Age, association and provenance of the “Neoproterozoic” fengshuigouhe group in the northwestern Lesser Xing’an Range, NE China: Constraints from zircon U-Pb geochronology

Abstract

The formation time of the Fengshuigouhe (风水沟河) Group in the northwestern Lesser Xing’an Range (小兴安岭), NE China, remains controversial owing to the lake of the precise dating data. This article reports zircon U-Pb ages for the leptynite and gneissic granitoids from the Fengshuigouhe Group in the northwestern Lesser Xing’an Range. The aim is to constrain the formation time and provenance of Fengshuigouhe Group. Field observation indicates that the Fengshuigouhe Group consists of a suit of metamorphic rocks (leptynite) and gneissic granitoids intruding the leptynite, and that both of them are cut by late granitic pegmatite. Zircons from two leptynites are euhedral-subhedral in shape and display oscillatory zoning in CL (cathodeluminescence) images. These detrital zircons give weighted mean ages of 255, 291, 321, 361, 469, and 520 Ma. The youngest age of them is interpreted to maximum depositional age of the protoliths of these leptynites. Zircons from gneissic granites are euhedral and subhedral in shape and exhibit typical oscillatory zoning in CL images. The dating results indicate that the gneissic granites were formed in the Early Jurassic (185±2 Ma). Zircons from the late granitic pegmatite are subhedral in shape and exhibit two types in CL images: structureless and oscillatory zoning. The former gives a weighted mean age of 143±1 Ma, considered to represent the timing of crystallization of the pegmatite, the latter yield several groups of ages: 178, 273, 319, 482, 611, and 788 Ma, representing the crystallization age of inherited or captured zircons entrained by the pegmatite. Taken together, we conclude that the Fengshuigouhe Group in the northwestern Lesser Xing’an Range formed between Late Paleozoic (255 Ma) to Early Mesozoic (185 Ma), rather than Neoproterozoic as previously believed, and that the sediments in the Fengshuigouhe Group were sourced directly from geological bodies in the study area and adjacent regions.

Keywords

the Lesser Xing’an Range / Fengshuigouhe Group / formation time / leptynite / zircon U-Pb geochronology

References

[1] Anderson T.. Correction of Common Lead in U-Pb Analyses that do not Report 204Pb. Chemical Geology, 2002, 192: 59-79.

[2] Chen B., Jahn B. M., Tian W.. Evolution of the Solonker Suture Zone: Constraints from Zircon U-Pb Ages, Hf Isotopic Ratios and Whole-Rock Nd-Sr Isotope Compositions of Subduction- and Collision-Related Magmas and Forearc Sediments. Journal of Asian Earth Sciences, 2009, 34(3): 245-257.

[3] Gao F. H., Xu W. L., Yang D. B., . LA-ICP-MS Zircon U-Pb Dating from Granitoids in Southern Basement of Songliao Basin: Constraints on Ages of the Basin Basement. Science in China (Series D), 2007, 50(7): 995-1004.

[4] Ge W. C., Sui Z. M., Wu F. Y., . Zircon U-Pb Ages, Hf Isotopic Characteristics and Their Implications of the Early Paleozoic Granites in the Northeastern Da Hinggan Mts., Northeastern China. Acta Petrologica Sinica, 2007, 23(2): 423-440.

[5] HBGMR (Heilongjiang Bureau of Geology and Mineral Resources), 1978. Report of 1: 200 000 Regional Geological Research (Longzhen Commune Sheets) (in Chinese)

[6] HBGMR Report of 1: 200 000 Regional Geological Research (Sunwu County Sheets), 1991, Beijing: Geological Publishing House

[7] HBGMR Regional Geology of Heilongjiang Province, 1993, Beijing: Geological Publishing House 1 734

[8] IMBGMR Regional Geology of Inner Mongolia, 1991, Beijing: Geological Publishing House 1 725

[9] Li J. Y., Niu B. G., Song B., . Crustal Formation and Evolution of Northern Changbai Mountains, Northeast China, 1999, Beijing: Geological Publishing House 1 136

[10] Li J. Y.. Permian Geodynamic Setting of Northeast China and Adjacent Regions: Closure of the Paleo-Asian Ocean and Subduction of the Paleo-Pacific Plate. Journal of Asian Earth Sciences, 2006, 26(3–4): 207-224.

