Tectonometamorphic evolution of the Western Rhodope complex - a record of multiple continent collision?

西罗多彼杂岩的构造变质演化——多个大陆碰撞的记录？

• 批准号: 19657490
• 负责人: Professor Dr. Nikolaus Froitzheim
• 金额: --
• 依托单位: Institut für Geologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2011-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/19657490?language=en
• 关键词: Tectonometamorphic; evolution; Western; Rhodope; complex

The Rhodope Complex in Bulgaria and Greece represents a stack of metamorphic thrust nappes recording a long history of Alpine orogenic deformation from Jurassic to present, including periods of thrusting and of extensional shearing and faulting. Previous work suggested that high- and ultrahigh-pressure metamorphism occurred at several times during the Alpine cycle (Jurassic, Cretaceous, and Tertiary). Our working hypothesis is that these metamorphic events resulted from multiple collisions of microcontinents, and that the exhumation of the high- and ultrahigh-pressure rocks resulted from processes inherent in multiple continent collision. We intend to study the kinematics, timing, and plate tectonic setting of these events by analysing the structural and metamorphic evolution of the western Rhodope complex (Rila, Pirin, West Rhodopes) in Bulgaria and Greece, using a combination of field mapping, kinematic analysis of shear zones (structures, microstructures and textures), metamorphic petrology (P-T-determi nation), and geochronology (U-Pb SHRIMP dating of zircon). The study area in the western part of the Rhodope complex is ideally suited for investigating the effects of multiple continent collision because of the presence of important shear zones, both compressional and extensional, of ophiolitic sutures, of pre-, syn- and posttectonic granitoid intrusions allowing to date the shear zones, and of Tertiary, detachment-related basins whose position and sediment fill record the late stages of extensional deformation and the unroofing of the metamorphic complexes.

保加利亚和希腊的罗多彼杂岩代表了一组变质逆冲推覆体，记录了从侏罗纪至今阿尔卑斯山造山变形的悠久历史，包括逆冲时期、伸展剪切和断层时期。先前的研究表明，高压和超高压变质作用在阿尔卑斯旋回（侏罗纪、白垩纪和第三纪）期间多次发生。我们的工作假设是，这些变质事件是由微大陆的多次碰撞造成的，而高压和超高压岩石的折返是由多个大陆碰撞所固有的过程造成的。我们打算通过结合野外测绘、运动学分析，分析保加利亚和希腊的西罗多彼杂岩（里拉、皮林、西罗多彼）的结构和变质演化，来研究这些事件的运动学、时间和板块构造背景。剪切带（结构、微观结构和纹理）、变质岩石学（P-T 测定）和地质年代学（锆石 U-Pb SHRIMP 测年）。罗多彼杂岩体西部的研究区域非常适合研究多大陆碰撞的影响，因为存在重要的压缩和拉伸剪切带、蛇绿缝合带、构造前、同构造和构造后花岗岩侵入体可以确定剪切带和第三纪、与滑脱相关的盆地的年代，这些盆地的位置和沉积物填充记录了伸展变形的晚期阶段和变质杂岩的脱顶。