Three-dimensional electrical resistivity tomography method and system

A system for implementing a three-dimensional electrical resistivity tomography, comprising:

• a two-dimensional resistivity data acquisition module, configured to prospect a region containing a geological anomaly with at least two prospecting modes respectively to acquire cross-hole resistivity detection data and detection surface ERT data, carrying out on the cross-hole resistivity detection data and the detection surface ERT data by geophysical inversion, take the cross-hole resistivity detection data and the detection surface ERT data as a forward basis and adjust model parameters continuously to make a model response to respond to the cross-hole resistivity detection data and the detection surface ERT data, and acquire two-dimensional resistivity data of a corresponding detection plane;
• a same coordinate data point extraction module, configured to unify coordinate systems of resistivity data points acquired in all prospecting modes and extract data points with the same coordinates;
• a data fusion module, configured to carry out data fusion on extracted resistivity data at the same position by utilizing a principal component analysis method;
• and
• a three-dimensional conversion module, configured to carry out three-dimensional coordinate conversion on resistivity data acquired after fusion to form a three-dimensional model having obvious distinction of anomaly boundaries and without pseudo anomaly interference;
• wherein the at least two prospecting modes comprise a surface ERT prospecting mode and a cross-hole resistivity CT prospecting mode;
• wherein the cross-hole resistivity prospecting mode comprises drilling a specified position, arranging a transmitting electrode and a receiving electrode respectively in a transmitting hole and a receiving hole according to a certain electrode distance, electrifying the transmitting electrode and the receiving electrode, and acquiring the cross-hole resistivity detection data;
• wherein the surface ERT prospecting mode comprises arranging surface electrodes on a ground survey line, using a program-controlled electrode change-over switch and a microcomputer engineering electrical surveying instrument to acquire the detection surface ERT data.

A device for implementing a three-dimensional electrical resistivity tomography, comprising:

• a non-transitory computer-readable medium, storing a computer program;
• and
• a processor executing the computer program stored in the medium,
• wherein when executed by the processor, the computer program causes the device to:
• prospect a region containing a geological anomaly with at least two prospecting modes respectively to acquire cross-hole resistivity detection data and detection surface ERT data, carrying out on the cross-hole resistivity detection data and the detection surface ERT data by geophysical inversion, take the cross-hole resistivity detection data and the detection surface ERT data as a forward basis and adjust model parameters continuously to make a model response to respond to the cross-hole resistivity detection data and the detection surface ERT data, and acquire two-dimensional resistivity data of a corresponding detection plane;
• unify coordinate systems of resistivity data points acquired in all prospecting modes, and extracting data points with the same coordinates;
• carry out a data fusion on extracted resistivity data at the same position by utilizing a principal component analysis method;
• and
• carry out a three-dimensional coordinate conversion on resistivity data acquired after fusion to form a three-dimensional model having obvious distinction of anomaly boundaries and without pseudo anomaly interference;
• wherein the at least two prospecting modes comprise a surface ERT prospecting mode and a cross-hole resistivity CT prospecting mode;
• wherein the cross-hole resistivity prospecting mode comprises drilling a specified position, arranging a transmitting electrode and a receiving electrode respectively in a transmitting hole and a receiving hole according to a certain electrode distance, electrifying the transmitting electrode and the receiving electrode, and acquiring the cross-hole resistivity detection data;
• wherein the surface ERT prospecting mode comprises arranging surface electrodes on a ground survey line, using a program-controlled electrode change-over switch and a microcomputer engineering electrical surveying instrument to acquire the detection surface ERT data.