What is eutrophication? what can speed it up?

This is the process by which a body of water acquires  a high concentration of  nutrients, especially phosphates and nitrates. These typically promote excessive growth of algae. As the algae die and decompose, high level of organic matter and the decomposing organisms deplete the water of oxygen, causing the death of other organisms such as fish.

Eutrophication is  a natural, slow-aging process for a water body  but human activity greatly speeds up the process  e.g. through  much use of agricultural fertilizers that contain nitrogen and phosphorous which get carried away in run off water and in to waterways.

the rocks are classified by the geological process they are formed by. the three main groups of rocks are igneous, metamorphic, and sedimentary. minerals are not they are classified under the chemical classes they are in. these groups include silicates, sulfates and carbonates.