The definition and geological significance of tuffs about 1.85Ga in Yimen area, central Yunnan Province

LIU Junping; ZENG Wentao; XU Yunfei; SUN Baidong; HU Shaobin; LIU Guichun; SONG Donghu; LÜ Boye; WANG Xiaofeng

2018 Vol. 37, No. 11

Article Contents

Article navigation > Geological Bulletin of China > 2018 > 37(11): 2055-2062

Next Article Previous Article

LIU Junping, ZENG Wentao, XU Yunfei, SUN Baidong, HU Shaobin, LIU Guichun, SONG Donghu, LÜ Boye, WANG Xiaofeng. The definition and geological significance of tuffs about 1.85Ga in Yimen area, central Yunnan Province[J]. Geological Bulletin of China, 2018, 37(11): 2055-2062.

Citation:

LIU Junping, ZENG Wentao, XU Yunfei, SUN Baidong, HU Shaobin, LIU Guichun, SONG Donghu, LÜ Boye, WANG Xiaofeng. The definition and geological significance of tuffs about 1.85Ga in Yimen area, central Yunnan Province[J]. Geological Bulletin of China, 2018, 37(11): 2055-2062.

The definition and geological significance of tuffs about 1.85Ga in Yimen area, central Yunnan Province

1.
Yunnan Institute of Geological Survey, Kunming 650216, Yunnan, China
2.
Yunnan Provincial Institute of Environmental Monitoring, Kunming 650216, Yunnan, China
3.
Kunming University of Science and Technology, Kunming 650093, Yunnan, China

More Information

Corresponding author: ZENG Wentao, ynhjyzwt@163.com

Received Date: 20 March 2018

Revised Date: 25 June 2018

Publish Date: 15 November 2018

Abstract

Abstract

Medium-acid tuff was extensively found in Meidang Formation of Kunyang Group, which was determined by previous researchers in the west of Yimen-Luoci faults belt. Using the zircon laser denudation method (LA-ICP-MS), the authors obtained weighted average ages of 1842±26Ma (MSWD=7.6, n=29) and 1860±25Ma (MSWD=2.5, n=11) from dacitic tuff and quartz crystal tuff in Tongchang area, Yimen County, central Yunnan Province. Th/U ratios of zircon, which was of magmatic origin and with clear vibration band, were obtained from two samples (0.2~1.0). The tuff was found from a volcanic-microclastic rock assembly, which is over 1000m in thickness. There is a black slate-carbonate rock assembly, which is about 800m in thickness, under the volcanic-microclastic rock assembly. It is thus inferred that there is a large area of Paleoproterozoic strata, which are over 2000m in thickness in Yimen area of central Yunnan Province. The ages coincide with Columbia Supercontinent, and hence Yangtze block's location and significance ought to be taken into account in the reconstruction process of Columbia Supercontinent.
- Paleoproterozoic /
- zircon U-Pb age /
- Yimen area of central Yunnan Province /
- reconstruction process of Columbia Supercontinent

FullText(HTML)

References

[1]	吴懋德, 段锦荪, 宋学良, 等.云南昆阳群地质[M].昆明:云南科技出版社, 1990:1-265. Google Scholar
[2]	李希勣, 吴懋德, 段锦荪.昆阳群层序及顶底问题[J].地质论评, 1984, 30(5):399-408. doi: 10.3321/j.issn:0371-5736.1984.05.001 CrossRef Google Scholar
[3]	李复汉, 王福星, 申玉连, 等.康滇地区的前震旦系[M].重庆:重庆出版社, 1988:1-214. Google Scholar
[4]	戴恒贵.康滇地区昆阳群和会理群地层、构造及找矿靶区研究[J].云南地质, 1997, 16(1):1-39. Google Scholar
[5]	吕世琨, 戴恒贵.康滇地区建立昆阳群(会理群)层序的回顾和重要赋矿层位的发现[J].云南地质, 2001, 20(1):1-24. doi: 10.3969/j.issn.1004-1885.2001.01.001 CrossRef Google Scholar
[6]	杜远生, 张传恒, 韩欣, 等.滇中中元古代昆阳群的地震事件沉积及其地质意义[J].中国科学(D辑), 2001, 31(4):283-288. Google Scholar
[7]	张传恒, 高林志, 武振杰, 等.滇中昆阳群凝灰岩锆石SHRIMP U-Pb年龄华南格林威尔期造山的证据[J].科学通报, 2007, 52(7):818-824. doi: 10.3321/j.issn:0023-074X.2007.07.016 CrossRef Google Scholar
[8]	尹福光, 孙志明, 白建科.东川、滇中地区中元古代地层格架[J].地层学杂志, 2011, 35(1):49-54. Google Scholar
[9]	孙志明, 尹福光, 关俊雷, 等.云南东川地区昆阳群黑山组凝灰岩锆石SHRIMP U-Pb年龄及其地层学意义[J].地质通报, 2009, 28(7):898-900. Google Scholar
[10]	牟传龙, 林仕良, 余谦.四川会理-会东及邻区中元古界昆阳群沉积特征及演化[J].沉积与特提斯地质, 2000, 20(1):44-51. doi: 10.3969/j.issn.1009-3850.2000.01.003 CrossRef Google Scholar
[11]	周朝宪, 魏春生, 李朝阳.扬子地块西南缘下震旦系火成岩系研究[J].矿物学报, 1998, 18(4):405-41. Google Scholar
[12]	Kröner A, Jaeckel P, Williams I S. Pb-loss pattern in zircons from a high-grade metamorphic terrain as revealed by different dating methods:U-Pb and Pb-Pb ages for igneous and metamorphic zircons from nort-hern Sri Lanka[J]. Precambrian Research, 1994, 66:151-181. doi: 10.1016/0301-9268(94)90049-3 CrossRef Google Scholar
[13]	Hu Z C, Gao S, Liu Y S, et al. Signal enhance -ement in laser ablation ICP-MS by addition of nitrogen in the central channel gas[J]. Journal of Analytical Atomic Spectrometry, 2008, 23:1093-1101. doi: 10.1039/b804760j CrossRef Google Scholar
[14]	Hu Z C, Liu Y S, Gao S, et al. A "wire" signal smoothing device for laser ablation inductively coupled plasma mass spectrometry analysis[J]. Spectrochimica Acta Part B:Atomic Spectroscopy, 2012, 78:50-57. doi: 10.1016/j.sab.2012.09.007 CrossRef Google Scholar
[15]	Wiedenbeck M, Alle P, Corfu F, et al. Three natural zircon standards for U-Th-Pb, Lu-Hf, trace element and REE analyses[J]. Geostandards and Geoanalytical Research, 1995, 19(1):1-23. doi: 10.1111/ggr.1995.19.issue-1 CrossRef Google Scholar
[16]	Ludwing K R. Isoplot3.00: A Geochronologi -cal Toolkit for Microsoft Excel[M]. Berkelery: Berkeley Geochronology Center, 2003. Google Scholar
[17]	王海然, 赵红格, 乔建新, 等.锆石U-Pb同位素测年原理及应用[J].地质与资源, 2013, 22(3):229-242. doi: 10.3969/j.issn.1671-1947.2013.03.012 CrossRef Google Scholar
①	云南省地质调查院.云南1: 5万易门、二街等4幅区调项目. 2018. Google Scholar
②	云南省地质调查院《.云南省区域地质志》(第二版, 修测). 2018. Google Scholar