The Deep-sea Drilling Vessel Chikyu Test Drilling off the Shimokita Peninsula
- Damaged conditions on BOP Hydraulic Connectors-

    The Deep-sea Drilling Vessel Chikyu of Japan Agency for Marine-Earth Science and Technology (JAMSTEC; Yasuhiro Kato, President) had started to raise Riser pipes from the sea on October 12 and after hauled the upper part of BOP on the ship in the morning on October 15, evaluated the damaged condition of BOP Hydraulic Connectors that seemed to be caused by severe welters affected by the rapidly developed low-pressure, at the test drilling area off the Shimokita Peninsula (100 kilo meters north east off Hachinohe City). (Appendix 1)
    One of Cylinders (rod-like part) had been found bended, that located one of two Hydraulic Connectors in upper BOP for pumping those connectors up and down. (Appendix2,3)
    Right now, we are arranging the replacement part but it's difficult to obtain promptly. A safe riser drilling can not be done without this replacement. And evaluation of damaged condition for lower part of BOP need to be done, which remains installed to the sea floor.
    On the other hand, System Integration Tests (SIT)* that is the main purpose of this test drilling had already been conducted; as for the remaining test items, it's expected to be conducted during the test period.
    In off the Shimokita Peninsula, usually, severe weather continues after November, so that we planned conducting the test drilling by the month of October from the beginning. From those reasons it is judged that continuing drilling is very difficult. Therefore, we announce that the Test Drilling off the Shimokita Peninsula is going to be completed this time.
    Now, we are planning to reattach BOP and restore the drilled borehole, and then pull up the whole BOP and Riser pipes to evaluate the damaged conditions.

*System Integration Tests (SIT)
1. Running the riser and blow-out preventer (BOP)
2. Testing the emergency disconnect sequence (EDS) for the riser and BOP
3. Inserting the casing pipe and cementing
4. Test operation of the Chikyu's three core sampling systems
5. Testing the wireline logging system (which measures formation properties.)