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Detrital Zircon U-Pb Geochronology and Its Provenance Implications on Silurian Tarim Basin

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Detrital Zircon U-Pb Geochronology and Its Provenance Implications on Silurian Tarim Basin Journal of Earth Science, Vol. 23, No. 4, p. 455–475, August 2012 ISSN 1674-487X Printed in China DOI: 10.1007/s12583-012-0268-z Detrital Zircon U-Pb Geochronology and Its Provenance Implications on Silurian Tarim Basin Jingyan Liu* (刘景彦) School of Energy Resources, China University of Geosciences, Beijing 100083, China Changsong Lin (林畅松) School of Ocean Sciences, China University of Geosciences, Beijing 100083, China Sitian Li (李思田) Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education, China University of Geosciences, Wuhan 430074, China; School of Energy Resources, China University of Geosciences, Beijing 100083, China Zhenzhong Cai (蔡振忠) Institute of Petroleum Exploration and Exploitation, Tarim Oil Field Company, PetroChina, Korla 841000, China Shiqiang Xia (夏世强), Chao Fu (付超), Yongquan Liu (刘永权) School of Ocean Sciences, China University of Geosciences, Beijing 100083, China ABSTRACT: As one of the major exploration objects of marine deposit in Tarim basin, Silurian has been paid more attention from oil/gas exploration and geologists. However, due to the widely deposit and later erosion, it is difficult to restore the original basin. The surrounding tectonic activity and provenance systems of Silurian Tarim basin have a lot of controversy. Aid of detrital zircons U-Pb dat- ing data obtained from well drilling of Tabei (塔北) and Tazhong (塔中) areas and Sishichang (四十场) and Xiangyangcun (向阳村) outcrop profiles, integrated with other geological and geophysical data, the tectothermal evolution and provenance nature of Silurian deposit have been revealed. Zircons U-Pb dating shows Tarim basin has experienced 5–6 significant tectothermal events: 3 500–3 000 Ma Paleo–Mesoarchean, around 2 500 and 1 800 Ma Paleoproterozoic, around 1 000 and 800 Ma Neopro- terozoic, and 500–400 Ma Eopaleozoic tectothermal events. These tectothermal events reflected the evolution of Tarim microplates and Tarim basin, respectively, corresponded to the forming and spilit- ting process of Ur supercontinent, Kenorland, Columbia and Rodinia supercontinent. Difference between the samples of Tazhong and Tabei areas This study was supported by the Fundamental Research Funds indicated that North and South Tarim mi- for the Central Universities of China (No. 2010ZD07), the Key croplates were different in Paleo–Mesoarchean, National Natural Science Foundation of China (No. 41130422), and later evolutions were more synchronous the National Natural Science Foundation of China (No. after Paleoproterozoic. Integrated with seismic 40372056) and the State Key Development Program for Basic data and outcrop interpretation, the U-Pb dating Research of China (Nos. 2011CB201103, 2006CB202302). results also revealed that the surrounding tec- *Corresponding author: [email protected] tonic activities were still very active during Silu- © China University of Geosciences and Springer-Verlag Berlin rian, and indicated different regions had differ- Heidelberg 2012 ent source systems. At Tadong (塔东) and Manjiaer (满加尔) depressions, major source Manuscript received January 15, 2012. systems came from Ordovician Altyn orogenic belts. Manuscript accepted April 8, 2012. At Tabei area and northwest of Tarim basin, major 456 Jingyan Liu, Changsong Lin, Sitian Li, Zhenzhong Cai, Shiqiang Xia, Chao Fu and Yongquan Liu source systems came from recycling orogenic zone (the activity of South Tianshan (天山) Mountain) and Precambrian stable basement (local paleo-uplifts at north of Tabei). The Ordovician uplift and orogenic zone at the south of Tarim basin and Precambrian granite basement provided lots of source systems to Tazhong area. KEY WORDS: provenance analysis, zircon U-Pb geochronology, tectonic setting, Silurian, Tarim basin. INTRODUCTION provenance, depositional systems and favorable Tarim basin, the largest basin in west of China, reservoir distribution are all hot topics worth of developed on pre-Sinian basement and suffered deep discussion. However, due to the widely deposit multi-stages tectonic evolution, is a bearing energy and later erosion, it is difficult to restore the origi- resources and superimposed basin (Jia, 1997). From nal basin. Archaeozoic to Mesozoic and Cenozoic, the basin had In recent years, with the development of ad- experienced long term tectonic reformation and many vanced dating technology, such as zircon LA-ICP-MS, original basins superimposition (Lin et al., 2009; He et SHRIMP U-Pb dating and apatite fission track meth- al., 2005). The long history and complex basin struc- ods, it is possible to provide accurate chronological ture and surrounding tectonic setting made it old basin evidence for basin evolution