Method for determining and building bound water for crack-pore (hole) type reservoir core

Abstract

The invention relates to a method for determining and building bound water for a crack-pore (hole) type reservoir core. The method sequentially comprises the following steps of: (1) selecting a crack-free reservoir core; (2) preparing formation water and simulated oil; (3) cleaning and emptying the core, saturating the formation water, driving water by dry gas or the simulation oil until the water does not come out, and thus obtaining the saturation degree of the bound water of a basic rock; (4) perforating the core; (5) calculating the saturation degree of the bound water of the crack-pore (hole) type reservoir core; (6) putting the core into a clamp, and quantitatively saturating bound water for the core; (7) heating the clamp under negative pressure until the system temperature is 120 DEG C, so that the water becomes steam and uniformly distributed; and (8) opening an inlet of the clamp, injecting the simulated oil or the dry gas for displacement, recording a water drainage amount,and thus obtaining the actual saturation degree of the bound water of the core. According to the method, the principle is reliable, the operation is easy, and a reliable physical simulation basis is supplied to a seepage experiment of a crack-pore (hole) type reservoir.

Description

Technical field [0001] The invention relates to a method for determining and establishing irreducible water in seepage experiments of fracture-pore (hole) type sandstone or carbonate reservoirs in the field of petroleum and natural gas exploration and development. Background technique [0002] The seepage test is an important basic test in the development of oil and gas fields. The standard seepage test method only involves homogeneous sandstone reservoirs, and does not consider carbonate or sandstone reservoirs with fractures. Due to the existence of fractures, the irreducible water cannot be accurately determined in such reservoirs. In the process of setting up irreducible water by using conventional methods to evacuate to saturate the water first and then drive water with reservoir fluid, due to the existence of fractures, the irreducible water cannot reach the required value. Therefore, the method of determining and establishing the irreducible water in the fracture-pore...

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Problems solved by technology

[0002] The seepage test is an important basic test in the development of oil and gas fields. The standard seepage test method only involves homogeneous sandstone reservoirs, and does not consider carbonate or sandstone reservoirs with fractures. Due to the existence of fractures, the irreducible water cannot be accurately determined in such reservoirs. In the process of setting up the irreducible water by using the conventional method to evacuate to saturate the water first and then use the reservoir fluid to flood the water, the irreducible water cannot reach the required value due to the existence of fractures. During the seepage experiment, the irreducible water is much higher Therefore, the method of determining and establishing the irreducible water in the fracture-pore (cavity) reservoir core provides a more reliable physical simulation for this kind of reservoir seepage experiment.

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