The Upper Cretaceous Nilkanth Formation awaits a process-based depositional model despite being a topic of discussion between stratigraphers, palaeobiologists and structural geologists over the last few decades. Sedimentary facies analysis of a ~50 m thick section along a ~2.8 km long section along Rishikesh–Tal Bidhashini in Pauri Garhwal district of Uttarakhand allowed documentation of mixed carbonate–silicicalstic facies types, dominantly consisting of sand- and pebble-sized carbonate debris mixed with siliciclastics in a proximal to distal facies tract. Ten different facies types that include matrix-rich and matrix-poor shelly conglomerate, mixed clastic-carbonate wackestone, packstone, impure calcirudite and calcarenite, biomicrite and ferruginous sandstone are documented. Delineation of facies association and documentation of facies stacking pattern provide a post-Santonian mixed carbonate–siliciclastic sedimentation history of the Nilkanth Formation, deposited in the form of mass flows of varied rheology on a barred low- to moderate-gradient carbonate ramp, formed at the leading edge of the India plate before its collision with the Kohistan–Ladakh arc. Carbonate clasts comprising bivalves, crinoids, algae, bryozoan, etc., were produced in a narrow high-energy transgressive coastline and supplied across shelf along with reworked siliciclastics from clastic shoreface bar. It is argued that the reworked fossils, including the bryozoa Ceriocava Nilkanthi, present within massflows may not justify fixing of an absolute age for the formation but may definitely help in providing an age range.

尽管在过去的几十年中，地层学家，古生物学家和结构地质学家一直在讨论上白垩统Nilkanth地层，但仍在等待基于过程的沉积模型。在北阿坎德邦Pauri Garhwal地区的Rishikesh–Tal Bidhashini沿约2.8 km长的一段约50 m厚的剖面上进行了沉积相分析，从而形成了混合的碳酸盐－硅质相类型的文档，主要由砂砾和卵石大小的碳酸盐碎片组成在近端至远端相中含有硅质碎屑。记录了十种不同的相类型，包括富基质和贫基质的贝壳状砾岩，混合碎屑碳酸盐瓦克石、,石，不纯的钙硅钙石和钙钙石，生物云母和铁质砂岩。相界的描述和相堆积模式的记录提供了Nilkanth组的后桑顿期碳酸盐-硅质碎屑混合沉积历史，以各种流变学的质量流形式沉积在禁止的中低梯度碳酸盐岩斜坡上。在印度板块与Kohistan–Ladakh弧线碰撞之前的前沿。碳酸盐岩碎屑包括双壳类，海藻，藻类，苔藓虫等，在狭窄的高能海侵海岸线上生产，并与碎屑岸面棒中经过重制的硅质碎屑一起提供给整个货架。据认为，返工的化石，包括苔藓动物 在印度板块的前缘与科伊斯坦–拉达克弧线碰撞之前形成的低至中度梯度的碳酸盐梯度斜面上以各种流变形式的质量流形式沉积。碳酸盐岩碎屑包括双壳类，海藻，藻类，苔藓虫等，在狭窄的高能海侵海岸线上生产，并与碎屑岸面棒中经过重制的硅质碎屑一起提供给整个货架。据认为，返工的化石，包括苔藓动物 在印度板块的前缘与科伊斯坦–拉达克弧线碰撞之前形成的，由低至中梯度的碳酸盐禁止的斜面上以变化的流变质量流形式沉积。碳酸盐岩碎屑包括双壳类，海藻，藻类，苔藓虫等，在狭窄的高能海侵海岸线上生产，并与碎屑岸面棒中经过重制的硅质碎屑一起提供给整个货架。据认为，返工的化石，包括苔藓动物存在于质量流中的Ceriocava Nilkanthi可能不能证明确定岩层的绝对年龄是合理的，但可以肯定地有助于确定年龄范围。