Hostname: page-component-76fb5796d-vvkck Total loading time: 0 Render date: 2024-04-29T13:13:00.864Z Has data issue: false hasContentIssue false

New age determination of the Cenozoic Lunpola basin, central Tibet

Published online by Cambridge University Press:  13 September 2011

HUAIYU HE*
Affiliation:
Key Laboratory of the Earth's Deep Interior, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
JIMIN SUN
Affiliation:
State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
QIULI LI
Affiliation:
State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
RIXIANG ZHU
Affiliation:
State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
*
Author for correspondence: huaiyuhe@mail.iggcas.ac.cn

Abstract

Knowing when the Tibetan Plateau reached its present elevation is important for understanding the uplift history of Tibet. Recently, Rowley & Currie (2006) suggested that central Tibet exceeded 4000 m from 35 Ma to the Pliocene using the oxygen-isotope composition of calcareous minerals in Lunpola basin sediments. However, they adopted a poor age assignment for the Dingqing Formation in the Lunpola basin based on previous microfossil studies. In this study, we present SIMS U–Pb zircon dates from a bentonite layer intercalated within the middle to lower Dingqing Formation. Twenty-six measurements yield a highly reliable U–Pb age of 23.5 ± 0.2 Ma (2σ, MSWD = 1.1), suggesting that the deposition age of the Dingqing Formation is late Oligocene to early Miocene, much older than the Miocene–Pliocene age used by Rowley & Currie (2006). This age robustly constrains the age of Cenozoic sedimentary strata in central Tibet, and hence provides an important basis for estimating the palaeoelevation in the high Tibet during the geological past.

