Dating of low-grade high-pressure Metamorphism in the Afyon Zone; W-Anatolia

在第一次实地考察期间（2007-2008年），研究人员确定了土耳其西南部以及整个Afyon地区和安纳托利亚东部Bitlis地块的低等级高压岩石的范围和分布。这一发现证明了一个主要的蓝片岩带的持续存在，该蓝片岩带位于kir<s:1> ehir地块以南，形成了安纳托利亚中部高原。这些发现，它们的范围以及与北部的塔夫桑里带和南部的陶尔人的关系，清楚地证明了基尔塞希尔块体以南的新特提斯的一个分支，这一事实受到许多土耳其同事的强烈质疑。在土耳其西部从北到南不断发现较年轻的HP变质作用的背景下，我们建议确定变质作用的年龄，以约束Afyon HP带的发掘历史。这包括利西亚推覆体和门德雷斯地块的部分覆盖层。阿菲永HP带以含镁铁碳酸岩、蓝片岩相变质岩为特征。在变质的河流三角洲层序中发现了镁铁碳绿岩作为造岩矿物。铁镁碳榴石只存在于无钠长石中，多数与辉云岩伴生。因此，钠肯定已经被完全浸出，而钾则留在这些岩石中。因此，我们开始进行岩相和地球化学研究，以了解变质前的风化/蚀变和沉积条件，这些条件导致岩石成分容易形成mg - fe - carphoolite。这些调查将在赠款期间继续进行。

During the first field based period of this grant (2007-2008) extent and distribution of low-grade high-pressure rocks in SW Turkey and along the entire Afyon Zone and the Bitlis Massif in Eastern Anatolia was confirmed. The findings demonstrate the continuous existence of a major blueschist belt running south of the Kirşehir block, that forms the Central Anatolian plateau. These findings, their extent and the relation towards the Tavsanli zone in the north as well as the Taurids in the South clearly plead for a branch of the Neotethys south of the Kirsehir block, a fact that is highly contested by many Turkish colleagues. In the context of successively younger ages found in HP metamorphism of Western Turkey form North to South, we propose to determine the age of metamorphism for constraining the exhumation history of the Afyon HP belt. This includes the Lycian nappes and parts of the cover sequence of the Menderes Massif. The Afyon HP belt is characterized by Mg-Fe-carpholite bearing, blueschist facies metapelites. We found Mg-Fe-carpholite as rock forming mineral in a metamorphosed fluvio-deltaic sequence. Fe-Mg-carpholite occurs exclusively in albite free rocks, mostly associated with phengite. Thus, Na must have been leached completely, while K remained in these rocks. We therefore started performing lithofacies and geochemical investigations for understanding the pre-metamorphic weathering/alteration and sedimentation conditions which led to rock compositions prone to form Mg-Fe-carpholite. These investigations will continue during this grant period.