Abstract: Methods and systems are described for measuring effects of a hydraulic fracturing process. The techniques can utilizes cross-well seismic technology, such as used in Schlumberger's DeepLook-CS tools and service, or in some case surface to borehole or borehole to surface seismic technology. The downhole seismic sources at known locations can be conventional sources or can be other types of equipment operating at known locations such as perforation guns. The source is activated or swept creating energy which is transmitted through the formation. The energy is recorded at the receiver array and processed to yield a tomographic image indicating changes in the subterranean formation resulting from the hydraulic fracturing process. The process can be performed pre and post hydraulic fracture stimulation to generate a difference image of propped fractures in the reservoir.