... blasting by drilling deep holes. It is found that: The scope and depth influenced by blasting on the preserved rock mass at lateral side and in the direction of back wave are quite big, especially surface layer of the rock mass is badly damaged with cracking by pulling force. vertical wall main...

... of those achieved in the field. In a sandstone of moderate strength, uncased mainbore and laterals (Levell) are predicted to be stable for the anticipated reservoir depletion .. Sta- bility of Level 2 multilaterals (cased mainbore, uncased lateral) in a weaker sandstone was shown to be dependent...