Study on Fracability of Tight Reservoir on the basis of Geophysical Logging: a Case Study of Chang 7 Formation in Longdong Area, Ordos Basin

Abstract

Fracability is the ability to form complex fracture to Increase production in tight reservoir under the same fracturing condition. The factors influencing fracturing include reservoir brittleness, fracture toughness, crack system,thermal evolution andmineral content etc. The tight reservoir physical property are poor, and the oil and gas produced under natural conditions is too little, so it is necessary to fracture the reservoir.In this paper, the brittleness and fracture toughness of Chang 7 Formationof Ordos Basinare calculated by logging data under the constraint of laboratory data. In combination with production practice, a new analysis model of reservoir hydraulicfracturing is constructed. The new analysis method is used to evaluate the fracability of Chang 7 stratum in the Ordos Basin, which ranges from 38.7% to 51.4%. It is basically consistent with the practical fracturing effect of typical wells in this area, which shows that the new method is accurate in calculation, convenient in field application, and can provide experience for the reservoir hydraulic fracturing .