Research Of Deep-sea Towed TEM Detection Technology

There are many valuable resources in ocean, it accounts for about70%of earth’s surface, so the exploration of seabed resource determines the human’s survival and development. The features of Electromagnetic method used in Deep-sea is effective, environmental protection, rapid and simple.This paper uses the deep-sea towed TEM,realized the deep-sea exploration that at most4,000meters below sea level.According the actual situation, it establishs a proper model,and after theoretic analysis, confirms the system parameters, builds detection devices, after the reasonable test, it shows that this method is feasible and effective.The main contents of this paper is as follows:1.This paper tells the working principle and development present situation in domestic country and abroad of TEM. According the theory, it puts forward the coincident-loop device and dual polarity rectangle wave.After analysi sing the detection environment, it puts forward a model of two conductive-half-space about seawater and undersea. It derives the calculation formula about Induced voltage of receive coil and apparent resistivity in late-stage.2. This paper designs the parameters, unit of launch and collection, and the unit of remote transmission about deep-sea towed TEM detection system. The launch unit uses intelligent power module of6MBP100RA060and its peripheral circuit. The collection unit uses PCI-4474, made by NI. It uses STM32to control the system, and uses EPIA-M700to store and transmit the data.3.This paper writes the monitoring software under QT environment and QWT plugin. It can draw real-time curves, display and storage data. It designs subroutines of STM32an the software of PC, realized the data processing, data storage, data calculation, data forwarding, data communication, data collection and so on.Debugging process in the experiment contains some steps as follow: partial and the whole debugging in the laboratory, the towed test in sea. Results show that the deep-sea towed TEM detection system and its peripherals can work normally.