Urbancic, Ted and Shumila, V. and Rutledge, James T. and Zinno, Richar J. Determining Hydraulic Fracture Behavior Using Microseismicity. In: In Proceeding of the 37th U.S. Rock Mechanics Symposium, Vail, Colorado, USA, June6-9, 1999. American Rock Mechanics Association, pp. 991-997.
Full text not available from this repository.Abstract
Temporal-spatial variations in event locations and in frequency-magnitudeparameters (seismic activity level and b-value) are evaluated for a catalogue of 994microseismic events (-1.9 ≤ M ≥ -0.2) associated with the Cotton Valley (East Texas,USA) fracture treatment of May 14, 1997. The treatment was carried out between 2756and 2838 m depth and consisted of three separate injection phases. Event locationswere obtained based on P- and/or S-wave arrivals and direction vectors, to an accuracyof 14 to 24 m.. Spatially, the event locations were contained within the perforationinterval, and outlined a hydraulic fracture 560 m in length and 60 m in width, that wassymmetric about the treatment well (TW), and followed the predicted N70E trend.Nearly 50% of the events occurred over the short interval 90 m to 120 m east of TW.Over this interval, b-values, as calculated between–1.5 ≤ M ≥ -0.4, were above 1 duringthe initial two injections, and seismic activity levels, evaluated at M = -0.8, increasedrelative to other parts of the fracture. During the third injection, the fracture growtheastwards was accompanied by b-values above 1. To the west of TW, b-values rangedfrom 0.5 to 1 for all three injections, however, the third injection was accompanied by anincrease in seismic activity. Based on these observations, we suggest thatmicroseismic event locations can be used to define the overall dimensions of thehydraulic fracture, and that frequency-magnitude parameters can potentially be used toidentify differences in fracture growth and failure mechanisms.
Item Type: | Book Section |
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Subjects: | Methodology > Other-additional study Region > USA > Texas > Cotton Valley Inducing technology > Unconventional hydrocarbon extraction |
Project: | SERA > COTTON VALLEY: uconventional hydrocarbon extraction |