Hostname: page-component-7bb8b95d7b-w7rtg Total loading time: 0 Render date: 2024-09-15T15:20:38.124Z Has data issue: false hasContentIssue false
  • English
  • Français

Microdiamonds, their classification and tectonic implications for the host eclogites from the Dabie and Su-Lu regions in central eastern China

Published online by Cambridge University Press:  05 July 2018

Shutong Xu ,
Yican Liu ,
Guanbao Chen ,
Shouyuan Ji ,
Pei Ni  and
Wanshen Xiao
Shutong Xu*
Affiliation:
Anhui Institute of Geology, 19 Ningguo Road, Hefei, 230001, China Laboratory of Continental Dynamics of Ministry of Land and Resources of China, Beijing, 100037, China
Yican Liu
Affiliation:
Anhui Institute of Geology, 19 Ningguo Road, Hefei, 230001, China China University of Sciences and Technology, Hefei, 230026, China
Guanbao Chen
Affiliation:
Anhui Institute of Geology, 19 Ningguo Road, Hefei, 230001, China
Shouyuan Ji
Affiliation:
Department of Earth Sciences, Nanjing University, Hankou Road, Nanjing, 210008, China
Pei Ni
Affiliation:
Department of Earth Sciences, Nanjing University, Hankou Road, Nanjing, 210008, China
Wanshen Xiao
Affiliation:
Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
*
*E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

We have found >10 in situ microdiamonds in thin sections of eclogites from the Dabie and Su-Lu regions of central eastern China since the first occurrence of microdiamond in eclogites from the Dabie Mountains (DMT) reported in 1992. The microdiamonds are found not only in the central part but also in the northern part of the DMT. Several free crystals have been recovered from the crushed eclogites from the central DMT. Most in situ microdiamonds are inclusions in garnets but a few larger ones are intergranular. Most of the diamondiferous eclogites in the central part of the DMT are associated with coesite. Most importantly, the observation of microdiamonds in northern Dabie lead us to question the supposition that this is a low-P metamorphic terrane. All the diamondiferous eclogites from both the north and central DMT are of continental affinity as demonstrated by their negative εNd values. Therefore, both the north and central eclogite belts in the DMT are considered to be from the deep subducted terrane. Five in situ microdiamonds and two free crystals are first reported in this paper. The dimensions of the in situ microdiamonds are 30–180 µm and the free crystals are up to 400–700 mm across. All the microdiamonds are confirmed as such by Raman spectroscopy. The results of an infrared spectroscopic investigation on two larger free crystals and two in situ microdiamonds show that all the microdiamonds from both the Dabie and Su-Lu regions are mixed types IaA and IaB diamonds and there is no indication of any synthetic microdiamonds in our samples because such synthetic microdiamonds are always rich in type Ib.

Keywords

microdiamondRamaninfrared spectroscopyDabie MountainsSu-Lu regionChina
Type
Research Article
Information
Mineralogical Magazine , Volume 69 , Issue 4 , August 2005 , pp. 509 - 520
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2005