[11] Liu Y. S., Hu Z. C., Gao S., . In Situ Analysis of Major and Trace Elements of Anhydrous Minerals by LA-ICP-MS without Applying an Internal Standard. Chemical Geology, 2008, 257(1–2): 34-43.

[12] Liu Y. S., Gao S., Hu Z. C., . Continental and Oceanic Crust Recycling-Induced Melt-Peridotite Interactions in the Trans-North China Orogen: U-Pb Dating, Hf Isotopes and Trace Elements in Zircons from Mantle Xenoliths. Journal of Petrology, 2010, 51(1–2): 537-571.

[13] Liu Y. S., Hu Z. C., Zong K. Q., . Reappraisement and Refinement of Zircon U-Pb Isotope and Trace Element Analyses by LA-ICP-MS. Chinese Science Bulle tin, 2010, 55(15): 1535-1546.

[14] Ludwig K. R.. ISOPLOT 3.00: A Geochronological Toolkit for Microsoft Excel. Berkeley Geochronology Center Special Publication, 2003, 4 74

[15] Miao L. C., Fan W. M., Zhang F. Q., . SHRIMP Zircon Geochronology and Its Implications on the Xinkailing-Keluo Complex, Northwestern of Lesser Xing’an Range. Chinese Science Bulletin, 2003, 48(22): 2315-2323.

[16] Miao L. C., Liu D. Y., Zhang F. Q., . Zircon SHRIMP U-Pb Ages of the “Xinghuadukou Group” in Hanjiayuanzi and Xinlin Areas and the “Zhalantun Group” in Inner Mongolia, Da Hinggan Mountains. Chinese Science Bulletin, 2007, 52(8): 1112-1124.

[17] Pei F. P., Xu W. L., Meng E., . The Beginning of the Paleo-Pacific Plate Subduction: Geochronological and Geochemical Evidence from the Early-Middle Jurassic Volcanic Rocks in the Eastern of Jilin and Heilongjiang Provinces. Bulletin of Mineralogy, Petrology and Geochemistry, 2008, 27 Suppl.l 268

[18] Shi G. H., Miao L. C., Zhang F. Q., . The Age and Its District Tectonic Implications on the Xilinhaote A-Type Granites, Inner Mongolia. Chinese Science Bulletin, 2004, 49(4): 384-389.

[19] Sui Z. M., Ge W. C., Wu F. Y., . U-Pb Chronology in Zircon from Harahaqi Granitic Pluton in Northeastern Daxing’anling Area and Its Origin. Global Geology, 2006, 25(3): 229-236.

[20] Sui Z. M., Ge W. C., Wu F. Y., . Zircon U-Pb Ages, Geochemistry and Its Petrogenesis of Jurassic Granites in Northeastern Part of the Da Hinggan Mts.. Acta Petrologica Sinica, 2007, 23(2): 461-480.

[21] Sun D. Y., Wu F. Y., Li H. M., . Emplacement Age of the Postorogenic A-Type Granites in Northwestern Lesser Xing’an Ranges, and Its Relationship to the Eastward Extension of Suolushan-Hegenshan-Zhalaite Collisional Suture Zone. Chinese Science Bulletin, 2000, 46(5): 427-432.

[22] Tang J., Xu W. L., Wang F., . Petrogenesis of Bimodal Volcanic Rocks from Maoershan Formation in Zhangguangcai Range: Evidence from Geochronology and Geochemistry. Global Geology, 2011, 30(4): 508-520.

[23] Wang F., Xu W. L., Meng E., . Early Paleozoic Amalgamation of the Songnen-Zhangguangcai Range and Jiamusi Massifs in the Eastern Segment of the Central Asian Orogenic Belt: Geochronological and Geochemical Evidence from Granitoids and Rhyolites. Journal of Asian Earth Science, 2011, 49: 234-248.

