内蒙古二连盐池西岸上白垩统二连达巴苏组产出的恐龙化石一般呈脱离关节的堆积埋藏状态保存; 对于探讨和恢复该地区恐龙化石群落的组合面貌及其埋藏沉积过程具有重要意义。根据2014—2015年发现于二连盐池西部化石富集层的骨骼测量数据和埋藏状况判断: 超过50%的骨块化石归属于早期分支鸭嘴龙类姜氏巴克龙, 体现了其群居的生活习性; 恐龙群落在突发性集群死亡后经历了尸体腐烂、骨块机械性破损和物理风化的强烈影响以及多次洪水的搬运、堆积和埋藏过程, 最终形成了以巴克龙为单优势类群的脊椎动物尸积群; 古水流方向复杂多变, 反映了一种相对混乱的骨骼搬运环境; 水力分选在骨骼的搬运和埋藏过程中发挥了一定程度的作用; 巴克龙的种群年龄结构主要以未离巢和幼年阶段的个体为主, 强烈指示了损耗型死亡模式以及鸭嘴龙类幼年与成年种群分隔生活的特点。

Outcrops of the Upper Cretaceous Iren Dabasu Formation along the west bank of the Erlian Salt Lake have yielded abundant disarticulated dinosaur fossils that display taphonomic features characteristic of a hydraulically accumulated lag deposit. This discovery is significant for reconstructing the composition of the assemblage and the taphonomic and sedimentary history of the dinosaur community found in this area. Based on skeletal measurements and taphonomic data collected from the fossil-rich layer during fieldwork conducted in 2014 and 2015, more than 50% of the specimens from the bonebed are attributed to the early-branching hadrosauroid Bactrosaurus johnsoni, suggesting herding behavior of this species in life. Following catastrophic mass mortality events, the dinosaur community was strongly affected by the carcass decomposition, mechanical bone breakage, and physical weathering, ultimately resulting in a vertebrate bonebed mono-dominated by Bactrosaurus. Paleocurrent orientations are random and variable, reflecting a relatively chaotic process of hydraulic transportation of bones. Hydraulic sorting played only a minor role in bone transportation and burial. The age profile of the Bactrosaurus population is dominated by nestling and juvenile individuals, strongly indicating an attritional mortality pattern and suggesting population segregation between hadrosauroid juveniles and adults.

国家自然科学基金面上项目(42377447)和北科青年学者计划(24CE-YS-01)资助