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SCIENCE CHINA Earth Sciences, Volume 60 , Issue 1 : 30-43(2017) https://doi.org/10.1007/s11430-016-0092-5

Characterization of the negative carbon isotope shift in segment C2, its global implications as a harbinger of OAE1a

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  • ReceivedOct 20, 2016
  • AcceptedNov 7, 2016
  • PublishedDec 14, 2016

Abstract


Acknowledgment

We gratefully acknowledge the support of the Glenn A. Goodfriend Memorial funds for fieldwork and laboratory analyses. Many thanks are due to Diane Pirie for her unwavering help with our carbon analyzer and gracious help at all steps of this research. We thank Bill Anderson for the carbon isotope analyses, and Cesar Ramirez at FIU’s Advanced Mass Spectrometry Facility for the biomarker analyses. Special thanks to Xiumian Hu and his collaborators for graciously hosting the IGCP 609 Workshop in China (September 2015) where we had the opportunity to discuss the ideas presented in this paper. We are most grateful to our colleague Josep Moreno-Bedmar for logistic support during part of the fieldwork, and discussions about ammonites. Mr. Ferran is gratefully acknowledged for his amiable authorization to carry out sampling of the El Pui section on his private hunting property. We also thank two anonymous reviewers for providing detailed comments that helped refine the manuscript. The Earth and Environment Department at FIU generously provided supplies and other laboratory materials. This paper is a contribution of IGCP Project 609 “Climate-environmental deteriorations during greenhouse phases: Causes and consequences of short-term Cretaceous sea-level changes”.


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  • Figure 1

    Panoramic view of El Pui section showing the approximate position of carbon isotope segments C1, C2 and C3 correlative with similar chemostratigraphic segments defined by Menegatti et al. (1998).

  • Figure 2

    Carbon isotope curve comparing the intra-segment C2 negative excursion of four different locations. (a) Djebel Serdj, Tunisia: Modified from Heldt et al. (2008). (b) Comanche Platform, USA: Modified from Phelps et al. (2015). (c) Santa Rosa Canyon, Mexico: Modified from Li et al. (2008). (d) El Pui, Spain: Modified from Sanchez-Hernandez and Maurrasse (2016).

  • Figure 3

    Lithostratigraphy and carbon chemostratigraphy of the El Pui section. (a) Simplified chronostratigraphic column; (b) vertical variation in TOC; (c) vertical variation in TIC; (d) vertical variation in δ13Corg including the characteristic intra-segment C2 negative excursion denoted with a red arrow.

  • Figure 4

    Lithology and microfacies of selected samples prior to the lowest value of the intra-segment C2 negative excursion (blue), at the lowest value (red) and after (green). Refer to the legend for a detailed description of each symbol.

  • Figure 5

    (a) A-Trochospiral benthic foram (scale-100 μm), B-Planispiral evolute benthic foram infilled with framboidal pyrite (scale-100 μm), C-Roveacrinid fragments (scale-200 μm), D-Biserial benthic foram (scale-200 μm), E-Uniserial benthic foram (scale-100 μm), F-Holothurian ossicle (scale-100 μm); (b) K/L/M/N-Abundance of calcareous nannoplankton plates and fragments in smear-slide (scale-50 μm) and in SEM micrograph, A-Rare ammonite (cm scale), G-Echinoid spine (scale-100 μm), B-Rare gastropod (mm scale), C-Small sized planktonic foram [G.blowi] (scale-100 μm).

  • Figure 6

    Summary of organic geochemistry results and their respective stratigraphic locations along the δ13Corg curve. (a) Stratigraphic Height vs TAR; (b) n-alkane results for selected samples; (c) stratigraphic Height vs Pr/Ph. Colors (blue, red, green) refers to the duration before, during and after the lowest value reached within the intra-segment C2 negative excursion respectively.

