Oil and gas zone boundaries can be established using vitrinite reflectance data. The boundaries are approximate and vary according to kerogen type. [[:file:evaluating-source-rocks_fig6-7.png|Figure 1]] shows the approximate boundaries for kerogen types I, II, and III. Time-temperature relationships and mixing of various sources of organic matter may alter these boundaries. | Oil and gas zone boundaries can be established using vitrinite reflectance data. The boundaries are approximate and vary according to kerogen type. [[:file:evaluating-source-rocks_fig6-7.png|Figure 1]] shows the approximate boundaries for kerogen types I, II, and III. Time-temperature relationships and mixing of various sources of organic matter may alter these boundaries. |