The Fort Munro Formation is 200-m-thick mixed carbonate–siliciclastic succession of Late Cretaceous (Campanian) age exposed at the Rakhi Nala Section, Sulaiman Range, Lower Indus Basin, Pakistan. The Fort Munro Formation is representing thin- to thick-bedded limestone with interbedded marls, shale and sandstone. Detailed microfacies analysis revealed the recognition of 15 microfacies types (11 carbonate and 4 sandstone). These facies were deposited on both inner and middle ramp platform. The inner ramp sediments are more widespread than the corresponding middle ramp including open-marine, skeletal shoals, semi-restricted, carbonate sand shoals and banks and lagoon depositional environments. The uppermost part of the Fort Munro Formation has received sufficient amount of siliciclasts, thereby producing a sandstone texture. These siliciclasts indicate the tectonic uplift, which thereby increases the source area rejuvenation. Therefore, a mixed carbonate–siliciclastic, moderately storm-dominated homoclinal ramp depositional environment is suggested for the Fort Munro Formation.

中文翻译：

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巴基斯坦苏莱曼山脉Rakhi Nala剖面上白垩统Fort Munro组微相分析及沉积环境

Fort Munro 组是在巴基斯坦下印度河流域苏莱曼山脉 Rakhi Nala 剖面出露的晚白垩世 (Campanian) 时代的 200 米厚的碳酸盐-硅质碎屑混合层序。Fort Munro Formation 代表薄层至厚层石灰岩与夹层泥灰岩、页岩和砂岩。详细的微相分析显示识别出 15 种微相类型（11 种碳酸盐岩和 4 种砂岩）。这些相沉积于内斜坡台地和中间斜坡台地。内斜坡沉积物比相应的中斜坡沉积物更广泛，包括开放海洋、骨骼浅滩、半限制性碳酸盐沙浅滩以及河岸和泻湖沉积环境。Fort Munro 组的最上部已接收到足够数量的硅质碎屑，从而产生砂岩质地。这些硅质碎屑表明构造隆升，从而增加了源区的复兴。因此，建议 Fort Munro 组为碳酸盐-硅质碎屑混合、中等风暴主导的同斜斜坡沉积环境。