Figure 5.6 The phosphorus cycleSULFUR CYCLE
Elemental or pure sulfur is commonly found in underground deposits or near
natural hot springs or volcanoes. It’s also found in the combined form in many
minerals.
Sulfur in the Lithosphere
The sulfur content of rocks varies considerably (e.g., sedimentary rocks have the
most while igneous rocks have the least). Sulfur in the lithosphere is mobilized
by slow weathering of rock material. Dissolved in runoff, it moves with river
water and is deposited as sediments in the oceans. Eventually it uplifts to the
surface again, thus completing the geological part of the sulfur cycle.
Sulfur in the Hydrosphere
The main storage of sulfur in the oceans is through dissolved sulfate. The most