Abstract:

Hydraulic fracturing, an important cracking mean of the crust, plays an important role in the migration of the petroleum and in the hydorcarbon seeping process from source rocks. Research on micro-characteristics of the cores which are cracked by water power is rather weak, and their forming mechanism is only restricted within theoretic discussion in addition to relatively few supports from interrelated experiments. Hydraulic fracturing experiments were conducted using composite samples consisting of micrite (muddy siltstone)  sandstone in order to understanding relationship between  hydraulic fracturing and rock types in sedimentary basin. The lower permeability rocks,micrite and muddy siltstone which modeled the crust of overpressure system have been broken by overpressure fluid, while the sandstones modeled the uncompacted belt of overpressure system have been not broken. The experimental results coincide with the theoretical analysis and field observation of hydraulic fracturing.

Key words: hydraulic fracturing, genetic analysis, physical modeling