過去世界上研究地震預測，常存在兩個關鍵致命傷，其一是大震的罕發性，其二是儀器的覆蓋密度低。台灣乃一蕞爾小島，是幸也不幸有頻繁的地震，這樣的先天條件下，如果我們可以建置起緊密的大地電磁觀測網，那麼很多地震電磁現象，不論是前兆或震後現象都極有可能在台灣被徹底觀測，乃至於最終推向預測之可能性。本計畫旨在從理論、實驗與觀測三個角度，論證斷層帶是否有條件在大震之前產生巨大的極化電荷與電場。我們希望建立起全島的長期大地電場監測網，以接收地球上天然電磁波擾動之寬頻帶電磁資料，頻率範圍從數百至數萬分之ㄧ赫茲，對應於由淺至深的震源介質電性變化。我們也會從岩石力學實驗與有效介質理論，探討岩石宏觀破裂前的極化電場存在之條件，以期釐清地震電磁現象在預測上的可行性。從國際固體地球科學的角度看台灣在地震學的地位與重要性，乃在於台灣有極好的地震資料。之所以具備這些國際同儕渴求的優質資料，主要原因則是因台灣有密度屬全球第一的極佳地震觀測網。頻震復加地小，我們期望有機會為台灣再造一個全球研究地震預測的獨特角色，更進一步提升台灣在國際地球科學社群之地位。 There are two fatal limitations for the past studies of earthquake precursors -- the rarity of great earthquakes and the low coverage of instrumental observatories. Taiwan is a small island located at the western Pacific Ocean. It is the good fortune that we have unfortunately frequent seismicity. So that, if we can construct a dense network of electromagnetic monitoring stations a lot of earthquake-induced electromagnetic phenomena, no matter precursory or co-seismic ones, will be eventually observed throughout Taiwan. This then leads to a good possibility of earthquake prediction. This project aims at arguing, based on three viewpoints of theory, experiments and field-observations, the conditions of producing the electrical polarization charges and the electric field prior to a great earthquake of a shear zone. We will set up the long-term monitoring net of electrical fields throughout the island, to record the wide-band data of the electrical fields with the frequency range from 100 to 10-4 Hz which can image hypocentral materials at various depths from few to several ten kilometers. Based on both laboratory experiments and effective medium theory of rock mechanics, we will also probe into the possibility of electrical polarization field existing before macroscopic breakdown of rocks, which might help us to elucidate the prediction feasibility of electromagnetic phenomena. Having high quality data of seismology, which is actually a consequence of the densest seismological network equipped, makes Taiwan a unique and important position in the solid earth discipline around the world. Now, frequent earthquakes and small territory are giving us another opportunity to be unique in the role of earthquake prediction among the international Earth Science community, by means of equipping Taiwan a dense observatory network of monitoring natural electrical fields. 研究期間：10008 ~ 10107
