Mid-Cretaceous Sierra Madre Oriental Carbon Isotope Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!! NAME OF DATA SET: Mid-Cretaceous Sierra Madre Oriental Carbon Isotope Data LAST UPDATE: 11/2003 (Original Receipt by WDC Paleo) CONTRIBUTOR: Tim Bralower, University of North Carolina (Now at Pennsylvania State University) IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2003-079 SUGGESTED DATA CITATION: Bralower, T.J, et al., 2003, Mid-Cretaceous Sierra Madre Oriental Carbon Isotope Data, IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2003-079. NOAA/NGDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Bralower, T.J., E. CoBabe, B. Bradford Clement, W.V. Sliter, C.L. Osburn, and J. Longoria, 1999, The record of global change in mid-Cretaceous (Barremian-Albian) sections from the Sierra Madre, northeastern Mexico. In Huber, B.T., T.J. Bralower, and R.M. Leckie, A memorial volume to William V. Sliter, Journal of Foraminiferal Research, v. 29, 4, p. 418-437. GEOGRAPHIC REGION: Northeastern Mexico PERIOD OF RECORD: Mid-Cretaceous (Barremian to Albian) DESCRIPTION: Mid-Cretaceous (Barremian to Albian) carbon cycle data from hemipelagic sediments deposited along the continental margin of northeastern Mexico. Data consist of dC13 analyses of organic matter and Corg and CaCO3 analyses by coulometry. Samples were collected from 4 sections in the Sierra Madre Oriental (~25-25.2N, ~100-100.7W) along a transect from pelagic (La Boca Canyon) to hemipelagic (Canyon Los Chorros) ABSTRACT: Our current understanding of mid-Cretaceous global change is largely based on investigations of pelagic sections in southern Europe and deep sea drilling sites. Much less information exists from other continents and from sections deposited on continental margins. This investigation seeks to broaden our understanding of mid-Cretaceous global change by focusing on the record from sections deposited along the continental margin of northeastern Mexico. The major goals are to compare the record, timing, and extent of the Oceanic Anoxic Events (OAEs) in Mexico and other areas, and to determine the relationship between these events and the global burial of organic material using carbon isotope stratigraphy. We have investigated four sections from the Sierra Madre Oriental, integrating biostratigraphy, magnetostratigraphy and carbon isotope stratigraphy. Carbon isotopes, measured on the organic carbon (Corg) fraction, show identical stratigraphic changes to curves from Barremian to lower Albian European and Pacific deep-sea sections. Our results add new detail to the C-isotope stratigraphy of the middle and late Albian interval. Three abrupt peaks in Corg content correlate with OAE1a (early Aptian), OAE1b (early Albian) and a new event in the late Aptian Globigerinelloides algerianus Zone. All three events correspond to short-term, 0.5-3 per mil decreases in C-isotope values followed by increases of similar magnitude. The decreases may reflect changes in the type of Corg the nature of carbon cycling, or an increase in hydrothermal activity. The increases in C-isotope values reflect widespread burial of Corg. The