Soil gases have been used for multiple scientific studies to explore topics such as microseepage, earthquakes, and gaseous exchange between the soil and the atmosphere. Microseepage refers to the limited release of hydrocarbons on the soil surface and can be used to look for petroleum deposits based on the assumption that hydrocarbons vertically migrate to the soil surface in small quantities. Migration of soil gases, specifically radon, can also be examined as earthquake precursors. Furthermore, for processes such as soil thawing and rewetting, for example, large sudden changes in soil respiration can cause increased flux of soil gases such as carbon dioxide and methane, which are greenhouse gases. These fluxes and interactions between soil gases and atmospheric air can further be analyzed by distance from the soil surface.