Intelligent geophysical data acquisition system and acquisition method for shale oil and gas optical fiber

An intelligent geophysical data acquisition system for shale oil and gas optical fiber, comprising a metal casing (1), wherein a pipe string (6) is arranged in the metal casing (1), and an external armored optical cable (2) is fixed outside the metal casing (1):

• an internal armored optical cable (22) is fixed outside the pipe string (6);
• the external armored optical cable (2) comprises a downhole acoustic sensing optical cable (10), two multi-mode optical fibers (11), a strain optical cable (12) and a pressure sensor array (13);
• further comprising horizontal ground acoustic sensing optical cables (14) arranged in the shallow part of the ground according to an orthogonal grid, and artificial seismic source excitation points (7) arranged on the ground according to the orthogonal grid;
• further comprising a composite modulation and demodulation instrument (5) placed near a wellhead;
• six DAS signal ports of the composite modulation and demodulation instrument (5) are connected with the external downhole acoustic sensing optical cable (10) and the ground acoustic sensing optical cables (14) respectively;
• two DTS signal ports of the composite modulation and demodulation instrument (5) are connected with two downhole multi-mode optical fibers (11);
• a DSS signal input port of the composite modulation and demodulation instrument (5) is connected with a head end of the strain optical cable (12);
• and a DPS signal input port of the composite modulation and demodulation instrument (5) is connected with a head end of the pressure sensor array (13);
• the pipe string (6) is a continuous oil pipe or a continuous gas pipe;
• the downhole acoustic sensing optical cable (10) is a high-temperature resistant and high-sensitivity acoustic sensing optical cable;
• the multi-mode optical fibers (11) are high-temperature resistant and high-sensitivity multi-mode optical fibers;
• the strain optical cable (12) is a high-temperature resistant and high-sensitivity strain, optical cable;
• the pressure sensor array (13) is a high-temperature resistant and high-sensitivity pressure sensor array;
• the ground acoustic sensing optical cables (14) are high-sensitivity three-component seismic elastomer acoustic sensitizing sensing optical cables;
• the composite modulation and demodulation instrument (5) is a DAS/DTS/DSS/DPS composite modulation and demodulation instrument.