论文部分内容阅读
Zenisu deep-sea channel originated from avolcanic arc region, Izu-Ogasawara Island Arc, and vanishedin the Shikoku Basin of the Philippine Sea. According to theswath bathymetry, the deep-sea channel can be divided intothree segments. They are Zenisu canyon, E-W fan channeland trough-axis channel. A lot of volcanic detritus were de-posited in the Zenisu Trough via the deep-sea channel be-cause it originated from volcanic arc settings. On the basis ofthe swath bathymetry, submersible and seismic reflectiondata, the deposits are characterized by turbidite and debritedeposits as those in the other major deep-sea channels. Ero-sion or few sediments were observed in the Zenisu canyon,whereas a lot of turbidites and debrites occurred in the E-Wchannel and trough axis channel. Cold seep communities,active fault and fluid flow were discovered along the lowerslope of the Zenisu Ridge. Vertical sedimentary sequences inthe Zenisu Trough consist of the four post-rift sequence unitsof the Shikoku Basin, among which Units A and B are twoturbidite units. The development of Zenisu canyon is con-trolled by the N-S shear fault, the E-W fan channel is relatedto the E-W shear fault, and the trough-axis channel is relatedto the subsidence of central basin.
Zenisu deep-sea channel originated from avolcanic arc region, Izu-Ogasawara Island Arc, and vanishedin the Shikoku Basin of the Philippine Sea. According to the bathathmetry, the deep-sea channel can be divided intothree segments. They are Zenisu canyon, EW fan A lot of volcanic detritus were de-posited in the Zenisu Trough via the deep-sea channel be-cause it originated from volcanic arc settings. On the basis of the swath bathymetry, submersible and seismic reflection data, the deposits are characterized by turbidite and debritedeposits as those in the other major deep-sea channels. Ero-sion or fewer sedi were were observed in the Zenisu canyon, an a lot of turbidites and debrites occurred in the E-Wchannel and trough axis channel. Cold seep communities , active fault and fluid flow were discovered along the lowerslope of the Zenisu Ridge. Vertical sedimentary sequences inthe Zenisu Trough consist of the four post-rift sequence units of the Shikoku Ba sin, among which Units A and B are twoturbidite units. The development of Zenisu canyon is con-trolled by the NS shear fault, the EW fan channel is related to the EW shear fault, and the trough-axis channel is related to the subsidence of central basin.