Method and apparatus for determining fracture zone in rock formation

Abstract

The invention discloses a method and device for determining a fractured zone in a rock formation. The method comprises: setting a pressure sensor for obtaining pressure information of fracturing fluid in a perforation section corresponding to a fracturing pipe string; injecting a pressure sensor into the fracturing pipe string Fill up the fracturing fluid, then inject the fracturing fluid with a predetermined displacement, suppress the bottom hole with the formation fracture pressure, and form the first artificial fracture segment; and use the pressure sensor to obtain the current first pressure curve segment; continue to Injecting fracturing fluid at the predetermined displacement so that the first artificial fracture segment extends forward; and using the pressure sensor to obtain the current second pressure curve segment; when the fracturing fluid loss rate is greater than the injection rate, and the When the current pressure acquired by the pressure sensor suddenly drops, it means that the first artificial fracture segment is connected to the broken zone. The invention can accurately and effectively identify the broken zone in the rock formation, thereby better meeting the requirements of oilfield exploration and development.

Description

technical field [0001] The invention relates to the technical field of petroleum engineering, in particular to a method and a device for determining a broken zone in a rock formation. Background technique [0002] Fracture zones are bands of rock disrupted by haphazard cracks and fissures. Fracture zone data is a special geological body, and its structure is relatively complex. Generally, when the fractured zone is outcropped on the surface, it is easier to identify; but when the fractured zone is located underground, it is difficult to be identified, which causes many potential problems in the exploration and development of oilfields. Specifically, since the composition, thickness, and physical properties of some fracture zones will directly affect the extension mode of artificial fractures and the development of remaining oil, the identification and description of fracture zones has become a scientific and practical problem that needs to be solved urgently. difficult iss...

AI Technical Summary

Problems solved by technology

Among them, the fractured zone logging identification has a high recognition rate for the fractured zone, and can effectively identify open fractures and breccia zones, but the identification accuracy of calcite-filled fractures is not enough

In addition, the seismic identification of the fracture zone can obtain the overall spatial distribution of the fracture zone in the rock formation, but due to the limitation of the resolution of seismic data, it is difficult to identify a single small fracture zone

[0004] On the whole, there is still a lack of an effective method for identifying fractured zones in rock formations, so as to better meet the needs of oilfield exploration and development

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