Introduction to Earth Sciences I
1.3 The Earth's Strength
Although it is a fundamental quantity of any material object, the question, "how strong is the Earth" was not really addressed very closely until fairly recently. The answer, it would seem on first thought, is that it is almost infinitely strong - at least the rocky parts of the continents. For most common purposes, the Earth is indeed very strong. However, we are fairly confident that the Earth's (outer) core is liquid and that volcanic rocks rise from deep in the Earth so we know that it is not completely rigid through and through. We also know from the bulging middle shape that it must be somewhat soft in gross properties. How can we get an idea of the Earth's strength? The answer is that there are several ways.