克拉通岩石圈三维物质架构示踪方法

doi:10.13745/j.esf.sf.2023.5.81

地学前缘 ›› 2023, Vol. 30 ›› Issue (6): 391-405.DOI: 10.13745/j.esf.sf.2023.5.81

克拉通岩石圈三维物质架构示踪方法

杨立强¹^,²(), 和文言¹, 高雪¹, 王偲瑞¹, 李楠¹, 邱昆峰¹, 张良¹, 马强³, 苏玉平³, 李大鹏², 张智宇⁴, 于红¹

1.中国地质大学(北京) 地质过程与矿产资源国家重点实验室, 北京 100083
2.自然资源部金矿成矿过程与资源利用重点实验室/山东省金属矿产成矿地质过程与资源利用重点实验室/山东省地质科学研究院, 山东济南 250013
3.中国地质大学(武汉) 地质过程与矿产资源国家重点实验室, 湖北武汉 430074
4.中国地质科学院地质研究所, 北京 100037

收稿日期:2022-04-30 修回日期:2023-05-07 出版日期:2023-11-25 发布日期:2023-11-25
作者简介:杨立强(1971—),男,教授,博士生导师,主要从事矿床学及矿产普查与勘探的教学和科研工作。E-mail: lqyang@cugb.edu.cn
基金资助:
国家重点研发计划项目(2019YFA0708603);国家自然科学基金项目(42130801);国家自然科学基金项目(41572069);高等学校学科创新引智计划项目(BP0719021);中国地质大学地质过程与矿产资源国家重点实验室专项基金项目(MSFGPMR201804)

New method to trace the three-dimensional compositional structure of cratonic lithosphere

YANG Liqiang¹^,²(), HE Wenyan¹, GAO Xue¹, WANG Sirui¹, LI Nan¹, QIU Kunfeng¹, ZHANG Liang¹, MA Qiang³, SU Yuping³, LI Dapeng², ZHANG Zhiyu⁴, YU Hong¹

1. State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences (Beijing), Beijing 100083, China
2. Ministry of Natural Resources Key Laboratory of Gold Mineralization Processes and Resources Utilization/Key Laboratory of Metallogenic-Geologic Processes and Comprehensive Utilization of Minerals Resources in Shandong Province/Shandong Institute of Geological Sciences, Jinan 250013, China
3. State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences (Wuhan), Wuhan 430074, China
4.Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China

Received:2022-04-30 Revised:2023-05-07 Online:2023-11-25 Published:2023-11-25

摘要/Abstract

摘要：

克拉通岩石圈三维物质组成架构示踪是当今地球科学研究前沿,面临系列挑战。在对已有相关成果系统梳理的基础上,分别阐述了实现由点到面、由局部到全时空、由单一方法到多学科综合约束3个战略思路转变的基本要点;并以华北克拉通为例,提出了亟待深化的研究领域和未来方向。多种地球物理方法联立约束和综合解释,不仅开拓了岩石圈物质组成研究的新思路,而且有利于获得更可信的结果。逼近实际的岩石圈物质组成架构必须符合岩石探针、岩石圈物性结构、岩石物理性质与矿物及化学组成的测试分析/模拟计算结果等观测事实,并遵循地球化学热力学-地球动力学理论框架;这就需克服单一资料和方法各自的局限性,由单一手段向多方法综合约束转变,实现多学科融合来开展岩石圈物质组成的研究。据此提出“循序渐进、逐步深化”和“反馈修正、不断逼近”的岩石圈物质组成架构的多学科综合示踪研究流程。华北克拉通岩石圈三维物质架构研究的重点在于通过多学科的深度融合,恢复不同时期的构造格架和对应的物质组成,示踪其岩石圈物质架构的演变过程。

关键词: 岩石圈物质组成架构, 岩石探针, 同位素填图, 地球物理反演, 多学科融合, 华北克拉通

Abstract:

Tracing the three-dimensional compositional structure of cratonic lithosphere is a frontier research topic in earth sciences, and it faces a series of challenges. This paper systematically examines previous results and proposes a new way of tracer study, i.e., changing from point to surface tracing, from local to whole-area tracing, and from single- to multi-method tracing. Taking the North China Craton as an example, urgent research areas and future directions are also proposed. The use of a single constrain and a comprehensive structural interpretation, obtained by multidisciplinary synthesis using various geophysical methods, not only opens up a new way of studying the three-dimensional compositional structure of the lithosphere, but also is conducive to obtaining more reliable results. A more realistic compositional structural model must agree with observations, including rock probe, lithospheric architecture, petrophysical property and mineral composition data, and be consistent with the theoretical geochemical thermodynamic and geodynamic frameworks. To overcome single data/method limitations and to obtain a joint constrain, a multidisciplinary tracer study process adhering to “systematic, gradual progress” and “feedback correction and continuous approximation” is proposed, which aims to recover the compositional structures of cratonic lithosphere in different evolutionary stages and trace its evolutionary process.

Key words: compositional structure of the lithosphere, petrological probe, isotopic mapping, geophysical inversion, multidisciplinary integration, North China Craton

中图分类号:

杨立强, 和文言, 高雪, 王偲瑞, 李楠, 邱昆峰, 张良, 马强, 苏玉平, 李大鹏, 张智宇, 于红. 克拉通岩石圈三维物质架构示踪方法[J]. 地学前缘, 2023, 30(6): 391-405.

YANG Liqiang, HE Wenyan, GAO Xue, WANG Sirui, LI Nan, QIU Kunfeng, ZHANG Liang, MA Qiang, SU Yuping, LI Dapeng, ZHANG Zhiyu, YU Hong. New method to trace the three-dimensional compositional structure of cratonic lithosphere[J]. Earth Science Frontiers, 2023, 30(6): 391-405.

图/表 2

图1 克拉通岩石圈物质组成架构的多学科综合示踪研究流程

Fig.1 Flowchart of comprehensive, multidisciplinary tracer study of the compositional structure of cratonic lithosphere

图2 胶东半岛岩石圈三维物质架构模型 Hf-Nd同位素等值线图均在Surfer软件中根据岩浆岩的经纬度坐标和相应的εHf(t)和εNd(t)中位值,使用距离幂函数反比加权法完成。其中Hf同位素等值线图的数据源为胶东地区中生代花岗岩中U-Pb同位素年龄在160~95 Ma区间范围内的944个锆石数据点[129⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓-140];Nd同位素等值线图的数据源为胶东地区130~95 Ma的基性岩全岩Nd同位素数据129件[141⇓⇓⇓⇓⇓⇓⇓⇓-150]。

Fig.2 3D compositional structural model for the Jiaodong Peninsula (isotope data from [129⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓-150])

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克拉通岩石圈三维物质架构示踪方法

New method to trace the three-dimensional compositional structure of cratonic lithosphere

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