10.1594/PANGAEA.776096
O'Regan, Matthew
Matthew
O'Regan
Tie points and log-adjusted depth scales for ODP Leg 207 Sites
PANGAEA
2007
Composite Core
Drilling/drill rig
Leg207
Joides Resolution
Ocean Drilling Program (ODP)
2003-01-22T00:00:00/2003-10-28T10:10:00
en
Supplementary Publication Series of Datasets
10.2973/odp.proc.sr.207.113.2007
4 datasets
application/zip
Creative Commons Attribution 3.0 Unported
Multiple copies of Cretaceous black shales extending from the early Cenomanian to the end of the Santonian were recovered at five sites on Demerara Rise during Leg 207 of the Ocean Drilling Program. These sediments are primarily composed of laminated organic-rich claystones interbedded with coarser, lightly laminated foraminferal-bearing packstones and wackestones. The black shales represent the local expression of widespread organic-rich sedimentation in the Atlantic during the mid-Cretaceous. However, incomplete recovery prevented construction of continuous composite sections, resulting in uncertainties concerning the correct stratigraphic placement of individual cores. By combining high-resolution measurements of bulk density collected shipboard on the multisensor track with continuous downhole measurements of formation resistivity using the Formation MicroScanner, an equivalent logging depth scale was constructed for black shales recovered from Sites 1258, 1260, and 1261. The integrated depths approach centimeter-scale resolution and are supported by comparisons of coarser resolution natural gamma ray emissions collected on cores and through downhole logging operations. The new depths highlight the extent of both intra- and intercore gaps and provide an opportunity to further constrain temporal and spatial paleoceanographic changes captured in proxy records from these sediments.
Supplement to: O'Regan, Matthew (2007): Data report: Log-adjusted depth scales for Cretaceous black shale deposits from Demerara Rise. In: Mosher, DC; Erbacher, J; Malone, MJ (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 207, 1-29
-54.73331
-54.3173
9.04861
9.43333333333333
South Atlantic Ocean
Walvis Ridge, Southeast Atlantic Ocean