Type
Rapid Communication
Copyright
Copyright © Cambridge University Press 2011

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

Aleinikoff, J., Wintsch, R., Fanning, M. & Dorais, M. 2002. U–Pb geochronology of zircon and polygenetic titanite from the Glastonbury Complex, Connecticut, USA: an integrated SEM, EMPA, TIMS, and SHRIMP study. Chemical Geology 188, 125–47.CrossRefGoogle Scholar
Black, L. P., Kamo, S. L., Allen, C. M., Davis, D. W., Aleinikoff, J. N., Valley, J. W., Mundil, R., Campbel, I. H., Korsch, R. J., Williams, I. S. & Foudoulis, C. 2004. Improved 206Pb/238U microprobe geochronology by the monitoring of a trace-element-related matrix effect; SHRIMP, ID-TIMS, ELA-ICP-MS and oxygen isotope documentation for a series of zircon standards. Chemical Geology 205, 115–40.CrossRefGoogle Scholar
Bureau Of Geology And Mineral Resources Xizang Autonomous Region. 1993. Regional Geology of Xizang (Tibet) Autonomous Region. Beijing: Geological Publishing House.Google Scholar
Coleman, M. & Hodges, K. 1995. Evidence for Tibetan plateau uplift before 14 Myr ago from a new minimum age for east-west extension. Nature 374, 4952.CrossRefGoogle Scholar
Fielding, E. J. 1996. Tibet uplift and erosion. Tectonophysics 260, 5584.CrossRefGoogle Scholar
Garzione, C. N., Dettman, D. L., Quade, J., Decelles, P. G. & Butler, R. F. 2000 a. High times on the Tibetan plateau: paleoelevation of the Thakkhola graben, Nepal. Geology 28, 339–42.2.0.CO;2>CrossRefGoogle Scholar
Garzione, C. N., Quade, J., Decelles, P. G.. & English, N. B. 2000 b. Predicting paleoelevation of Tibet and the Himalaya from δ18O vs. altitude gradients in meteoric water across the Nepal Himalaya. Earth and Planetary Science Letters 183, 215–29.CrossRefGoogle Scholar
Harrison, T. M., Copeland, P., Kidd, W. S. F. & Lovera, O. M. 1995. Activation of the Nyainqentanghla Shear Zone: implications for uplift of the southern Tibetan Plateau. Tectonics 14, 658–76.CrossRefGoogle Scholar
Ireland, T. & Williams, I. 2003. Considerations in zircon geochronology by SIMS. Reviews in Mineralogy and Geochemistry 53, 215–41.CrossRefGoogle Scholar
Kapp, P., Decelles, P. G., Gehrels, G. E., Heizler, M. & Ding, L. 2007. Geological records of the Lhasa–Qiangtang and Indo–Asian collisions in the Nima area of central Tibet. Geological Society of America Bulletin 119, 917–33.CrossRefGoogle Scholar
Li, Q. L., Li, X. H., Liu, Y. & Tang, G. Q. 2010. Precise U–Pb and Pb–Pb dating of Phanerozoic baddeleyite by SIMS with oxygen flooding technique. Journal of Analytical Atomic Spectrometry 25, 1107–13.CrossRefGoogle Scholar
Li, X. H., Liu, Y., Li, Q. L., Guo, C. H. & Chamberlain, K. R. 2009. Precise determination of Phanerozoic zircon Pb/Pb age by multicollector SIMS without external standardization. Geochemistry, Geophysics, Geosystems 10, Q04010, doi:10.1029/2009GC002400.Google Scholar
Ludwig, K. R. 2001. User's manual for Isoplot/Ex rev. 2.49. Berkeley Geochronological Center, Special Publication no. 1a.Google Scholar
Min, K., Mundil, R., Renne, P. R. & Ludwig, K. R. 2000. A test for systematic errors in 40Ar/39Ar geochronology through comparison with U/Pb analysis of a 1.1-Ga Rhyolite. Geochimica et Cosmochimica Acta 64, 7398.CrossRefGoogle Scholar
Rowley, D. B. & Currie, B. S. 2006. Palaeo-altimetry of the late Eocene to Miocene Lunpola basin, central Tibet. Nature 439, 677–81.CrossRefGoogle ScholarPubMed
Rowley, D. B., Pierrehumbert, R. T. & Currie, B. S. 2001. A new approach to stable isotope-based paleoaltimetry: implications for paleoaltimetry and paleohypsometry of the High Himalaya since the Late Miocene. Earth and Planetary Science Letters 188, 253–68.CrossRefGoogle Scholar
Spicer, R. A., Harris, N. B. W., Widdowson, M., Herman, A. B., Guo, S., Valdes, P. J., Wolfe, J. A. & Kelley, S. P. 2003. Constant elevation of Southern Tibet over the past 15 million years. Nature 412, 622–4.CrossRefGoogle Scholar
Stacey, J. S. & Kramers, J. D. 1975. Approximation of terrestrial lead isotope evolution by a two-stage model. Earth and Planetary Science Letters 26, 207–21.CrossRefGoogle Scholar
Steiger, R. H. & Jager, E. 1977. Subcommission on geochronology: convention on the use of decay constants in geo- and cosmochronology. Earth and Planetary Science Letters 36, 359–62.CrossRefGoogle Scholar
Turner, S., Arnaud, N., Liu, J., Rogers, N., Hawkesworth, C., Harris, N., Kelley, S., van Calsteren, P. & Deng, W. 1996. Post-collision, shoshonitic volcanism on the Tibetan Plateau: implications for convective thinning of the lithosphere and the source of ocean island basalts. Journal of Petrology 37, 4571.CrossRefGoogle Scholar
Wang, K. F., Yang, J. W., Li, Z. & Li, Z. R. 1975. On the Tertiary sporo-pollen assemblages from Lunpola Basin of Xizang, China and their palaeogeographic significance. Scientia Geologica Sinica 4, 366–74.Google Scholar
Wiedenbeck, M., Allé, P., Corfu, F., Griffin, W. L., Meier, M., Oberli, F., Von Quadt, A., Roddick, J. C. & Spiegel, W. 1995. Three natural zircon standards for U-Th-Pb, Lu-Hf, trace element and REE analyses. Geostandards Newsletter 19, 123.CrossRefGoogle Scholar
Williams, H. M., Turner, S., Kelley, S. & Harris, N. 2001. Age and composition of dikes in Southern Tibet: new constraints on the timing of east-west extension and its relationship to postcollisional volcanism. Geology 29, 339–42.2.0.CO;2>CrossRefGoogle Scholar
Xia, J. B. 1983. Cenozoic of Baingoin and its borders, Xizang (Tibet). In Contribution to the Geology of the Qinghai-Xizang (Tibet) Plateau (3) – Stratigraphy and Palaeontology (eds CGQXP Editorial Committee), pp. 243–54. Beijing: Geological Publishing House.Google Scholar
Xia, W. G. 1982. Age and ostracode fossils of the Lunpola Group in the Lunpola Basin, Baingoin County, Tibet. In Proceedings of Tibetan Geology (10) (eds The 4th Geological Survey Brigade, Geological Bureau of Xizang), pp. 149–59. Beijing: Geological Publishing House.Google Scholar
Xu, Z. Y. 1980. The Tertiary and its petroleum potential in the Lunpola Basin, Tibet. Oil and Gas Geology 1, 153–8.Google Scholar
Yuan, C. P. & Xu, S. H. 2000. Characteristics of geotemperature field and maturity history of source rocks in Lunpola basin, Xizang (Tibet). Experimental Petroleum Geology 22, 157–8.Google Scholar