Research On A Scalable Geophysieal Data Acquisition System

It is urgently needed and necessary to conduct in-depth and detailed geo-physical exploration because on the one hand the geophysical exploration can help people grasp the distribution of underground mineral resources, on the other hand, it can help us know some geological disasters in advance.Today’s large-scale geophysical data acquisition system has the develop-ment trend of wider exploration range and higher sampling channel density. The improvement of the density of sampling channel improves the SNR and fidelity in geophysical exploration. However, in traditional large-scale geophysical data acquisition systems, the performance of data center becomes the bottleneck of sys-tem expansion because of too much connection between acquisition station and data center. Based on the analysis of the requirement when conducting sampling channel expansion, this passage proposed a kind of large-scale geophysical data acquisition system which has distributed management capabilities, distributed storage capacity and distributed timing capabilities. These characteristics give the system high reliability, flexibility as well as good sampling channel expansion ability.In this kind of scalable large-scale geophysical data acquisition system, the power station has distributed management capabilities, distributed storage capac-ity and distributed timing capabilities in addition to simple power management ability. So the power station provides the acquisition station with all the needed working conditions. Packing these two stations together will achieve the new base unit for this new system. This new base unit does not rely on the data center. So when conducting system expansion, the managing capabilities, storage capacity and timing capabilities of the system will increase accordingly, making the sys-tem has good scalability, reliability and flexibility The thesis is divided into the following five chapters:The first chapter is an introduction to the development trend of sampling channels extension of the large-scale geophysical data acquisition system. It ex-plains the reason why the number of sampling channels is affected by the perfor-mance of data center. A kind of scalable large-scale geophysical data acquisition system is designed. It can provide sampling data with high signal to noise ra-tio and high fidelity, thereby enhancing the probing depth and resolution in the exploration.The second chapter describes the design ideas used in the design process of the acquisition system and the way to achieve the sampling channel extension. The concept of domain is put forward according to the distribution of sampling channels in the exploration area. By giving the system a distributed management capabilities, distributed storage capacity and distributed time service capabilities, each domain of the system can complete the work of data acquisition indepen-dently. So that the data center orients the entire system, making the number of sampling channels being no longer constrained by data center performance any more.The third chapter elaborates the implementation of cables and other specific hardware in the prototype of scalable geophysical data acquisition systems. It explains the structures of each station and the definitions and application of the interface of each part. It also elaborates the process of data transmission, clock synchronization and the design of the power station.The fourth chapter describes the implemented function of the acquisition system and make a preliminary test to the precision of distributed synchronous clock source. The test results are analyzedFinally, The thesis is summarized and makes recommendations for improve-ment.