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bucher, K. and Frey, M. (1994) Petrogenesis of Metamorphic Rocks. Springer-Verlag, Berlin, 318 pp.CrossRefGoogle Scholar
Carmichael, I.S.E., Turner, F.J. and Verhoogen, J. (1960) Igneous Petrology. McGraw-Hill Book Company, 739 pp.Google Scholar
Condie, K.C. (1989) Plate Tectonics and Crustal Evolution, 3rd edition. Pergamon Press, Oxford, UK, pp. 165–207.CrossRefGoogle Scholar
Cong, B., Zhai, M., Carswell, D.A., Wilson, R.H., Wang, Q., Zhao, Z. and Windley, B.F. (1995) Petrogenesis of ultrahigh-pressure rocks and their country rocks in Shuanghe of Dabieshan, central China. European Journal of Mineralogy, 7, 119—138.Google Scholar
Cong, B., Zhang, R., Liou, J.G., Ye, K. and Wang, Q. (1996) Metamorphic evolution of UHPMR. Pp. 128—160 in: Ultrahigh-pressure Metamorphic Rocks in Dabie-Sulu Region of China (Cong, B., editor). Science Press, Bejing, Kluwer Acdemic Publishers, Dordrecht, The Netherlands.Google Scholar
Chrenko, R.M., Tuft, R.E. and Strong, H.M. (1977) Transformation of the state of nitrogen in diamond. Nature, 4, 141–144.CrossRefGoogle Scholar
De Corte, K., Cartigny, P., Shatsky, V.S., Sobolev, N.V. and Javoy, M. (1998) Evidence of fluid inclusions in metamorphic microdiamonds from the Kokchetav massif, northern Kazakhstan. Geochimica et Cosmochimica Acta, 62, 3765–3773.CrossRefGoogle Scholar
Dobrzhinetskaya, L.F., Eide, E.A., Larsen, R.B., Start, B.A., Tronnes, R.G., Smith, D.C., Taylor, W.R. and Posukhova, T.V. (1995) Microdiamond in high-grade metamorphic rocks of the Western Gneiss region, Norway. Geology, 23, 597—600.2.3.CO;2>CrossRefGoogle Scholar
Eide, E. (1995) A model for the tectonic history of the HP and UHPM region in east central China. Pp. 391—426 in: Ultrahigh-Pressure Metamorphism (Coleman, R.G. and Wang, X., editors). Cambridge, University Press, UK.CrossRefGoogle Scholar
Haggerty, S.E. and Sautter, V. (1990) Ultradeep (greater than 300 kilometers) ultramafic upper mantle xenoliths. Science, 248, 993–996.CrossRefGoogle ScholarPubMed
Li, S., Jagoutz, E.,Xiao, , Ge, N. and Chen, Y. (1996) Chronology of ultrahigh-pressure metamorphism in the Dabie Mountains and Sulu terrane: (i) Sm-Nd isotope system. Science in Chian (Series D), 39, 597–609.Google Scholar
Liu, Y., Xu, S., Li, S., Jiang, L., Wu, W., Chen, G. and Su, W. (2000) Eclogites from the Northern Dabie Mountains, eastern China: Geochemical characteristics, Sr and Nd isotopic compositions and tectonic implications. Science in China (Series D), 43 (supplement), 178–188.CrossRefGoogle Scholar
Maruyama, S., Liou, J.G. and Zhang, R.Y., (1994) Tectonic evolution of the ultra-high pressure and high-pressure metamorphic belts from central China. The Island Arc, 3, 112–121.CrossRefGoogle Scholar
Massonne, H.J. (1999) A new occurrence of micro-diamonds in quartzo-feldspathic rocks of the Saxonian Erzgebirge, Germany, and their meta-morphic evolution. Proceedings of the 7th International Kimberlite Conference, Cape Town, pp. 533–539.Google Scholar
Okay, A.I., Xu, S. and Sengor, A.M.C. (1989) Coesite from the Dabie Shan eclogite, central China. European Journal of Mineralogy, 1, 595—598.CrossRefGoogle Scholar
Orlov, L. (1973) MИHPAΓИ ЯπMA3A [Mineralogy of Diamonds] (Translated to Chinese, 1977), Published in Beijing, 175 pp.Google Scholar
Sobolev, N.V. and Shatsky, V.S. (1990) Diamond inclusions in garnets from metamorphic rocks: a new environment for diamond formation. Nature, 343, 742–745.CrossRefGoogle Scholar
Su, W., Xu, S., Jiang, L. and Liu, Y. (1996) Coesites from quartz jadeitite in Dabie Mountains, eastern China. Mineralogical Magazine, 60, 639–662.CrossRefGoogle Scholar
van Roermund, H.L.M., Carswell, D.A., Drury, M.R. and Heijboer, T. C. (2002) Microdiamonds in a megacrystic garnet websterite pod from Badane on the island of Fjørtoft, western Norway: Evidence for diamond formation in mantle rocks during deep continental subduction. Geology, 39, 959–962.2.0.CO;2>CrossRefGoogle Scholar
Wang, Q., Cong, B., Zhai, M. and Sparks, J.W. (1994) A possible Paleozoic island arc: petrologic evidences from North Dabie gneiss. Pp. 37–47 in: Annual Report of the Laboratory of Lithosphere Tectonic Evolution (1993-1994) Institute of Geology, Academia Sinica, (editor). Seismological Press, Beijing.Google Scholar
