Those coccoliths also make for fantastic oil bearing reservoir rock, provided certain conditions are met, otherwise chalk tends to make a good seal. Some of the most prolific oil fields in the world, in the north sea, come from fractured chalk beds.
For example, massive salt diapirs (think of them as giant, mountain sized fingers) 5-15 miles beneath the earth's surface are gradually squeezed, like a fluid, moving upwards and fracturing rock (and chalk) above, creating porosity and permeability necessary for oil production.
For example, massive salt diapirs (think of them as giant, mountain sized fingers) 5-15 miles beneath the earth's surface are gradually squeezed, like a fluid, moving upwards and fracturing rock (and chalk) above, creating porosity and permeability necessary for oil production.