21. On top of this basement rock , Permian and Mesozoic sedimentary and volcanic rocks were deposited. 22. This formation is not exposed in the park, though it does form its basement rock . 23. As such, the basement rock can become younger going closer to the edge of the continent. 24. These basement rocks were created during the late Mesozoic era, long before the Itcha Range formed. 25. These tuffs lie directly on the basement rocks . 26. The Lower Peninsula is dominated by a Gladwin County where the Precambrian basement rocks are deep. 27. Basement rock was formed during the Hercynian orogeny when a strong regional metamorphism affected the area.28. This fate the Pi�gut-Pluviers granodiorite shares with many other crystalline basement rocks in the Massif Central. 29. This isotope signature may be the effect of assimilation of deeper basement rocks during magma formation. 30. Typically, the temperature in those vast regions of the accessible crystalline basement rock increases with depth.
