Very few I suspect. My hope for Amal is that this scary-skinny phase is a passing one and she'll relax into her marriage and return to the lovely, wonderfully winsome creature whom Clooney fell in love with. She doesn't need to be an alpha female competing with other women. She's already won the jackpot.
Earth's crust is Earth's hard outer layer. It is less than 1% of Earth's volume. The crust is made up of different types of rocks: igneous, metamorphic, and sedimentary rocks. Below the crust is the mantle. The upper part of the mantle is made up of peridotite, a rock denser than rocks common in the crust. The crust and the upper mantle make up the lithosphere.
In fact, igneous and metamorphic rock make up 90 to 95 percent of the top 16 kilometers (10 miles) of the earth's crust. So sedimentary rock makes up less than 10% of the crust. It is very rare that sedimentary rock structures extend more than 4 or 5 miles deep.