The Bayankhoshuu Ruins section in southern Mongolia is characterized by strongly thrusted and folded sequences. Overall, three sections ranging from Ordovician to Carboniferous rocks were studied. Facies analysis combined with stratigraphic data provide improved lithostratigraphic descriptions of Palaeozoic successions in the Mushgai region. The overall marine sedimentary sequence is punctuated by volcanic rocks–basaltic lava of Silurian and Middle Devonian age and volcaniclastic bentonite and tuff in the Middle to Late Devonian and Mississippian suggesting an island arc setting. The Minjin Member of the Botuulkhudag Formation (Middle Devonian to Late Devonian) is primarily composed of thick basaltic and subaerial volcanic rocks with minor silicified siltstone and chert inclusions. Thicker successions of limestone occur in the Ordovician/Silurian, Early Devonian, and the Mississippian. The macrofauna is scarce, except distinct limestone horizons where different fossil groups were recognized. Microfossils, such as radiolarians and conodonts, are scarce and generally poorly preserved. However, based on the re-study of collections from earlier publications and new conodont data, a more detailed biostratigraphic record of the Khoyormod, Botuulkhudag, and Arynshand formations of the Bayankhoshuu Ruins section can be developed. For instance, the Arynshand Formation likely ranges from the late Bispathodus ultimus conodont biozone to the Scaliognathus anchoralis–Doliognathus latus conodont biozone. A tectonic breccia occurs in the early Mississippian and is overlain by a red shale of remarkable thickness at the top of this formation which points to subaerial exposure in the early Mississippian (near the Tournaisian/Visean transition). Due to strong tectonic overprint and/or facies, some unconformities/hiatuses occur. Most strata are intensively folded and faulted, ranging from centimeter to meter scale. Overall, deposition likely occurred on either the Mandalovoo or Gurvansayhan Terrane.

蒙古南部的Bayankhoshuu遗址部分具有强烈的冲断和折叠序列。总的来说，研究了从奥陶纪到石炭纪的三个剖面。相分析与地层数据相结合，提供了改进的穆什盖地区古生代演替的岩相地层学描述。整个海洋的沉积序列被火山岩点刺–志留纪和中泥盆世时代的玄武质熔岩以及中晚泥盆世和密西西比州的火山碎屑膨润土和凝灰岩表明岛为弧形。Botuulkhudag组（中泥盆世至晚泥盆世）的Minjin成员主要由厚的玄武岩和陆上火山岩组成，并具有少量硅化粉砂岩和石包裹体。在奥陶纪/西律纪，早泥盆纪和密西西比纪都出现了较厚的石灰岩层序。大型动物区系稀少，除了可识别不同化石群的独特石灰岩层位。诸如放射虫和牙形石的微化石是稀缺的，而且通常保存不善。但是，根据对早期出版物和新牙形石数据的重新研究，可以更详细地记录科伊莫特（Khoyormod），Botuulkhudag，Bayankhoshuu遗址部分的Arynshand地层可以开发。例如，Arynshand组可能从晚期比目鱼双歧牙形生物带到Scaliognathus anchoralis – Doliognathus latus牙形生物带。构造角砾岩发生在密西西比早期，在该构造的顶部被厚厚的红色页岩覆盖，这表明密西西比早期（突尼斯/维森过渡附近）暴露于地下。由于强烈的构造叠印和/或相，会出现一些不整合面/断层。大多数地层都被强烈折叠和断裂，范围从厘米到米。总体而言，沉积可能发生在Mandalovoo或Gurvansayhan Terrane上。