δ 18 O apatite SST Zivi- le Urey 1 δ 18 O apatite δ 18 O SST ~ ~ δ 18 O SST 2 12 SST 13 biogenic calcite A

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1 GLOBAL GEOLOGY Vol. 32 No. 4 Dec : 利用生物成因磷灰石的氧同位素信息能够重建古海水温度, 尤其是牙形石, 结合其在生物地层学上的研究, 它的数据解释具有明确的古环境意义牙形石微小的个体一直是其精确地球化学分析的限制因素作为对牙形石微区原位氧同位素测试方法的探索研究, 本文利用 Cameca IMS 型二次离子质谱仪对牙形石进行了微区原位氧同位素组成测试, 通过分析得到可靠的古表层海水温度 ( SST) 记录, 表明从晚二叠世到早三叠世 SST 存在明显的上升过程相比常规 Ag 3 PO 4 实验方法, 牙形石微区原位氧同位素分析方法更加快速, 而且能够有效避免牙形石易受到污染的部位, 获得更为可靠的牙形石氧同位素组成的测定结果 : 牙形石 ; 氧同位素 ; 微区原位分析 ; 二次离子质谱 ; 古温度 : Q913. 2; P597. : A doi: /j. issn In situ oxygen isotope analysis of conodonts by SIMS and its implication for paleo-sea surface temperature WANG Run 1 CHEN Jian-bo 1 ZHAO Lai-shi 1 CHEN Yong-lin 1 TANG Guo-qiang 2 LI Xian-hua 2 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan China 2. State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Abstract Oxygen isotope composition of biogenic apatite especially of the conodonts is potentially useful in the reconstruction of contemporaneous surface seawater temperature SST. Combined with abundant researches on their biostratigraphy the geochemical analysis of conodonts is more significant for indicating paleoenvironmental changes. However the small size of conodont is always a factor limited for accurate analysis. In this work the authors test the in situ oxygen isotope of conodont using Cameca IMS-1280 secondary ion mass spectrometry SIMS for the first time and acquire reliable records on contemporaneous SST. The results show that SST raised rapidly from Late Permian to Early Triassic. Compared with the Ag 3 PO 4 method for popular use this analysis is faster in carrying out with high resolution and high spatial resolution and avoiding the contaminated position so as to acquire easily the reliable original oxygen isotopic compositions. Key words conodont oxygen isotope microanalysis in situ SIMS paleotemperature MSFGPMR lszhao@ cug. edu. cn

2 δ 18 O apatite SST Zivi- le Urey 1 δ 18 O apatite δ 18 O SST ~ ~ δ 18 O SST 2 12 SST 13 biogenic calcite Ag 3 PO 4 CO CO calcitic brachiopods belemnites foraminifera Trotter 22 SHRIMP 5 biogenic apatite or bio-apatite fish bones or fish teeth conodonts 70 phosphatic brachiopods 6-11 Cameca IMS -1280

3 O - O - 2 O + O + 2 Cs + 1 PBMF C N O S Cs Cameca IMS Table 1 Operating parameters for Cameca IMS-1280 testing oxygen isotope of conodont 133 Cs + 10kV D P /T ~ 2nA ~ 10μm - 10kV 30eV 2500 GSSP 23 P /T 24 ~ Cs μm a ~ 24e a ~ 27d 2 ~ 3 kg 16 O 18 O 2 cm 10% 20 1 ~ 2 d 4 s 2 min peak centering 5 min Li et Neogondolella Pa al CAI 2 2 Neogondolella Pa ppm ~ 1 inch cm 5 mm 1 ppb Durango apatite 22 NW - 18 O / 16 O VSMOW 18 O / 16 O = IMF δ 18 O 0. 01% ~ 10% δ 18 O M = 18 O / 16 O M IMF = δ 18 O M standard - δ 18 O VSMOW 2 δ 18 O sample = δ 18 O M - IMF 3 Cameca IMS -1280

4 655 1 Fig. 1 Sketch of measured conodont samples 3 Durango NW -1 Durango 9. 4 NW -1 69 Durango 0. 21 10-3 1SD 2 Durango NW - 1 5. 18 ± 0. 21 10-3 1SD 2 5. 2 ± 0. 3 10-3 9. 4 69 2 NW -1 0.

4 Fig. 1 Sketch of measured conodont samples 3 Durango NW -1 Durango 9. 4 NW Durango SD 2 Durango NW ± SD ± NW SD Table 2 Oxygen isotope results of internal laboratory 2 Durango standard apatite NW-1 Fig. 2 Measured international standard apatite Durango delta O 18 delta O 18 delta O 18 nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ nw -1@ Wheeley et al % < % 1 ~ % 2 ~ Wheeley

5 Ca 5 Na CO PO H 2 O F ~ PO 3-4 CO 2-3 H 2 O H 2 O CO 2-3 CO 2-3 H 2 O 6 CO ~ 40 CO 2-3 PO Table 3 3 D δ 18 O δ 18 O of conodont and calculated paleo - sea surface temperature from Meishan D Section IP na Intensity 16 O 16 O / 18 O Mean delta 18 O / 24a E E E E E E E E b E E E E E E E E b E E E E E E E E c E E E E E E c E E E E E E E E E E d E E E E E E E E e E E E E E E E E E E E E E E a E E b E E E E c E E d E E E E E E E E E E

