The tectonomagmatic evolution of the Rhodope area, Bulgaria

保加利亚南部的罗多普地区构成了一个非常适合研究晚期到碰撞后构造体制中活跃过程的地形。作为涉及沉积学和构造研究的跨学科项目(Bündelantrag)的一部分，拟议项目的目的是研究(1)高压蛇绿岩和(2)碰撞后高钾火山岩。在该项目的头几个月，我们收集了一套广泛的样品，包括高压榴辉岩和镁铁质到长英质火山岩。取样的熔岩几乎涵盖了世界各地此类环境中发现的全部K元素富集区，包括钠长岩和苦铝石。在第一个模型中，这种成分扩散被解释为反映了俯冲过程中的可变来源富集度。高压榴辉岩的地温和Lu-Hf年代学初步结果表明，该榴辉岩经历了两个不同的峰期变质作用(白垩纪和第三纪)。在该项目的第二阶段，我们打算对火山岩进行更多的微量元素和同位素测量，并最终确定Lu-Hf和Sm-Nd年代学。这一结果将有助于全面认识高压地体的演化和高K岩浆作用的起源。

The Rhodope area in Southern Bulgaria constitutes a highly suited terrain to investigate processes active in a late- to post-collisional tectonic regime. As part of an interdisciplinary project (Bündelantrag) involving sedimentological and structural studies, the aim of the proposed project was to examine (1) HP ophiolites and (2) post-collisional high-K volcanic rocks. In the first months of the project we collected an extensive sample suite including HP eclogites and mafic to felsic volcanic rocks. The sampled lavas virtually cover the complete range of K enrichment found in such settings worldwide, including shoshonites and absarokites. In a first model, this compositional spread is interpreted to mirror variable source enrichment by subduction processes. Initial results on the geothermometry and Lu-Hf geochronology of the HP eclogites suggest two different periods of peak metamorphism (Cretaceous and Tertiary). In the second phase of the project, we intend to carry out additional trace element and isotope measurements on the volcanic rocks as well as to finalize Lu-Hf and Sm-Nd geochronology. The results will significantly contribute to the general understanding of the evolution of HP terrains and the origin of high-K magmatism.