Crack distribution detection method based on rock resistance change

Abstract

The invention discloses a crack distribution detection method based on rock resistance change. The method comprises the following detection steps: rock sample surface treatment operation, rock samplecrack wetting operation, rock sample surface copper sheet embedding operation, temperature sensor and external equipment connection operation, rock sample induced polarization treatment, analysis of the temperature change condition of a temperature map, and construction of a rock sample internal crack distribution geometric model. The invention relates to the induced polarization property of rock.Water vapor is pumped into the rock to realize wetting of rock cracks, copper sheets are mounted at two ends of the rock to realize electrification of the rock, and a temperature sensor is applied torealize measurement of a rock temperature map. The resistivity of the rock entity is different from that of the crack, the same induced polarization current is introduced, the temperature of the rockentity is different from that of the crack, and the change of the temperature map can reflect the crack distribution. The initial form of rock cracks is not damaged during detection, the detection cost is low, the efficiency is high, corollary equipment is simple, and the accuracy is good.

Description

technical field [0001] The invention belongs to the field of rock crack detection in petroleum and natural gas engineering, and in particular relates to a crack distribution detection method based on rock resistance change. Background technique [0002] The detection of rock crack morphology and crack parameters is of great significance in the research of drilling rock fracture and hydraulic fracturing stimulation. In the oil and gas industry, traditional rock crack detection methods mainly include mercury intrusion method, scanning electron microscope imaging method, acoustic wave or seismic wave detection method, etc. Mercury porosimetry is a method that relies on external pressure to force mercury to overcome surface tension and enter rock cracks to determine its crack structure and distribution. As the external pressure increases, the mercury can enter smaller pores, and the more mercury will enter the rock cracks. However, the mercury intrusion method requires that th...

AI Technical Summary

Problems solved by technology

The interaction between secondary electrons and the surface of the sample will generate a series of signals such as secondary electrons, backscattered electrons, European leather electrons, and X-rays, which pass through different detectors such as secondary electron detectors, X-ray energy spectrum analyzers, etc. To distinguish these signals to obtain the distribution characteristics of the sample surface, but the scanning electron microscope imaging method cannot conduct an in-depth study of the internal cracks of the rock

[0004] (1) The integrity of the crack is low, and the degree of damage to the rock is relatively large;

[0005] (2) The detection of internal cracks is not ideal, and the internal cracks of the rock cannot be detected effectively;

[0006] (3) The detectable rock type has high limitations, and the influence of the internal properties of the rock needs to be overcome;

[0007] (4) The experimental principle is complicated, the experimental cost is expensive, the detection efficiency is low, and the phenomenon is not intuitive and clear

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