6 4 657 δ 18 O water = pod shell calcite J. Palaeogeogr Palaeoclimatol Palae- oecol ~ Jaffrés J B D Shields G A Wallmann K. The oxygen i ~ sotope evolution of seawater a critical review of a longstanding controversy and an improved geological water cy Joachimski et al. 15 cle model for the past 3. 4 billion years J. Earth Sci Rev Wenzel B Lecuyer C Joachimski M M. Comparing oxygen isotope records of Silurian calcite and phosphate δ 18 O compositions of brachiopods and conodonts J. Geochim Cosmochim Acta Joachimski M M Buggisch W. Conodont apatite δ 18 O signatures indicate climatic cooling as a trigger of the Late Joachimski et al. 15 Devonian mass extinction J. Geology Joachimski M M van Geldern R Breisig S et al. Oxygen isotope evolution of biogenic calcite and apatite during the Middle and Late Devonian J. Int J Earth Sci Geol Rundsch Bassett D Macleod K G Miller J F et al. Oxygen isotopic composition of biogenic phosphate and the tempera- ture of early Ordovician seawater J. Palaios Buggisch W Joachimski M M Sevastopulo G et al. Mississippian δ 13 C carb and conodont apatite δ 18 O records-their relation to the Late Palaeozoic Glaciation J. Palaeogeogr Palaeoclimatol Palaeoecol igaite Joachimski M M Lehnert O et al. δ 18 O 3 composition of conodont apatite indicates climatic cooling during the Middle Pridoli J. Palaeogeogr Palaeoclimatol Palaeoecol Urey H C. The themodynamic properties of isotopic substances J. Journal of the Chemical Society YIN Guan NI Shi-jun. Isotope geochemistry M. Beijing Geological Publishing House Veizer J Ala D Azmy K et al. 87 Sr / 86 Sr δ 13 C and δ 18 O evolution of Phanerozoic seawater J. Chem Geol T = δ 18 O phosphate - δ 18 O seawater Geldern R V Joachimski M M Day J et al. Carbon oxygen and strontium isotope records of Devonian brachio- 12. M HAO Yi-chun MAO Shao-zhi. Micropaleontology M. Wuhan China University of Geosciences Press M. 13 Zhao L Chen Z Algeo T J et al. Rare-earth element patterns in conodont albid crowns evidence for massive

7 inputs of volcanic ash during the latest Permian biocrisis J. Glob Planet Change Joachimski M M Breisig S Buggisch W et al. Devonian climate and reef evolution insights from oxygen isotopes in apatite J. Earth Planet Sci Lett Joachimski M M Lai X Shen S et al. Climate warming in the latest Permian and the Permian-Triassic mass extinction J. Geology Elrick M Scott L A. Carbon and oxygen isotope evidence for high-frequency yr and my-scale glacio-eustasy in Middle Pennsylvanian cyclic carbonates Gray Mesa Formation Central New Mexico J. Palaeogeogr Palaeoclimatol Palaeoecol Kaiser S I Steuber T Becker R T. Environmental change during the Late Famennian and Early Tournaisian Late Devonian-Early Carboniferous implications from stable isotopes and conodont biofacies in southern Europe J. Geol J Trotter J A Eggins S M. Chemical systematics of conodont apatite determined by laser ablation ICPMS J. Chem Geol Trotter J A Fitzgerald J D Kokkonen H et al. New sights into the ultrastructure permeability and integrity of conodont apatite determined by transmission electron microscopy J. Lethaia Pietzner H Vahl J Werner H et al. Zur chemischen - zusammensetzung und mikromorphologie der conodonten J ZHAO Lai-shi WU Yuan-bao HU Zhao-chu et al. Trace element compositions in conodont phosphates responses to biotic extinction event a case study for main act of global boundary stratotype section and point of the Permian- Triassic J. Earth Science Joachimski M M Breisig S Buggisch W et al. Devonian climate and reef evolution insights from oxygen iso- 21. topes in apatite J. Earth Planet Sci Lett REE J CHEN Jian-bo ZHAO Lai-shi CHEN Zhong-qiang et al. Rare earth elements in situ in conodont from Meishan Section and implications for paleo-environmetal evolution J. Earth Science Trotter J A Williams I S Barnes C R et al. Did cooling oceans trigger Ordovician biodiversification evidence from conodont thermometry J. Science Yin H F Xie S C Luo G M et al. Two episodes of environmental change at the Permian-Triassic boundary of the GSSP section Meishan J. Earth-Science Reviews Li X H Li W X Wang X C et al. Role of mantle-derived magma in genesis of early Yanshanian granites in the Nanling range South China in situ zircon Hf-O isotopic constraints J. Science China Ser. D Li X H Long W G Li Q L et al. Penglai zircon megacrysts a potential new working reference material for microbeam determination of Hf-O isotopes and U-Pb age J. Geos Geoa Res Baertschi P. Absolute 18 O content of standard mean o- cean water J. Earth Planet Sci Lett Wheeley J R Smith M P Boomer I. Oxygen isotope variability in conodonts implications for reconstructing Palaeozoic palaeoclimates and palaeoceanography J. J Geol Soc J. Palaeontographica Abhandlungen Pucéat E Joachimski M M Bouilloux A et al. Revised phosphate-water fractionation equation reassessing paleotemperatures derived from biogenic apatite J. Earth Planet Sci Lett

km 5 km Pt 2 x 2 1 Au 65 ~ ~ km 5 km 10 km 2 Au Au

km 5 km Pt 2 x 2 1 Au 65 ~ ~ km 5 km 10 km 2 Au Au 38 1 2015 3 JOURNAL OF EAST CHINA INSTITUTE OF TECHNOLOGY Vol. 38 No. 1 Mar. 2015 doi 10. 3969 /j. issn. 1674-3504. 2015. 01. 002 1 2 1 2 3 1. 471000 2. 471000 3. 510640 9 P618. 51 A 1674-3504 2015 01-0012-11.