Three-dimensional high-resolution images of density distributions were obtained on unsplit cores using a medical X-ray computed tomography (CT) scanner. The resolution of CT scanning is about 0.6 mm2 and allows a 5-mm depth for beam width. Electrical resistivity measurements were also conducted to know porosity at high depth resolution after core splitting. Wholeround core samples for this stud...

This paper reviews existing studies and investigates thermal operational regimes of diamond bit during drilling operations. The operating temperature of the diamond core drill is studied under bench condition and an optimal thermal range are presented. Based on this study, it was noted that glazing of diamond tools is observed at temperatures less than 327°C, and normal wear of diamond tools is...

In this study, we report measurements of CFC12 (CCl2F2) in firn air and in air extracted from shallow ice cores from three Antarctic sites. The firn air data are consistent with the known atmospheric history of CFC-12. In contrast, some of the ice core samples collected near the firn-ice transition exhibit anomalously high CFC-12 levels. Together, the ice core and firn air data provide evidence...

Abstract The rock uniaxial compressive strength (UCS) is the basic parameter for support designs in underground engineering. In particular, UCS should be obtained rapidly engineering with complex geological conditions, such as soft rock, fracture areas, and high stress, to adjust excavation plan ensure construction safety. To solve problem of obtaining real-time at sites, a forecast idea propos...

Thanks to the precise core dating and the high sedimentation rate of the drilling site (Gallipoli Terrace, Ionian Sea) we were able to measure a foraminiferal δ(18)O series covering the last 2,200 years with a time resolution shorter than 4 years. In order to support the quality of this data-set we link the δ(18)O values measured in the foraminifera shells to temperature and salinity measuremen...

Otoliths are calcified structures in the head of fish that record environmental information about fish's life history. Gathering the elemental information from the core of an otolith corresponding to the juvenile period of fish's life is critical to discriminate the adult fish to their natal habitats reliably. A high resolution micromill has been used to isolate the otolith core from a whole ot...