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山东东部诸城晚白垩世王氏群大面积、高密度集群埋藏的恐龙化石是近年研究的热点,但其沉积物源与精确沉积时限目前尚不明确。本文通过对山东诸城王氏群恐龙化石层中6个砂岩样品的碎屑锆石U-Pb定年表明,样品090414-24-D中最年轻的单颗粒锆石年龄(YSG)为77.3 Ma,应代表王氏群恐龙化石层的最大沉积时限(下限),结合前人对王氏群红土崖组的年代学研究表明,其沉积时限应老于73.5 Ma(上限),也说明赋存恐龙化石层的王氏群上部红土崖组为Campanian期沉积;碎屑锆石定年揭示物源的锆石年龄组成分布在100～130 Ma之间,6个样品的年龄主峰值多在110 Ma或120 Ma左右,与下伏的早白垩世青山群火山岩年龄主峰较为吻合。王氏群恐龙化石层砾岩的砾石成分和古水流研究显示,其中3组砾石统计表明砾岩层砾石成分主要由火山岩或火山碎屑岩组成,3组古水流数据表明,诸城地区王氏群红土崖组砾岩层的古流向以南和南东方向为主,尚有1组显示古流向为向北,表明王氏群物源主要来自盆地北侧莱阳和北西侧沂沭断裂带的青山群火山岩,其次为盆地南缘。本研究为诸城王氏群化石层沉积时限的限定和沉积物源的判断,以及胶莱盆地王氏群时期古地理格局的恢复等提供了重要的依据。
The large-area and high-density dinosaur fossils buried in the late Cretaceous Wangzhu in Zhucheng, eastern Shandong are the hot topics in recent years. However, the sedimentary provenance and precise deposition time limit are not yet clear. Detrital zircon U-Pb dating of 6 sandstone samples from the dinofossil fossil layer of Wangshi Group in Zhucheng, Shandong Province indicates that the youngest single-grain zircon age (YSG) in sample 090414-24-D is 77.3 Ma and should be The maximum deposition time (lower limit) of the dinosaur fossil layer representing the Wangs group, combined with the predecessors’ study of the Hongtuya Formation of the Wangshi Group, shows that the sedimentary time limit should be older than 73.5 Ma (upper limit) and also indicate the presence of the dinosaur fossil layer The Hongtuya Formation in the upper part of the Wangshi Group is Campanian sedimentary. The detrital zircons reveal that the zircon ages of provenances are distributed between 100 and 130 Ma, and the main peak ages of the six samples are mostly above 110 Ma or 120 Ma , Which coincides with the peak age of volcanic rocks of the Lower Cretaceous Qingshan Group in the Lower Cretaceous. The gravel composition and paleocurrent of the dinosaur fossil layer conglomerate in the Wangsun Group show that gravels in the three gravels show that the gravel layer consists mainly of volcanic rocks or volcaniclastic rocks. The data of three ancient water streams show that the Wang Clan laterite The paleocurrent of the conglomerate layer of the Yaxian Formation is dominated by the south and south east directions, and one group shows that the paleocurrent flow is northward, indicating that the source of the Wangs group mainly comes from the Aoyama Group in Laiyang, north of the basin and Yishu fault in the northwest of the basin Volcanic rocks, followed by the southern margin of the basin. This study provides an important basis for defining the limit of fossil layer deposition and the source of sediments in Zhucheng Wangshi Group and the restoration of palaeogeographical pattern during the Wang Group period in the Jiaolai Basin.