similar shape of the C-isotope curves in Mexico and other areas, and the response of C-isotopes to the OAEs, indicate that the late Aptian episode was extensive, and that OAE1a and OAE1b were global. The three anoxic events were characterized by different changes in relative sea level. OAE1a corresponds to the early stages of transgression, the late Aptian event correlates to peak flooding, and OAE 1b corresponds to a regressive interval. OAE1a also corresponds to major changes in nannofossil assemblages; the well-known "nannoconid crisis" can be easily recognized in the Mexican sections. This event is characterized by an increase in abundance of nannofossils and foraminifera in sediments, possibly reflecting a decrease in dilution as a result of the rise in relative sea level. DATA: 1. Cienega del Toro section Total Organic Carbon (%), delta13C (per mil) Missing value = -999 Sample avg. TOC delC avg. TS avg. TC avg. AIS CTB95 1 0.14 -23.889 0.93 8.18 0.71 CTB95 1.1 0.10 -999 0.27 9.30 0.23 CTB95 2 0.09 -23.624 0.06 9.74 0.03 CTB95 2.3 0.11 -999 0.47 9.09 0.42 CTB95 3.1 0.07 -24.200 0.05 9.71 0.03 CTB95 4 0.06 -999 0.04 10.36 0.02 CTB95 4.1 0.09 -23.975 0.04 10.54 0.02 CTB95 5 0.08 -999 0.03 10.65 0.01 CTB95 5.5 0.08 -999 0.08 10.63 0.06 CTB95 6 0.09 -999 0.03 10.56 0.01 CTB95 6.1 0.08 -23.713 0.03 10.39 0.02 CTB95 7 0.05 -999 0.04 10.18 0.02 CTB95 7.1 0.08 -24.163 0.11 10.39 0.11 CTB95 8 0.08 -999 0.36 10.54 0.29 CTB95 9 0.06 -24.630 0.18 13.05 0.17 CTB95 9.1 0.07 -999 0.21 12.71 0.20 CTB95 10 0.04 -23.587 0.03 12.30 0.01 CTB95 10.1 0.08 -999 0.06 12.99 0.05 CTB95 11 0.04 -25.700 0.02 12.90 0.01 CTB95 12 0.05 -999 0.02 13.18 0.01 CTB95 12.1 0.11 -24.148 0.10 12.98 0.10 CTB95 13.1 0.13 -999 0.15 12.60 0.12 CTB95 14 0.10 -24.355 0.15 12.82 0.14 CTB95 14.1 0.13 -999 0.30 12.61 0.27 CTB95 15 0.11 -24.450 0.13 12.95 0.11 CTB95 16 0.13 -999 0.07 13.13 0.09 CTB95 16.1 0.08 -24.268 0.11 13.18 0.07 CTB95 17 0.06 -999 0.03 12.79 0.01 CTB95 17.1 0.05 -25.038 0.04 13.14 0.02 CTB95 18.1 0.04 -999 0.02 13.03 0.01 CTB95 18.2 0.05 -25.015 0.02 12.71 0.01 CTB95 19 0.02 -999 0.01 13.02 0.00 CTB95 19.1 0.06 -25.100 0.04 13.11 0.03 CTB95 20 0.06 -999 0.02 13.20 0.01 CTB95 20.1 0.05 -24.313 0.01 13.05 0.01 CTB95 21 0.06 -999 0.03 13.12 0.03 CTB95 22 0.06 -24.962 0.13 13.22 0.12 CTB95 23 0.08 -999 0.02 12.50 0.01 CTB95 23.1 0.09 -23.791 0.01 12.77 0.01 CTB95 24 0.06 -999 0.01 13.03 0.01 CTB95 24.1 0.06 -25.049 0.05 13.12 0.04 CTB95 25 0.06 -999 0.08 12.96 0.07 CTB95 26 0.06 -24.810 0.23 12.91 0.03 CTB95 26.3 0.09 -999 0.04 12.87 0.20 CTB95 27 0.05 -25.457 0.02 12.98 0.01 CTB95 28 0.06 -999 0.02 13.16 0.01 CTB95 28.2 0.28 -24.965 0.02 12.41 0.01 CTB95 29 0.05 -999 0.02 11.79 0.01 CTB95 29.2 0.08 -23.865 0.02 10.22 0.02 CTB95 30 0.05 -999 0.02 12.49 0.01 CTB95 31 0.07 -25.029 0.02 12.73 0.01 CTB95 31.5 0.05 -999 0.02 13.03 0.01 CTB95 32 0.03 -24.008 0.01 13.18 0.00 CTB95 33 0.05 -999 0.02 12.79 0.01 CTB95 34 0.08 -25.124 0.02 13.13 0.01 CTB95 35 0.06 -999 0.02 13.25 0.01 CTB95 36 0.10 -24.995 0.99 13.03 1.06 CTB95 37 0.03 -999 0.02 13.11 0.01 CTB95 38 0.07 -24.997 0.02 12.75 0.01 CTB95 39 0.08 -999 0.03 12.88 