Hybrid transponder system for long-range sensing and 3D localization

A system to determine a size, extent, and orientation of a hydraulic fracture of a reservoir, the system comprising:

• a plurality of transponders configured to be carried by a fluid into a hydraulic fracture of a reservoir to deploy the plurality of transponders within the reservoir, each transponder of the plurality of transponders comprising a substrate carrying:
• a radiofrequency (RF) receiver antenna configured to receive RF signals,
• a digital control circuit, and
• an acoustic transmitter configured to transmit an acoustic return signal, the acoustic transmitter including a thermo-acoustic device configured to be activated by the digital control circuit to heat an environmental fluid in contact with the transponder while the transponder is deployed within the reservoir to generate a pressure wave defining the acoustic return signal;
• and
• a reader dimensioned to be deployed within a wellbore, the reader comprising:
• an RF antenna assembly including an RF antenna,
• an RF transmitter operably coupled to the RF antenna and configured to transmit an RF signal to each transponder of the plurality of transponders deployed within the reservoir, and
• an acoustic receiver configured to receive acoustic return signals from the plurality of transponders deployed within the reservoir, the acoustic return signals comprising the pressure waves generated as a result of the heating of the environmental fluid in contact with the plurality of transponders and the acoustic return signals configured to be processed to determine characteristics of the hydraulic fracture.