Well logs which present the full wave train of the acoustic signal show variations in both the compressive and shear wave arrivals with lithological changes. This information, along with elastic constants, which can be derived from the logs, can be used in the design techniques available for well stimulation planning.
This information has been successfully applied in one area of California to select completion intervals that could be successfully stimulated at pressures below wellhead limitations. Additionally, pressures below wellhead limitations. Additionally, this data could be applied to the prediction of fracture height and of the fracture closure or sand embedment problem where productivity increases from well stimulation are only temporary.
Optimization of well treatment over recent years has necessitated more exact input data regarding the formation characteristics. Design techniques have been developed which require specific rock properties; however, many of the properties used properties; however, many of the properties used are assumptions or average values obtained from limited core samples. Variations of geological factors under downhole conditions are readily observed on many types of logs; however, many of these variations are seldom taken into account in treatment design. Their influence on vertical fracture height is an important consideration for which there has been nothing very consistent in the method of prediction.