and provenance systems, with abundant geological significances (Chen et al., and further discuss the surrounding tectonic back- 1996), and attractive to more and more attention of ground. Restoration orogenic events and the research geologists. Meanwhile, Tarim basin is rich in coal, oil on coupling of basin and mountain always are the hot and gas resources (Kang, 2007; Zhou et al., 2007), and theme of the international geological field, and has now it has already become one of the most important made lots of progress (Glorie et al., 2010; Long et al., resource bases of China’s Western Development 2010; Qiu et al., 2010; Li Z et al., 2009; Narelle et al., Strategy. For a long time, the unique geological back- 2009; Li Y P et al., 2007; Cawood and Nemchin, 2000; ground, basin structure and depositional filling, tec- Wysoczanski et al., 1997; Dickinson et al., 1983). In tonic evolution and oil/gas bearing condition of Tarim this article, 4 samples have been carried out for detri- basin have attracted wide interests of geologists and tal zircon U-Pb dating with LA-ICP-MS method. exploration industry (Ren et al., 2011; Cai, 2005; Among them, 3 samples were taken from Silurian Zhang et al., 2002; Kang and Kang, 1996; Li et al., sandstone and 1 sample came from Devonian sand- 1996). Its comparison with other basins of the world stone (sample code: Jm-1). Two samples came from or the relationship with global significant events also well drilling (Jm-1 and Tc-1, taken from Tabei and are research topics with high scientific significances Tazhong, respectively) and 2 were taken from out- (Xu et al., 2011; Jia et al., 2007; Jin and Wang, 2004). crops (SSC-28 and XYC-1, taken from the Sishichang The surrounding tectonic activity and provenance outcrop profile at the northwest of Tarim basin and systems of Silurian Tarim basin have a lot of contro- Xiangyangcun outcrop profile at Kuruktag uplift of versy. Due to the thick deposit (over 10 km in the ba- the east of Tarim basin, respectively). In addition, sin) and deep subsidence during the long geological there is another Devonian sandstone sample taken history, it is more difficult to reveal the old basement from Well Hd14 at Tabei area, which has been fin- and quantify the key tectonic evolution events, which ished debris zircon U-Pb dating (Liu et al., 2012). has made very important influence on the tectonic and Therefore, there are 5 samples, respectively repre- sedimentary evolution in basin, and are worth to deep senting the 5 major parts of Tarim basin, showed the discuss in further research. Silurian, as one of the ma- whole tectothermal events history before Neoprotero- jor exploration objects of marine deposit in Tarim ba- zoic of Tarim basin, and also revealed the difference sin, has been paid more attention from oil/gas explo- of different places. The zircons ages determination in ration and geologists (Kang, 2007; Liu et al., 2004; the Tarim basin provides isotope chronological evi- Song and Wu, 2004; Song et al., 2003). Silurian sur- dence for further exploration the relationship between rounding tectonic background and its basin nature, Tarim microplate and the surrounding supercontinent. Detrital Zircon U-Pb Geochronology and Its Provenance Implications on Silurian Tarim Basin 457 Based on the tectonic-stratigraphic framework in the original basin with different characteristics at different basin, quantitative research and comprehensive analy- locations resulted in the unique sequence structure of sis of multiple data provides strong evidences and superimposed basin and hydrocarbon accumulation constraint for determining the regional tectonic setting, process in western China. The tectonization and evo- basin evolution and significant tectonic events, un- lution around the basin have deep influences on tran- conformities, and sedimentary filling characteristics sition of palaeotectonics and paleogeography in the responsed to tectothermal events. Silurian detrital zir- basin and generation and accumulation of hydrocar- cons U-Pb dating results also indicate that different bon resources (Liu J Y et al., 2011, 2010; Lin et al., regions have different source systems, which will be 2009; Liu L F et al., 2001). very helpful to analyse the sedimentary development and distribution, and further give a guidance to predict Basin Filling and Tectonic Evolution Sequence favorite reservoir sedimentary systems. In terms of tectonic setting and sedimentary fill- ing evolution of the basin, the Tarim basin has ex- REGIONAL GEOLOGICAL BACKGROUND perienced several important tectonic evolutions and Tectonic Location of the Basin formed multiple unconformities, including (from old 0 Tarim basin is located in the west of China, be- to new) the base of Sinian (T10 ), the base of Siluria 0 0 tween the gigantic Tianshan Mountain and Kunlun (T7 ), the base of Upper Devonian (T6 ), the base
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