They are found in upwelling areas, especially where the oxygen minimum zone intersects the ocean floor. Phosphorite deposits now on land are mined for fertilizer. Glauconite is a greenish hydrous silicate of complex and variable composition typically found on topographically high areas near the coast. It may form green sands or green muds. Carbonates are mostly biogenic, but nonbiogenic carbonates appear to be forming on the Bahama Banks due to unique conditions of temperature, pressure, and productivity.
Zeolites give abyssal red clay deposits their color, particularly in the Pacific.
Cosmogenous sediments are particles that originate in outer space. Iron spherules and silicate condrules are formed in the asteroid belt. There is significant evidence for meteor impacts to Earth's surface during the past. Neritic sediment deposits are found near the continents and show a wide range of sizes. They are mostly lithogenous sediment entering at the shore, and are distributed across the continental shelf and down the slope by waves, currents and turbidity currents.