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This dissertation, "U-Pb Age and Hf Isotopic Study of Detrital Zircons From the Liaohe Group: Constraints on the Evolution of the Jiao-Liao-Ji Belt, North China Craton" by Yan, Luo,, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled U-Pb AGE AND Hf ISOTOPIC STUDY OF DETRITAL ZIRCONS FROM THE LIAOHE GROUP: CONSTRAINTS ON THE EVOLUTION OF THE JIAO-LIAO- JI BELT, NORTH CHINA CRATON Submitted by Luo Yan for the degree of Doctor of Philosophy at The University of Hong Kong in December 2005 The North China Craton (NCC) is the largest and oldest known continental block in China. The Jiao-Liao-Ji mobile belt along the eastern margin of the NCC is one of the rarely preserved Paleoproterozoic integrities in the world. As an important Paleoproterozoic sedimentary sequence of this belt, the Liaohe Group consists of an assemblage that includes a lower arkose- and volcanic-rich sequence (Langzishan, Li'eryu /Gaojiayu Formations), through a middle carbonate-rich sequence (Dashiqiao Formation) to an upper argillaceous sequence (Gaixian Formation). Traditionally, this group was subdivided into the North and South Liaohe Groups. Associated with the Liaohe Group are large volumes of granitoid rocks (Liaoji Granite), whose emplacement age has been dated at 2.1-2.2 Ga. Regionally, the Liaohe Group and the associated Liaoji Granite extend along a NEE-trending belt that is flanked by 2.45-2.55 Ga basement gneisses. Because of the lack of knowledge about the timing of deposition and metamorphism, nature of the sedimentary provenance and the basement, controversy exists on several issues including th