Wang, Q. and Cong, B. (1996) Tectonic implication of UHP rocks from the Dabie Mountains. Science in China (Series D), 39, 311–318.Google Scholar
Wang, X. and Liou, J.G. (1991) Regional ultrahigh-pressure coesite-bearing eclogite terrane in central China: evidence from country rocks, gneiss, marble, and metapelite. Geology, 19, 933–936.2.3.CO;2>CrossRefGoogle Scholar
Wang, X., Liou, J.G. and Mao, H.G. (1989) Coesite-bearing eclogites from the Dabie Mountains in central China. Geology, 17, 1085–1088.2.3.CO;2>CrossRefGoogle Scholar
Wang, X., Cui, W., Liu, S., Zhang, L. and Wei, C. (1993) Discovery of coesite-bearing eclogite in south Henan. Acta Petrologica Sinica (in Chinese with English abstract), 9, 181.Google Scholar
Xie, X., Guo, J. and Chen, F. (1999) Physics of the Gem Mineralogy of China (in Chinese). Science Press of Guangdong Province, Guangzhou, China, 272 pp.Google Scholar
Xu, Z. (1987) Etude tectonique et microtectonique de la Chaine Paleozoique et Triassique des Qinglings (Chine). These de doctorat, Univ. Sci. Tech. Languedoc, Montpelier, France, pp. 95—97.Google Scholar
Xu, S., Okay, A.I., Ji, S., Sengör, A.M.C., Su, W., Liu, Y. and Jiang, L. (1992) Diamond from the Dabie Shan metamorphic rocks and its implication for tectonic setting. Science, 256, 80–82.Google Scholar
Xu, S., Liu, Y., Jiang, L., Su, W. and Ji, S. (1994) Tectonic regime and evolution of Dabie Mountains (in Chinese with English abstract). Science Press, Beijing, 175 pp.Google Scholar
Xu, S., Liu, Y., Su, W., Jiang, L., Wu, W. and Wang, R. (2000) Discovery of the eclogite and its petrography in the Northern Dabie Mountain. Chinese Science Bulletin, 45, 273–278.CrossRefGoogle Scholar
Xu, S., Liu, Y. and Wu, W. (2001) A paradox: the ultramafic rock belt (UMRB) as a metamorphosed tectonic mélange in Northern Dabie Mountains, Eastern central China. Pp. 323—342 in: Paradoxes in Geology (Briegel, U. and Xiao, W., editors). Elsevier, Amsterdam.Google Scholar
Xu, S., Liu, Y., Wu, W., Chen, G., Jiang, L., Compagnoni, R. and Rolfo, F. (2002a) Eclogite in the northern Dabie Mountains: petrography and tectonic implications. Pp. 92–104 in: Academic Papers for 80th Anniversary of the Geological Society of China (Chen, Y., editor). Geological publishing House, Beijing (in Chinese with English abstract).Google Scholar
Xu, S., Liu, Y., Jiang, L., Wu, W. and Chen, G. (2002b) Architecture and Kinematics of the Dabie Mountains Orogen: Hefei. University of Science and Technology of China Press, 133 pp.Google Scholar
Xu, S., Liu, Y., Chen, G., Compagnoni, R., Rolfo, F., He, M. and Liu, H. (2003) New finding of microdiamonds in eclogites from Dabie-Sulu region in central eastern China. Chinese Science Bulletin, 48, 988–994.CrossRefGoogle Scholar
Xu, S., Liu, Y., Chen, G. and Wu, W. (2005) Architecture and kinematics of the Dabie orogen, central eastern China. Acta Geologica Sinica, 3, 356–371.Google Scholar
Yang, J., Xu, Z. and Bai, W. (1999) The discovery of diamond in the eclogite from the Sulu region. Earth Science Front, 6, 69 (in Chinese).Google Scholar
Yang, J., Xu, Z., Pei, X., Shi, R. and Wu, C. (2002) Discovery of diamond in North Qinling: evidence for a giant UHPM belt across central China and recognition of Paleozoic and Mesozoic dual deep subduction between North China and Yangtze plates. Acta Geologica Sinica, 76, 484–495.(in Chinese with English abstract).Google Scholar
Ye, K., Cong, B. and Ye, D. (2000) The possible subduction of continental material to depths greater than 200 km. Nature, 407, 734–736.CrossRefGoogle ScholarPubMed
Zhai, M., Cong, B., Zhao, Z., Wang, Q., Wang, G. and Jiang, L. (1995) Petrologic-tectonic units in the coesite-bearing metamorphic terrain of the Dabie Mountains, central China and their geotectonic implications. Journal of southeast Geoscience, 11, 1–13.Google Scholar
Zhang, R., Liou, J.G., Wang, X., Wang, Q. and Liu, X. (1993) Discovery of coesite from eclogite in Henan, central China and its geological significance. Acta Petrologica Sinica (in Chinese with English abstract), 9(2), 186.Google Scholar
Zhang, R.Y., Liou, J.G. and Tsai, C.H. (1996) Petrogenesis of a high-temperature metamorphic terrain: a new tectonic interpretation for the north Dabie Shan, central China. Journal of Metamorphic Geology, 14, 319–333.CrossRefGoogle Scholar