulges near the surface. 12. In metamorphic rocks, coesite was initially described in eclogite xenoliths from the crustal rocks are carried to depths of or more. 13. Small protocontinents ( cratons ) formed as crustal rock was melted and remelted by hot spots and recycled in subduction zones. 14. Upper lavas were partly contaminated with crustal rocks as magmas from the mantle plume passed through the lower and upper crust. 15. Water has a density of 0.433 lbs / sqin and upper crustal rocks has a density of 2.7gms / cm ^ 3. 16. When they rupture, huge slabs of crustal rock rush toward the surface or dive deeper with the speed of a rushing locomotive. 17. His argon-dating technique involved stepped pyrolysis of the rocks to force out the argon, then determining the crustal rocks from the Earth. 18. In continental crustal rocks , biotite may break down at high temperatures to form orthopyroxene + potassium feldspar + water, producing a granulite. 19. The lithosphere, however, only refers to the uppermost layers of the solid Earth ( oceanic and continental crustal rocks and uppermost mantle ). 20. That means the dynamo died and what is left is the memory of that dynamo, stored in the crustal rocks like a magnetic tape recording.
