Apply Grey Relation Analysis to Identify and Characterize Inter-well Interference Based on the Tracer Monitoring in the Mahu Sag

Abstract

For the unconventional reservoirs, advances in drilling and fracturing technologies prompt operators to tend to the designs of large-scale, staged fracturing with multi-cluster in one stage. However, with the well spacing getting closer, it must be noted that the risk of inter-well interference increases since the hydraulic fractures can interfere, even hydraulically communicate. In the past few years, inter-well interference became more prominent and thus received significant attention in the development of unconventional reservoirs. The interferences in fracturing to adjacent wells have negative effects as: (1) abnormal changes in wellhead pressure, daily gas production and daily water production of adjacent wells; (2) water flood out, mud backflow or sand production, etc. In some extreme cases, production wells may never fully recover or stop production permanently.2 will increase the risk of casing deformation in horizontal wells.