What is the typical runoff result when water comes into contact with pyrite at the earth's surface?

When water comes into contact with pyrite, a mineral also known as iron sulfide, it can lead to the production of acidic runoff. This occurs primarily through a process called acid mine drainage, which happens when pyrite is exposed to oxygen and water. The oxidation of pyrite generates sulfuric acid as a byproduct. This acid formation lowers the pH of the surrounding water, causing it to become acidic.

The conditions become more acidic due to the dissolution of pyrite, leading to increased concentrations of hydrogen ions in the water. This acidic runoff can have significant environmental impacts, particularly in areas where mining occurs, as it can lead to the leaching of heavy metals into surrounding ecosystems, affecting both soil and water quality. The resulting acidic conditions can harm aquatic life and lead to increased corrosion of infrastructure.

Understanding this process is crucial in geology, especially in the context of environmental geology and the impact of mineral weathering on water quality.