[24] Wang F., Xu W. L., Gao F. H., . Tectonic History of the Zhangguangcailing Group in Eastern Heilongjiang Province, NE China: Constraints from U-Pb Geochronology of Detrital and Magmatic Zircons. Tectonophysics, 2012, 566–567: 105-122.

[25] Wilde S. A., Zhang X. Z., Wu F. Y.. Extension of a Newly Identified 500 Ma Metamorphic Terrane in North East China: Further U-Pb SHRIMP Dating of the Mashan Complex, Heilongjiang Province, China. Tectonophysics, 2000, 328: 115-130.

[26] Wilde S. A., Wu F. Y., Zhang X. Z.. Late Pan-African Magmatism in Northeastern China: SHRIMP U-Pb Zircon Evidence from Granitoids in the Jiamusi Massif. Precambrian Research, 2003, 122: 311-327.

[27] Wu F. Y., Sun D. Y., Li H. M., . A-Type Granites in Northeastern China: Age and Geochemical Constraints on Their Petrogenesis. Chemical Geology, 2002, 187: 143-173.

[28] Wu F. Y., Yang J. H., Lo C. H., . The Heilongjiang Group: A Jurassic Accretionary Complex in the Jiamusi Massif at the Western Pacific Margin of Northeastern China. Island Arc, 2007, 16: 156-172.

[29] Wu F. Y., Zhao G. C., Sun D. Y., . The Hulan Group: Its Role in the Evolution of the Central Asian Orogenic Belt of NE China. Journal of Asian Earth Sciences, 2007, 30: 542-556.

[30] Wu F. Y., Sun D. Y., Ge W. C., . Geochronology of the Phanerozoic Granitoids in Northeastern China. Journal of Asian Earth Sciences, 2011, 41: 1-30.

[31] Wu G., Sun F. Y., Zhao C. S., . Discovery of the Early Paleozoic Post-Collisional Granites in Northern Margin of the Erguna Massif and Its Geological Significance. Chinese Science Bulletin, 2005, 50(23): 2733-2743.

[32] Wu Y. B., Zheng Y. F.. Genesis of Zircon and Its Constraints on Interpretation of U-Pb Age. Chinese Science Bulletin, 2004, 49(15): 1554-1569.

[33] Xu W. L., Ji W. Q., Pei F. P., . Triassic Volcanism in Eastern Heilongjiang and Jilin Provinces, NE China: Chronology, Geochemistry, and Tectonic Implications. Journal of Asian Earth Sciences, 2009, 34: 392-402.

[34] Zhang Y. L., Ge W. C., Gao Y., . Zircon U-Pb Ages and Hf Isotopes of Granites in Longzhen Area and Their Geological Implications. Acta Petrologica Sinica, 2010, 26(4): 1059-1073.

[35] Zhao Z., Chi X. G., Pan S. Y., . Zircon U-Pb LA-ICP-MS Dating of Carboniferous Volcanics and Its Geological Significance in the Northwestern Lesser Xing’an Range. Acta Petrologica Sinica, 2010, 26(8): 2452-2464.

[36] Zhou J. B., Wilde S. A., Zhang X. Z., . The Onset of Pacific Margin Accretion in NE China: Evidence from the Heilongjiang High-Pressure Metamorphic Belt. Tectonophysics, 2009, 478: 230-246.

[37] Zhou J. B., Wilde S. A., Zhao G. C., . Was the Easternmost Segment of the Central Asian Orogenic Belt Derived from Gondwana or Siberia: An Intriguing Dilemma?. Journal of Geodynamics, 2010, 50: 300-317.

[38] Zhou J. B., Wilde S. A., Zhang X. Z., . Detrital Zircons from Phanerozoic Rocks of the Songliao Block, NE China: Evidence and Tectonic Implications. Journal of Asian Earth Sciences, 2012, 47: 21-34.