A new geological map of the Island of Syros (Aegean Sea, Greece): Implications for lithostratigraphy and structural history of the Cycladic Blueschist Unit
A new geological map of the Island of Syros (Aegean Sea, Greece): Implications for lithostratigraphy and structural history of the Cycladic Blueschist Unit
复制标题
锡罗斯岛（希腊爱琴海）的新地质图：对基克拉迪蓝片岩单元的岩石地层学和结构历史的影响
DOI：
10.1130/2011.2481
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
Tomaschek
中科院分区：
文献类型：
--
作者：
Keiter;Ballhaus;Tomaschek
锡罗斯岛（希腊基克拉泽斯）是研究造山带深层活动过程的主要地点，以其保存完好的蓝片岩-榴辉岩相岩性而闻名于世。锡罗斯岛完全以1：25，000的比例重新绘制。详细的岩石地层观察和区域范围内，紧密间隔的结构测量允许一个更详细的描述高度可变的岩性组合，以及复杂的结构演化。岩石地层学的迹象，如锰矿化的分布和连续重复的特征标记序列，表明整个岩石桩的基克拉迪蓝片岩单位锡罗斯，包括变质蛇绿岩和变质沉积物，保留了许多主要的沉积特征。岩浆活动在上白垩纪弧后环境可能是同期沉积的沉积原岩组成的主要岩性序列锡罗斯。锡罗斯基克拉迪蓝片岩单元的构造演化包括多期等斜叶内褶皱和韧性逆冲推覆，被认为基本上与埋藏有关，并在接近峰期变质条件时终止，要么是逆冲，要么是非常早的退变质路径。特别是在蓝片岩-榴辉岩相变质作用未受干扰的地区，高压组构保存完好。退变质演化伴随着不均匀分布的、弱发育的伸展构造和幕式收缩变形，随后伴随着强烈的脆性扭压和扭张构造，破坏了中新世至次近代以来的岩石序列。
The Island of Syros (Cyclades, Greece) is a prime locality for the study of processes active in deep levels of orogens and is world famous for its exceptionally well preserved blueschist-to eclogite-facies lithologies. Syros Island was completely remapped at a scale of 1: 25,000. Detailed lithostratigraphical observations and area-wide, closely spaced structural measurements allowed a much more detailed depiction of the highly variable lithological assemblage, as well as of the complex structural evolution. Lithostratigraphical indications, such as the distribution of Mn-mineralization and sequential repetition of characteristic marker successions, suggest that the whole-rock pile of the Cycladic Blueschist Unit on Syros, including meta-ophiolites and metasediments, retains numerous primary depositional features. Magmatic activity in an Upper Cretaceous backarc environment was likely to be contemporaneous with the deposition of the sedimentary protoliths comprising the main lithological succession on Syros. The structural evolution of the Cycladic Blueschist Unit on Syros comprises multiphase isoclinal intrafolial folding and ductile thrusting, regarded as essentially burial related and terminating close to peak metamorphic conditions, either prograde or very early on the retrograde path. Especially in areas where blueschist-to eclogite-facies metamorphism is undisturbed, high-pressure fabrics are well preserved. The retrograde evolution was accompanied by heterogeneously distributed, weakly developed extensional tectonics and episodical, contractional deformation, followed by intense brittle transpressional and transtensional tectonics, disrupting the rock sequence since Miocene to subrecent times.