Recently, at the meeting on achievement report of national S&T programs held by the Department of Science and Technology & International Cooperation of the Ministry of Land and Resources, the achievements of the Engineering Development of 3D Great Depth Electromagnetic Survey Project undertaken by the Institute of Geophysical and Geochemical Exploration in 2013 and the first half of 2014 were highly spoken of by the present academicians and experts.  

Since the project began,progress has been made in terms of research on 3D electromagnetic survey methods, development of the key technology and industrialization process of instruments, research on data interpretation and software development,and testapplication. In 2013 and early 2014, furtherheadway was made in the development of key instrument technology and industrialized manufacturing, which signifies an important step towards engineering of key instruments. 

As for research on 3D electromagnetic survey,the Institute conducted research on 3D electromagnetic observation technique according to characteristics of natural electromagnetic field and artificial electromagnetic field, including multi-point measurement technique for natural electromagnetic field and multipole emission/multi-point measurement technique for artificial electromagnetic field, and conducted field experiment of some techniques, providing basis for 3D survey.

As for research on the key instrument technology and industrialized production, 30 kW high-power electromagnetic emission system and 5 kW medium-power emission system are ready to be used, and 160 kW super-power electromagnetic emission system prototype is under development. For development of the receiving system, field test of broadband multifunction electrical receiver shows that the frequency range expands greatly and the background noise reduces greatly,and its noise index is one order of magnitude lower than that of the original receiver. Using the chopper stabilization technique in LF frequency band, the stability index increases by one order of magnitude than that of original receiver.Pilot production of the HF inductive magnetic sensor and field comparison test results show that the frequency response range and sensitivity are up to or beyond the design requirements and thus batch industrial production and application re possible.The Institute developed the TEM three-component receiver and high-power transmitter prototype, three-component time-domain inductive magnetic sensor prototype,and developedthe high temperature superconducting magnetometer. 

As for research on data processing and interpretation method and software development,relevant technical documents were compiled, such as Technical Requirements on Large Scale Development of 3D Great Depth Electromagnetic Survey Software,Outline Design of Integrated Development of 3D Electromagnetic Survey Systems Software,and Module Design Specification of Integrated Development of 3D Electromagnetic Survey Systems Software, to control the software development process.Data examples of typical trial calculation models were formed to ensure that the system runs correctly. The software runs on the electromagnetic data processing and interpretation system of Microsoft Windows 7 (64 bit) and adaptive testing was conducted by a system formed by a theoretical earth electricity model and measured data, getting ready for data processing and interpretation of the first period field test work.

As for application demonstration,the Institute chosean area to conduct test forthe 3D electromagnetic survey instrument,analyzed data of the research area,and put forward geophysical prospecting methods for three minerals, getting ready for 3D electromagnetic survey technique demonstration and application in the second half of 2014.
　　　

In addition, 13 papers (1 SCI paper, 5 EI papers) on the project have been published.Two innovation patents have been awarded and the Institute has applied for four more parents including 3 invention patents.