10:15 AM - 10:30 AM
[MIS16-06] Relationship between the length of drilled core and the depth of drilled hole – Examples from IODP Exp. 346 U1425 and U1427
Keywords:core-log integration, sediment physical property, IODP Expedition 346
For this purpose, physical property data acquired from both core and logs are compared both in terms of value and data pattern, and natural gamma-ray radiation (NGR), density, and resistivity are commonly used. Generally speaking, higher the vertical resolution of data acquisition is, more precise the quality of correlation is. In the case of IODP Exp. 346, resolutions of shipboard data collection from cores were 0.5 cm for RGB of digital image, 1-5 cm for reflectance spectrum, 2.5-5 cm for gamma-ray attenuation (GRA) density, and 20 cm for NGR, while data acquisition intervals for logging were 0.25 cm for formation micro-scanner (FMS) and 4-15 cm for NGR and density.
Popular correlation method using NGR could enable us the meter-scale pattern matching between the profiles obtained from core onboard and from borehole by logging. Therefore, once we aim to realize higher resolution correlation and integration of core and logging data, we need to utilize FMS data, which vertical resolution is about 5 mm in soft sediments. Because FMS gives a high-resolution relative resistivity profile of the formation, these data should be ideally compared to resistivity measured on whole-round cores at cm-scale interval. However, such data have not been acquired during IODP Exp. 346. In this particular presentation, we will seek for another possibility to implement centimeter-scale correlation between core and logging data.