Structural fractures play significant roles in the reservoirs lacking porous and permeable channels, like the volcanic/subvolcanic rocks. Hence, prediction of fractures plays a key role in the exploring and producing hydrocarbon in these kind of rocks.

Both stress and strain energy are involved and both should be taken into consideration when structural fractures are formed. As am improved method, Bio-factor Method employs both stress and strain energy for the fraction predictions.

The results of predicted fracture density derived from Bio-Factor Method are more accurate than the fracture value and strain energy value. Areas with high potential of structural fractures are blocked out and recommended for petroleum exploration.

Pre-existing fault system dominantly influences the stress field and strain energy condition which sequentially controls the distribution and development of structural fractures.