0.01 CTB95 40 0.08 -24.997 0.05 12.65 0.01 CTB95 41 0.08 -999 0.05 12.56 0.03 CTB95 42 0.10 -24.968 0.24 12.82 0.22 CTB95 43 0.10 -999 0.02 13.11 0.01 CTB95 44 0.10 -24.899 0.05 13.16 0.04 CTB95 45 0.07 -999 0.02 12.96 0.01 CTB95 46 0.07 -25.010 0.02 13.24 0.01 CTB95 47 0.04 -999 0.03 13.08 0.01 CTB95 48 0.03 -24.605 0.02 13.26 0.01 CTB95 49 0.07 -999 0.02 13.13 0.01 CTB95 50 0.06 -24.779 0.02 12.64 0.01 CTB95 50.11 0.09 -25.344 0.05 11.92 0.03 CTB95 50.14 0.07 -999 0.08 12.71 0.09 CTB95 50.15 0.03 -999 0.02 12.53 0.01 CTB95 50.18 0.06 -25.406 0.07 12.92 0.06 CTB95 50.2 0.06 -999 0.03 13.23 0.03 CTB95 50.3 0.08 -24.099 0.03 12.18 0.01 CTB95 50.5 0.09 -999 0.02 12.40 0.01 CTB95 50.7 0.08 -24.567 0.03 12.14 0.01 CTB95 50.9 0.08 -999 0.03 13.28 0.01 2. La Boca section Total Organic Carbon (%), delta13C (per mil) Missing value = -999 Sample depth avg. TOC del13C avg. TC avg. TS avg. AIS BCA94-57 286.4 0.169 -22.700 9.944 0.096 0.081 BCA94-55 283.8 0.089 -999 9.925 0.107 0.095 BCA94-53 281.9 0.083 -22.087 11.550 0.127 0.069 BCA94-51 279.1 0.141 -999 11.325 0.095 0.092 BCA94-49 276.3 0.160 -22.200 10.860 0.117 0.094 BCA94-47 274 0.116 -21.305 10.990 0.155 0.113 BCA94-45 270 0.173 -23.037 7.251 0.126 0.081 BCA94-43 268.3 0.081 -21.220 10.760 0.120 0.039 BCA94-41 266.4 0.138 -999 9.266 0.098 0.054 BCA94-39 265.3 0.117 -999 10.225 0.113 0.086 BCA94-37 263.6 0.113 -21.833 11.040 0.115 0.068 BCA94-35 261.8 0.160 -999 10.885 0.127 0.095 BCA94-33 260 0.340 -21.608 10.145 0.680 0.409 BCA94-31 257.1 0.319 -999 10.290 0.124 0.089 BCA94-29 255.6 0.083 -21.736 11.550 0.107 0.076 BCA94-27 253.9 0.072 -999 10.885 0.100 0.070 BCA94-25 251.8 0.138 -999 11.165 0.115 0.078 BCA94-23 250.3 0.187 -22.300 9.785 0.107 0.076 BCA94-21 248.5 0.069 -22.131 10.370 0.098 0.064 BCA94-19 245.7 0.133 -999 10.380 0.123 0.074 BCA94-17 243.9 0.103 -999 10.830 0.139 0.098 BCA94-16 242.1 -999 -22.620 -999 -999 -999 BCA94-15.5 241.3 0.215 -21.679 10.255 0.127 0.087 BCA94-14 240.7 0.178 -999 10.980 0.131 0.068 BCA94-12 238.3 0.110 -999 10.325 0.125 0.094 BCA94-10 235.6 0.080 -999 11.140 0.135 0.084 BCA94-8 233 0.123 -23.899 9.867 0.109 0.082 BCA94-6 230.3 0.097 -999 10.275 0.120 0.071 BCA94-4 227.7 0.088 -24.626 11.615 0.106 0.091 BCA94-2 225 0.143 -999 9.921 0.104 0.082 BCA94-1 224 -999 -24.900 -999 -999 -999 BCA94-0 223 0.240 -999 7.525 0.972 0.912 BCA94-(-1) 221.6 -999 -24.994 -999 -999 -999 BCA94(-2) 221 0.080 -999 11.900 0.468 0.067 BCA94(-4) 219.2 0.081 -999 12.260 0.111 0.070 BCA94(-6) 216.4 0.066 -21.613 12.240 0.120 0.077 BCA94(-8) 215.6 0.116 -21.840 12.260 0.101 0.081 BCA94(-10) 213.5 0.053 -22.746 12.295 0.127 0.085 BCA94(-12) 211.8 0.062 -21.744 12.295 0.112 0.059 BCB-39 ** 203.5 0.056 -22.233 11.815 0.099 0.0415 BCB-30 184 0.06 -22.255 12.435 0.104 0.032 BCB-23 165.6 0.056 -22.237 12.005 0.103 0.0485 BCB-19 156.8 0.072 -999 12.055 0.12 0.0345 BCB-18 136.8 0.08 -22.628 12.185 0.12 0.048 BCB-10 121.9 0.052 -22.675 12.350 0.1 0.052 BCB-5 115.5 0.105 -22.383 11.660 0.117 0.049 BCB-1 109.4 0.073 -22.331 12.365 0.134 0.0645 3. Los Chorros section Total Organic Carbon (%), delta13C (per mil) Sample TOC delC TS TC AIS LC1 0.03 -26.7 0.03 10.88 0.01 LC2 0.02 -26.188 0.02 10.92 0.01 LC3 0.07 -25.989 0.02 10.92 0.01 LC5 0.32 -22.065 0.05 10.41 0.02 LC6 0.1 -23.251 0.05 10.18 0.02 LC7 0.08 -23.874 0.07 10.36 0.01 LC7.2 0.07 -22.324 0.06 11.00 0.01 LC7.5 0.25 -25.201 0.06 10.60 0.03 LC8 0.05 -24.834 0.06 10.77 0.01 LC9 0.04 -24.373 0.04 10.59 0.01 LC10 0.03 -23.965 0.03 10.74 0.01 LC11 0.03 -999 0.04 10.82 0.01 LC12 0.04 -23.733 0.04 10.66 0.01 LC44 0.06 -23.784 0.05 10.62 0.01 4. Santa Rosa section Total Organic Carbon (%), delta13C (per mil) SAMPLE DEPTH TOC D13C(CORG) 97 1 0.054 -25.53 98.8 5 0.029 -24.915 101.3 9 0.059 -24.469 104.4 13 0.05 -24.65 108 17 0.033 -999 111.4 21 0.083 -24.908 115.8 25 0.056 -24.725 117 26 0.036 -25.027 117.75 26.5 0.124 -999 119.4 29 0.042 -24.456 122.2 32 0.074 -999 125 34.5 0.155 -999 125.4 35 0.051 -24.845 133.5 37 0.738 -999 133.9 37.5 1.183 -25.083 135.5 39.5 2.512 -25.174 135.9 40 1.573 -999 139.2 43 1.599 -25.523 137.3 41.5 0.412 -24.004 139.6 43.5 1.394 -24.609 141.7 45.5 1.443 -999 142 46 1.894 -23.983 142.2 46.5 1.854 -999 143.3 49 0.348 -23.593 144.1 50.5 0.81 -23.471 144.5 51 0.406 -23.545 145.1 52 0.663 -23.95 146.7 55 0.257 -24.053 147.1 55.5 0.902 -999 148 56.5 1.316 -24.28 148.9 58 0.536 -23.445 149.2 58.5 0.255 -999 150.9 61 0.153 -23.763 152.6 62.5 0.309 -999 153.7 64 0.49 -24.165 155.3 65.5 0.258 -999 156.3 66.5 0.145 -999 156.9 67 0.112 -23.362 158.2 68.5 0.635 -22.992 159.4 69.5 0.253 -999 159.7 70 0.188 -999 160.3 71 0.123 -23.279 162.9 74 0.118 -999 166.9 79 0.09 -23.407 171.2 82.5 0.287 -23.438 171.7 83 0.102 -23.835 176.1 87 0.151 -23.667 181.1 91 0.115 -24.4 183.1 93 0.049 -999 184.4 94 0.04 -24.389 185.4 95 0.068 -24.272 188.1 96 0.035 -24.561 189.8 97 0.056 -24.667 190.5 98 1.798 -999 191.2 99 1.441 -25.693 192.4 100 2.664 -26.094 193.4 101 1.341 -26.163 194.3 102 0.179 -25.347 195.1 103 0.798 -24.588 195.7 104 0.506 -999 196.3 105 0.929 -25.856 196.9 106 1.522 -24.34 197.6 107 0.497 -999 204.4 111 0.073 -23.748 208.3 115 0.052 -24.32 209.8 C1 0.049 -23.68 211.3 C2 0.083 -23.34 212.8 C3 0.245 -24 214.3 C4 0.061 -23.5 215.8 C5 0.09 -23.66 217.3 C6 1.107 -24.59 218.8 C7 0.415 -23.2 220.3 C8 0.615 -25.13 221.05 C8.5 0.115 -999 221.8 C9 0.339 -999 223.3 C10 0.171 -24.97 224.8 C11 0.666 -25.16 225.55 C11.5 1.211 -999 226.3 C12 0.261 -24.9 227.8 C13 1.108 -26.18 229.3 C14 1.107 -25.77 230.8 C15 0.14 -999 232.3 C16 0.054 -24.24 236.8 C19 0.184 -24.1 239.8 C21 0.073 -24.75 241.3 C22 0.071 -24.2 242.8 C23 0.006 -24.4 244.3 C24 0.127 -999 245.8 C25 0.777 -999 247.3 C26 0.087 -25.03 248.8 C27 0.202 -999 250.3 C28 0.147 -999 251.8 C29 0.101 -25 253.3 C30 0.514 -999 254.8 C31 0.092 -24.3 256.3 C32 0.165 -999 257.8 C33 0.046 -25.3 259.3 C34 0.067 -999 260.8 C35 0.05 -999 262.3 C36 0.051 -999 263.8 C37 0.092 -999 265.3 C38 0.074 -999 266.8 C39 0.062 -24.9 269.8 C41 0.032 -24.5 277.3 C46 0.03 -999 281.8 C49 0.034 -24.5 284.8 C51 0.042 -25.32 289.3 C54 0.053 -25.1 292.3 C56 0.09 -24.35 295.3 C58 0.091 -25 299.8 C61 0.072 -26.5 304.3 C64 0.113 -25.4 307.3 C66 0.148 -26.13 308.8 C67 0.19 -25.4 314.8 C71 0.207 -25.78 319.3 C74 0.156 -25.4 322.3 C76 0.13 -25.15 328.3 C80 0.099 -999