Japan Geoscience Union Meeting 2018

Presentation information

[EJ] Evening Poster

M (Multidisciplinary and Interdisciplinary) » M-IS Intersection

[M-IS08] Drilling Earth Science

Tue. May 22, 2018 5:15 PM - 6:30 PM Poster Hall (International Exhibition Hall7, Makuhari Messe)

convener:Yasuhiro Yamada(Japan Agency for Marine-Earth Science and Technology (JAMSTEC), R&D Center for Ocean Drilling Science (ODS)), Junichiro Kuroda(Department of Ocean Floor Geoscience, Atmosphere and Ocean Research Institute, the University of Tokyo), Kohtaro Ujiie(筑波大学生命環境系, 共同), Yusuke Suganuma(National institute of Polar Research)

[MIS08-P08] In-situ rock physical properties established from continuous drilling parameters: invaluable datasets to analyse state of drilling and rock strength

Adam Wspanialy1, Saneatsu Saito1, KYAW MOE1, *Yasuhiro Yamada1 (1.Japan Agency for Marine-Earth Science and Technology (JAMSTEC), R&D Center for Ocean Drilling Science (ODS))

Keywords:Rock Strength, Specific Energy, Equivalent Strength, Drilling Torque

Surface drilling parameters are excellent datasets to understand in-situ physical properties of the rock. We here present some results from land-based drilling experiments at Atsugi and Boso, Japan. We have acquired large surface drilling datasets together with approximately 100 m of continuous cores. Methods such as Specific Energy (SE) and Equivalent Strength (EST) have been used here to analyse drilling process and physical characteristic of the rock. Results from subsequent core scratching experiments enabled very good correlation and validation of the calculated SE/EST with the measured Unconfined Compressive Strength (UCS). Our field results also demonstrate that the calculated SE/EST successfully detect fractures in the formation, show developing drilling dysfunctions such as vibration, and bit balling. The results also indicate that the frequency and amplitude of the SE/EST oscillations may be used in detecting lithological changes of the drilled rock medium.