JUDGE Project: A Continental Scientific Drilling into Subduction Zone (3) Scientific Rationale of the JUDGE Project

摘要

The most challenging topics in earth sciences include mechanism of sediment accretion, stress/strain distribution over decollement zone, deformation/metamorphism of plates and crusts, generation of inter-plate earthquake, genesis of hydrocarbon, and deep fluid circulation all occur in a major scale along the subduction zones. Most of the world's subduction zone is too deep to intersect by drilling from land-based drill sites, if we take the present level of the technology into account. However, there exists exception south of Tokyo metropolitan area where we can reach the upper surface of subducting Philippine Sea (PHS) Plate at a depth of 10 km. The JUDGE hole will penetrate through accretionary wedge and decollement zone before it reaches the PHS plate - The hole will also intersect seismic fault of devastating 1923 Kanto Earthquake and other giant inter-plate earthquakes. Many interesting questions arise about the nature and the role of the dehydrated fluid on the processes of deformation and earthquake generation - These questions can be answered through monitoring and observation using JUDGE hole since it is unparalleled by any other means in earth science.