|
|
THE LINJIA FORMATION IN BENXI, EAST LIAONING PROVINCE ASSIGNED TO MIDDLE TRIASSIC: Evidences from Zircon, Fossil and Stratigraphy |
ZHANG Yi1,2, ZHENG Shao-lin3, LI Zhi-tong3, CAO Cheng-run1,2, YANG Jia-lin3, ZHANG Guo-ren4, LI Xian-dong4, MENG Fan-wei5 |
1. College of Paleontology, Shenyang Normal University, Shenyang 110034, China; 2. Key Laboratory for Evolution of Past Life in Northeast Asia, Ministry of Natural Resources, Shenyang 110034, China; 3. Shenyang Center of Geological Survey, CGS, Shenyang 110034, China; 4. Liaoning Institute of Geological Exploration Co., Ltd., Dalian 116100, Liaoning Province, China; 5. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China |
|
|
Abstract The Linjia Formation is outcropped in Linjiawaizi area, Benxi, eastern Liaoning Province. Since recorded by Kobayashi in 1942, its age has long been a great controversy. In the early 1980s, Zhang et al. suggested that the Linjia Formation should be assigned to Middle Triassic on the basis of the plant fossils fish scales, insect wings, spores and pollens, as well as stratigraphic correlation. As the components of Linjia flora are very complicated with both Paleozoic and Mesozoic elements but without evidences of zircon ages, the age of Linjia Formation has not yet been determined. Recently, the metamorphic tuffaceous siltstones containing lots of zircons were found at the bottom of Linjia Formation. According to the dating results of 30 grains of zircon crystal, the average 206Pb/238U age of 4 newest zircons was 239.5±4.1 Ma. In addition, Pleuromeia shaolinii was lately discovered from Linjia Formation in Qiandianzi area. Although some significant fossil plants of Linjia flora are distributed striding cross Permian and Triassic, combined with the zircon dating, stratigraphic correlation, lithologic characteristics, parallel unconformity relation, typical Triassic fossil plants and the Middle Triassic-Early Cretaceous insect fossil Sogdoblatta, it is confirmed that the Linjia Formation belongs to Middle Triassic.
|
Received: 16 October 2019
|
|
|
|
|
[1] |
张武,郑少林,常绍泉. 辽宁本溪中三叠世林家植物群的研究[J]. 中国地质科学院沈阳地质矿产研究所所刊,1983,8:62-91.
|
[2] |
王钰,卢衍豪,杨敬之,等. 远东太子河流域地层(II)[J]. 地质学报, 1954,34(2):89-216.
|
[3] |
潘广,李振声,张恒谦,等. 太子河流域上古生界分层问题[J]. 地质论评,1959,19(6):277-279.
|
[4] |
李星学,周志炎,蔡重阳,等. 中国地质时代植物群[M]. 广州:广东科技出版社,1995:1-542.
|
[5] |
Zhang Y, Wang Y D, Zheng S L, et al. Pleuromeia from the Middle Triassic Linjia flora with typical Paleozoic elements recorded in Benxi, Northeast China[C]//Abstract book:the 5th International Palaeon-tological Congress, 2018:355.
|
[6] |
辽宁省地质矿产局. 辽宁省区域地质志[M]. 北京:地质出版社,1989.
|
[7] |
Compston W, Williams I S, Kirschvink J L, et al. Zircon U-Pb ages for the Early Cambrian time-scale[J]. J Geol Soc London, 1992,149:171-184.
|
[8] |
赖冬梅. 锆石U-Pb年龄不一致原因浅析[J]. 四川有色金属, 2004, 2:12-18.
|
[9] |
张海华,张健,黄欣. 突泉盆地突D2井林西组碎屑岩LA-ICP-MS锆石U-Pb年龄及地质意义[J]. 东北石油大学学报,2010,2:10-21.
|
[10] |
Taylor T N, Taylor E L, Krings M. Paleobotany-The biology and evolution of fossil plants[M]. Netherlands:Elsevier, 2009:1-1230.
|
[11] |
韩明慧,张宜,郑少林,等. 辽宁本溪中三叠世苏铁类密脉中国似查米亚[J]. 地质与资源,2018,27(1):22-32.
|
[12] |
Wachtler M. Swedenborgia nissleri, a characteristic conifer from the Middle Triassic German Hauptsandstein[C]//Wachtler M, ed. Fossil Triassic plants from Europe and their evolution. Volume 1:Conifers and Cycads. South Tyrol:Dolomythos Museum, 2016:114-121.
|
[13] |
Bugdaeva E. Podozamites and Swedenborgia from the Lower Cretaceous of Transbaikalia[J]. Paleontological Journal, 1995,29(2A):105-109.
|
[14] |
吴舜卿,周汉忠. 天山南部早三叠世植物化石初步研究[J]. 古生物学报,1990,29(4):447-459.
|
[15] |
Read C B, Mamay S H. Upper Paleozoic floral zones and floral province of the United States[J]. U. S. Geol Sur Prof Paper, 1964, 454(K):1-35.
|
[16] |
DUAN Shu-ying, CHEN Ye. On plant megafossils from the Late Triassic sediments of the eastern part of Sichuan Basin, China[J]. The Palaeobotanist, 1984,32(3):203-210.
|
[17] |
Kim J H, Kimura T. Lobatannularia nampoensis (Kawasaki) Kawasaki from the Upper Triassic Baegunsa Formation, Nampo Group, Korea[J]. Proc Jpn Acad Ser B Phys Biol Sci, 1988,64(8):221-224.
|
[18] |
中国科学院南京地质古生物研究所,中国科学院植物研究所. 中国植物化石(第一册)——中国古生代植物[M]. 北京:科学出版社, 1974:1-277.
|
[19] |
Dobruskina I A. Triassic floras of Eurasia[M]. New York:Springer-Verlag, 1994:1-422.
|
[20] |
洪友崇. 辽宁本溪林家组的蜚蠊化石(昆虫纲)及时代讨论[J]. 中国地质科学院沈阳地质矿产研究所所刊,1983,8:57-61.
|
[21] |
李星学. 华北月门沟群植物化石[J]. 中国古生物志,1963,新甲(6):1-185.
|
[22] |
黄枝高,周惠琴. 古植物[C]//中国地质科学院地质研究所, 编. 陕甘宁盆地中生代地层古生物(上册). 北京:地质出版社,1980:92-96.
|
[23] |
陕西省地质矿产局. 陕西省区域地质志[M]. 北京:地质出版社, 1989.
|
[24] |
山西省地质矿产局. 山西省区域地质志[M]. 北京:地质出版社, 1989.
|
[25] |
河南省地质矿产局. 河南省区域地质志[M]. 北京:地质出版社, 1989.
|
[26] |
河北省地质矿产局. 河北省区域地质志[M]. 北京:地质出版社, 1989.
|
[27] |
Kobayashi T. On the geology of the Penhsihu and Wafangtien areas in south Manchuria[J]. J Geol, 1942,54(643):349-363. (in Japanese)
|
|
|
|