We examined the lithostratigraphy and deformation structures of the accreted pelagic rocks in Lake Hamana area, Central Japan, based on a detailed field mapping and the radiolarian ages. The constructed lithostratigraphy is composed of Lopingian (Upper Permian) grey chert, black chert, black claystone with a high carbon content of 4.85–6.78 wt%, siliceous claystone, black chert, and Anisian (Middle Triassic) grey chert, in the ascending order. The symmetry in the lithostratigraphy and the change in the radiolarian ages with respect to black carbonaceous claystone are presumed to represent a deep‐sea anoxic event that occurred across the Permian–Triassic (P–Tr) boundary. The P–Tr boundary black carbonaceous claystone suffered from an intense shear, resulting in blocks of siliceous claystone in the scaly black claystone matrix. In places, the sheared terrigenous rocks composed of sandstone blocks in the mudstone matrix are intercalated into the pelagic rocks, possibly representing complex mélange forming processes during the development of the Jurassic accretionary complex.

中文翻译：

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日本中部滨名湖的侏罗纪增生复合体中的二叠纪-三叠纪边界段的保存

根据详细的田间制图和放射虫年龄，我们研究了日本中部滨名湖地区上层沉积的浮游岩石的岩石地层学和变形结构。人工岩石地层学由升平的罗平岩（上二叠纪）灰色石，黑色石，含碳量为4.85-6.78％（重量）的黑色黏土，硅质黏土，黑色cher石和Anisian（中三叠纪）灰色cher石组成。 。假定岩性地层学中的对称性以及相对于黑色碳质粘土岩的放射虫年龄的变化代表了跨二叠纪-三叠纪（P-Tr）边界发生的深海缺氧事件。P–Tr边界黑色碳质粘土经历了强烈的剪切作用，在鳞片状黑色粘土基质中形成了硅质粘土块。在地方