Geochronology of subduction-related metamorphic rocks from the Central Indonesian Accretionary Collision Complex

印度尼西亚中部增生碰撞杂岩与俯冲相关的变质岩的年代学

基本信息

批准号：
313949328
负责人：
Professor Dr. Michael Bröcker
金额：
--
依托单位：
Institut für Mineralogie
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2016
资助国家：
德国
起止时间：
2015-12-31 至 2020-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/313949328?language=en
关键词：
Geochronology subduction related metamorphic rocks

项目摘要

This proposal seeks funding for field-based research activities that aim at establishing a solid geochronologic foundation for in-depth understanding of subduction- and collision-related metamorphic processes in the Central Indonesian Accretionary Collision Complex (CIACC). Previous studies have outlined the essential field, petrological and geochemical context of the metamorphic rocks from the CIACC. However, the knowledge about the timing and geodynamic significance of regional metamorphic processes is fragmentary and needs further attention. Relative to its geographic extent, the regional coverage with isotopic age data is insufficient under both quantitative and qualitative aspects for meaningful interpretation of the geologic history. Such data are crucial for a correct interpretation of the geologic histories and have the potential to significantly advance the understanding of the subduction–exhumation events recorded in the CIACC. New age data produced in a previous study focusing on metamorphic rocks from Bantimala (Sulawesi) and Luk Ulo (Java) revealed distinct age differences for the HP/LT stage that had previously not been recognized, due to the poor precision of an earlier K–Ar data set. The new geochronologic evidence has opened up new perspectives for an in-depth understanding of diverse metamorphic histories in different segments of the CIACC. More research is needed to fully understand the P–T–D–t evolution of the processes operating along the CIACC and to fully resolve the geotectonic context. A more comprehensive regional coverage is a prerequisite for an improved understanding of the geodynamic processes that have led to the formation of the pre-Tertiary accretionary complexes of the larger study area. For this purpose it will necessary to complement the existing data with age and P–T information for other occurrences, and to improve the knowledge of already studied locations by additional petrologic and age data. In order to establish a more comprehensive regional coverage with isotopic ages the logical next step is to focus on the metamorphic rocks from other parts of the CIACC. In this context the Meratus complex (south Kali-mantan) is of special importance for geodynamic considerations. New age data will help resolving spatial and temporal patterns in the geodynamic evolution on a broader regional scale, and will provide new insights into the development of the crustal architecture of Indonesia. The newly gained knowledge will provide a solid and robust foundation for refinement of palinspastic reconstructions, regional correlations and an improved interpretation of large-scale geodynamic processes in the central Indonesian region.

该提案为实地研究活动寻求资金，旨在为深入了解印度尼西亚中部增生碰撞杂岩（CIACC）中与俯冲和碰撞相关的变质过程奠定坚实的地质年代学基础，之前的研究已经概述了这一重要领域。然而，关于区域变质过程的时间和地球动力学意义的知识是零碎的，相对于其地理范围和区域覆盖范围，需要进一步关注。同位素年龄数据在定量和定性方面都不足以对地质历史进行有意义的解释，这些数据对于正确解释地质历史至关重要，并且有可能显着促进对记录在地俯冲-折返事件的理解。 CIACC 先前针对班提马拉（苏拉威西岛）和 Luk Ulo（爪哇）变质岩的研究产生的新年龄数据揭示了 HP/LT 阶段的明显年龄差异，而由于早期的精度较差，这一差异以前未被认识到。 K-Ar 数据集为深入了解 CIACC 不同部分的不同变质历史开辟了新的视角，以充分了解 P-T-D-t 演化。更全面的区域覆盖范围是更好地了解导致更大研究区域前第三纪增生杂岩形成的地球动力学过程的先决条件。为此，有必要用年龄和其他事件的 P-T 信息来补充现有数据，并通过额外的岩石学和年龄数据来提高对已研究地点的了解，以便建立更全面的同位素区域覆盖。合乎逻辑的下一步是关注 CIACC 其他部分的变质岩，在这种情况下，Meratus 复合体（南卡利曼丹）对于地球动力学考虑具有特别重要的意义，新时代数据将有助于解决该地区的空间和时间模式。这更广泛区域范围内的地球动力学演化，并将为印度尼西亚地壳结构的发展提供新的见解，新获得的知识将为细化回旋重建、区域相关性和改进大尺度解释提供坚实而有力的基础。印度尼西亚中部地区的地球动力学过程。