  • Table 1   TIC, TOC, C, and TAR and Pr/Ph values in the El Pui section

    Sample ID

    Height (m)

    TIC

    TOC

    δ13Corg

    TAR

    Pr/Ph

    Sample ID

    Height (m)

    TIC

    TOC

    δ13Corg

    TAR

    Pr/Ph

    C-12-223*

    100.2

    50.3

    1.8

    −24.24

    C-11-161*

    57.9

    65.5

    0.8

    −24.15

    C-12-222*

    99.2

    50.8

    2.1

    −24.04

    C-11-160

    57.4

    61.2

    0.5

    −24.27

    C-12-221*

    97.4

    78.9

    1.7

    −24.7

    C-11-159*

    57

    57.9

    0.7

    −24.55

    C-12-220*

    96.1

    57.1

    2.4

    −24.03

    C-11-158

    56.7

    63.2

    0.4

    −25.25

    C-12-219*

    95.4

    47.8

    2.1

    −24.33

    C-11-157*

    56.3

    52.6

    0.7

    −24.27

    C-12-218*

    94.2

    46.2

    2.1

    −24.78

    C-11-156

    56.1

    66.2

    0.8

    −25.02

    C-12-217*

    93.6

    52.9

    1.4

    −24.18

    C-11-155*

    55.6

    66.4

    0.7

    −23.82

    C-12-216*

    92.5

    59.8

    1.4

    −24.13

    C-11-153*

    55.1

    63.5

    0.8

    −23.53

    C-12-215*

    90.9

    43.2

    1.7

    −24.44

    C-11-152

    54.9

    63.0

    0.6

    0.00

    1.26

    C-12-214*

    90.2

    42.8

    1.8

    −24.32

    C-11-151*

    54.3

    52.9

    0.8

    −23.98

    C-12-213*

    89.5

    44.5

    2.0

    −24.22

    C-11-150

    53

    63.8

    0.5

    C-12-212*

    88.9

    55.6

    0.4

    −23.95

    C-11-149*

    52.6

    65.0

    0.7

    −23.44

    C-12-211*

    88

    69.0

    0.8

    −24.48

    C-11-148

    52

    63.8

    0.5

    C-12-210

    87.3

    44.7

    1.7

    −24.08

    C-11-147*

    51.6

    77.7

    0.5

    −23.79

    C-12-209*

    86.6

    64.3

    2.0

    −24.73

    C-11-146

    51.5

    74.2

    0.5

    C-12-208

    86

    61.9

    1.5

    −24.84

    C-11-145*

    51.3

    67.9

    0.4

    −24.1

    C-11-207*

    84.5

    64.9

    0.6

    −25.33

    C-11-144

    51

    72.2

    0.6

    C-11-206

    83.1

    68.9

    0.6

    0.00

    1.22

    C-11-143*

    50.8

    68.5

    0.5

    −24.2

    C-11-205*

    81.1

    58.1

    0.7

    −25.36

    C-11-142

    50.6

    70.6

    0.6

    C-11-204

    79.6

    67.5

    0.3

    −25.74

    0.00

    0.71

    C-11-141*

    50.3

    71.0

    0.4

    −24.19

    C-11-203*

    78.3

    59.1

    0.7

    −25.89

    C-11-140

    49.9

    71.0

    0.6

    C-11-202

    77.2

    69.0

    0.5

    −26.26

    0.00

    1.02

    C-11-139*

    49.5

    67.6

    0.5

    −24.18

    C-11-201*

    75.7

    59.6

    0.7

    −25.95

    C-11-138

    48.9

    59.9

    0.9

    C-11-200

    74.1

    68.1

    0.4

    0.00

    1.40

    C-11-137*

    48.7

    61.5

    0.7

    −23.9

    C-11-199*

    73

    77.6

    0.6

    −25.93

    C-11-136

    48.5

    68.3

    0.7

    C-11-198

    71.5

    70.5

    0.4

    −25.7

    0.00

    0.84

    C-11-135*

    48

    75.0

    0.6

    −24.03

    C-11-197*

    70.7

    66.9

    0.8

    −24.45

    C-11-134

    47.8

    78.8

    0.4

    C-11-196

    70.6

    79.4

    0.8

    C-11-133*

    47.3

    73.7

    0.5

    −24.12

    C-11-195*

    70.2

    80.3

    0.4

    −25.52

    C-11-132

    47.1

    76.9

    0.6

