THE QURAN EXPLAINS GEOLOGY

The Challenge of The Qur’an ~ 365 ~ constituents and elevations of their upper surfaces are significantly different. This means that an excess of mass seen as material above sea level, as in a mountain system, is due to a deficit of mass, or lowdensity roots, below sea level. “In the theory of isostasy a mass above sea level is supported below sea level, and thus there is a certain depth at which the total weight per unit area is equal all around the world; this is known as the depth of compensation” (V/458). The apparent unchangeability of the mountains— the ‘immovable mountains’ of the Quran—is explained by the Encyclopaedia Britannica (1984) in terms of this naturally occurring balance: “Most of the Earth’s crust is approximately in hydrostatic equilibrium in this way, so that when erosion occurs and rivers transport large quantities of weathered material away from the upland areas to be deposited in the oceans, there is a tendency for the hinterland to rise isostatically, and for the adjacent ocean floor to sink” (6/44).