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河北省怀来新元古代长龙山组主要为一套富含Chuaria等宏观藻类化石的碎屑岩沉积组合。对剖面的岩相分析及地球化学的研究，确定了潮坪、浅水陆棚及海滩等三种沉积相。由此提出了长龙山组的沉积相模式。长龙山组表现为三种沉积相的周期性叠里，组成了两个碎屑岩沉积序列。长龙山组的下部序列由湖坪相到浅水陆棚相再返回到海滩相；上部序列由浅水陆棚相及海滩相组成。Chuaria等宏观藻类化石主要发育在浅水陆棚相的滨外页岩亚相之中。综合分析表明，长龙山组是有河流参与的潮汐及波浪影响的滨浅海沉积环境。
The Neoproterozoic Changlongshan Formation in Huailai, Hebei Province is mainly a set of clastic sedimentary assemblages that are rich in macroscopic algal fossils such as Chuaria. By analyzing the lithofacies analysis and geochemistry of the profile, three sedimentary facies such as tidal flat, shallow water shelf and beach are identified. The sedimentary facies model of Changlongshan Formation is proposed. The Changlongshan Formation is characterized by periodic folding of three sedimentary facies, which consists of two sequences of clastic sediments. The lower sequence of the Changlongshan Formation returns from the lacustrine facies to the shallow shale facies to the beach facies. The upper sequence consists of a shallow shelf facies and a beach facies. Macroscopic macroalgal fossils such as Chuaria are mainly found in the submarine shale subfacies of shallow-water shelf facies. Comprehensive analysis shows that the Changlongshan Formation is a coastal shallow sea sedimentary environment that is affected by tides and waves with the participation of rivers.