    C-11-194

    70

    84.3

    0.9

    C-11-131*

    46.9

    75.3

    0.4

    −24.17

    C-11-193*

    69.7

    84.3

    0.3

    −24.9

    C-11-130

    46.7

    70.6

    0.6

    C-11-192

    69.5

    77.9

    0.7

    C-11-129*

    46.3

    70.0

    0.6

    −24.13

    C-11-191*

    69.3

    79.8

    0.4

    −25.42

    C-11-128

    46

    71.2

    0.6

    C-11-190

    69

    75.7

    0.7

    0.30

    1.15

    C-11-127*

    45.8

    72.1

    0.5

    −23.98

    C-11-189*

    68.8

    79.4

    0.4

    −25.47

    C-11-126

    45.6

    72.7

    0.6

    C-11-188

    68.5

    77.4

    0.7

    C-11-125*

    45.5

    74.0

    0.5

    −24.05

    C-11-187*

    68.3

    82.5

    0.4

    −24.81

    C-11-124

    45.2

    81.0

    0.5

    C-11-186

    68

    75.2

    0.6

    C-11-123*

    45

    75.9

    0.6

    −24.39

    C-11-185*

    67.6

    70.4

    0.6

    −24.6

    C-11-122

    44.9

    80.0

    0.6

    C-11-184

    67.3

    73.0

    0.5

    C-11-121*

    44.4

    75.7

    0.6

    −24.5

    C-11-183*

    67

    81.5

    0.6

    −24.55

    C-11-120

    44

    80.0

    0.6

    C-11-182

    66.5

    81.2

    0.6

    0.00

    1.11

    C-11-119*

    43.9

    77.3

    0.6

    −24.5

    C-11-181*

    66.3

    84.4

    0.4

    −25.25

    C-11-118

    43.7

    76.1

    0.7

    C-11-180

    65.8

    77.3

    0.6

    C-11-117*

    43.6

    80.7

    0.5

    −24.42

    C-11-179*

    65.4

    68.5

    0.6

    −24.32

    C-11-116

    43.5

    80.3

    0.6

    C-11-177*

    64.7

    69.6

    0.7

    −24.58

    C-11-115*

    43.1

    81.3

    0.5

    −24.32

    C-11-176

    64.4

    66.4

    1.2

    0.00

    1.32

    C-11-114

    42.9

    82.4

    0.6

    C-11-175*

    64

    69.2

    0.8

    −24.03

    C-11-113*

    42.7

    81.7

    0.4

    −24.33

    C-11-174

    63.9

    68.9

    0.6

    C-11-112

    42.5

    83.6

    0.6

    C-11-173*

    63.6

    72.5

    0.7

    −24.2

    C-11-111*

    42.3

    80.8

    0.5

    −24.27

    C-11-172

    63.3

    76.5

    0.5

    C-11-110

    42

    87.7

    0.5

    C-11-171*

    63.1

    79.4

    0.5

    −24.5

    C-11-109*

    41.8

    80.9

    1.0

    −24.25

    C-11-170

    62.5

    73.5

    0.9

    C-11-108

    41.5

    88.5

    0.5

    C-11-169*

    62

    59.6

    0.8

    −24.62

    C-11-107*

    41.3

    85.3

    0.4

    −24.08

    C-11-167*

    60.3

    76.5

    0.6

    −24.43

    C-11-106

    40.8

    79.4

    0.6

    0.34

    0.90

    C-11-166

    59.5

    66.6

    0.3

    −25.36

    0.00

    1.30

    C-11-105*

    40.5

    74.1

    0.7

    −24.2

    C-11-165*

    59.1

    71.6

    0.5

    −24.2

    C-11-104

    40.1

    79.3

    0.8

    0.38

    1.00

    C-11-164

    58.7

    60.7

    0.7

    −25.09

    C-11-103*

    39.4

    78.1

    0.5

    −24.27

    C-11-163*

    58.3

    68.4

    0.8

    −24.1

    C-11-102

    39

    75.6

    0.7

    C-11-162

    58.1

    69.6

    0.4

    −24.48

    The lowest value of the negative CIE occurs at a height of 77.2 m, corresponding to sample C-11-202. Samples with asterisks belong to values measured by Sanchez-Hernandez and Maurrasse (2014, 2016).

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