Experimental study and application of seepage characteristics of chang 72 tight oil reserves in ordos basin

Abstract

Accounting for more than 80% of total global resources of unconventional energy development, the effects of conventional oil and gas exploration grows worse and is gradually becoming a global cause for concern. Efforts and methods to ensure rapid development of special reserves have become the strategic issue affecting the development of global oil and gas industry. Tight oil is considered to be the most significant and realistic resource. Tight oil reservoirs are characterized by low porosity (typically less than 7%) and permeability (less than or equal to 0.1 mD). The average single well production capacity is low and therefore it is difficult to achieve effective high production rates by employing the conventional development methods. This articles examines tight oil reserves in Chang 7₂ in Ordos Basin Oilfield. To achieve the aim of exploiting the tight oil reservoir efficiently, laboratory experiment and theoretical model was adopted. The mathematical model which provides a theoretical basis for the optimization of the field, that is, for the development of tight oil and vertical well fracturing was analyzed. It is concluded that the productivity of vertical well fracturing is low and rapidly decreases, which is not an economical and effective way of production. The use of staged fracturing in horizontal wells is proposed.