Lower temperature and pressure during the diagenesis process compared to other modes of hydrocarbon generation result in a lower maturation level of oil shale. Continuous burial and further heating and increased pressure over time could result in the conventional production of oil and gas from the oil shale source rock. The largest deposits are found in the remains of large lakes such as the deposits of the Green River Formation of Wyoming and Utah, USA. Large lake oil shale basins are typically found in areas of block faulting or crustal warping due to mountain building. Deposits such as the Green River may be as much as and yield up to 40 gallons of oil for each ton (166 l/t) of shale.