Comparative Analysis of Stimulations in the Eastern Gas Shales

摘要

In this project, sixty-two wells in eight states have been stimulated by massive hydraulic fracturing, cryogenic fracturing, foam fracturing, displaced chemical explosives and novel techniques. Two of the novel stimulations used (1) nitrogen alone and (2) oil assisted with nitrogen. The other two novel treatments unsuccessfully attempted (1) an open hole packer staged frac and (2) a kerosene frac. These two were mechanical and conceptual failures. Details of the stimulations and production data have been compiled and studied. The limited data available in regions of similar geologic factors preclude a thorough analysis on the stimulation effectiveness. However, the experience that has been gained has established trends which may prove helpful to those who are considering stimulation technology in future well drilling ventures in the shale. This document describes the methods employed, the results obtained, the variables used, the production observed and the conclusions offered. These data substantiate the fact that the stimulation methodology of naturally fractured reservoirs is not yet established for all regions within the shale basins. The strategy that appears to be plausible is merely to link the wellbore to the natural fracture system that is the gas reservoir in the shale formation. Much more synthesis of geologic data are required to identify shale gas prospects. In geographical regions where the natural fractured density is characterized as relatively high, this linkup can be achieved by a multidirectional stimulation technique such as a borehole shooting as well as a conventional size foam fracturing treatment. In regions characterized as having a sparse natural fracture system, the apparent cost effective stimulation method is foam fracturing.