| Summary: | Compilation of carbonate content data for the five sites of the Leg 154, Ceara Rise, tropical Atlantic (Initial report, https://doi.org/10.2973/odp.proc.ir.154.1995, Curry et al., 1995, IODP website, https://web.iodp.tamu.edu/OVERVIEW/, last visit: 5 April 2022, King et al., 1997, http://www-odp.tamu.edu/PUBLICATIONS/154_SR/23_CHAP.PDF, http://www-odp.tamu.edu/publications/154_SR/CHAP_23/23_TBL01.TXT, last visit: 5 April 2022, Frenz et al., 2006, https://doi.org/10.1594/PANGAEA.547743, https://doi.org/10.1016/j.margeo.2006.07.006, last visit: 5 April 2022). The composite depths have been revised according to Wilkens et al. (2017, DOI:10.5194/cp-13-779-2017) composite depths. With the dry bulk density (calculated as described below) and sedimentation rate derived from Wilkens et al., (2017, DOI:10.5194/cp-13-779-2017) age model for all the fives sites, the Carbonate accumulation rate (CaCO3 AR) has been calculated as : CaCO3 AR = (CaCO3 % / 100) x DBD x SR. Following the approach by Lyle (2003, DOI:10.1029/2002PA000777), we first derived for each site a calibration between the gamma-ray attenuation (GRA) bulk density and DBD using data from Curry et al. (1995). The resulting site-specific calibrations were then applied on GRA bulk density values, which were extracted from Curry et al. (1995), and interpolated to the position of the analysed samples using linear interpolation. This yielded DBD values between 0.40 g cm-3 and 1.64 g cm-3. For two samples, the calibration returned negative DBD (at 129.62 mcd and 135.47 mcd) due to two anomalous GRA values below 1. In these cases, we used the DBD of the nearest point instead.
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