Description: Total carbon measurement (LECO CS744 elemental analyser, Bremen University). The analyses were performed by heating 0.1 g of homogenised material in a ceramic dish and measuring the resulting CO2 in IR cells. The carbonate content has been calculated as the difference between the total carbon content and the organic carbon content, measured in a second sample that was pre-treated with hydrochloric acid to remove carbonates. Both measurements have an accuracy of 0.001 mg (1 ppm) or 0.5 % relative standard deviation (RSD). The inorganic carbon was then converted to carbonate content using the molecular mass of calcium carbonate. The carbonate content data were combined with dry bulk density (DBD) and sedimentation rate (SR, this study) to calculate the carbonate accumulation rate (CaCO3 AR) as CaCO3 AR = (CaCO3 % / 100) x DBD x SR for the four time intervals MIS 5, MIS 9, MIS KM5 and MCO for the Leg 154, Site 927, Ceara Rise, tropical Atlantic Ocean. The composite depths and age model presented are from this study.

Description: 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.