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贵阳花溪下三叠统大冶组中富产遗迹化石,产出18个遗迹属:Beaconichnus,Circulichnis,Cosmorhaphe,Dendro-haphe,Glockerichnus,Gyrochorte,Gordia,Maeandropolydora,Micatuba,Mammillichnis,Megagrapton,Planolites,Palaeophycus,Phycodes,Phycosiphon,Rhizocorallium,Thalassinoides和Undichna。自下而上可识别出三个遗迹组构,分别为Phycodes、Phycosiphon-Mammillichnis和Thalassinoidess遗迹组构。根据遗迹化石各属种分布,大冶组自下而上出现四个遗迹相:Cruziana遗迹相、Zoophycoss遗迹相、Nereites遗迹相和Cruziana遗迹相。结合遗迹组构,对大冶组的沉积环境进行了讨论,Phycodes组构属于Cruziana相,指示浅水环境;Phycosiphon-Mammillichnis组构属于Zoophycos遗迹相—Nereites遗迹相,代表台缘下斜坡半深海低能环境;Thalassinoides组构属于Cruziana相,指示早三叠世印度期末的浅水高能环境。
18 fossils are found in the Lower Triassic Daye Formation of Huaxi, Guiyang, with 18 genera: Beaconichnus, Circulichnis, Cosmorhaphe, Dendro-haphe, Glockerichnus, Gyrochorte, Gordia, Maeandropolydora, Micatuba, Mammillichnis, Megagrapton, Planolites, Palaeophycus, Phycodes , Phycosiphon, Rhizocorallium, Thalassinoides and Undichna. From the bottom up, three relic structures can be identified: Phycodes, Phycosiphon-Mammillichnis and Thalassinoidess relics. According to the distribution of trace fossils, the Daye Formation has four trace facies from bottom to top: the Cruziana trace facies, the Zoophycoss trace facies, the Nereites trace facies and the Cruziana trace facies. The sedimentary environment of Daye Formation is discussed in combination with the relic structure. The Phycodes structure belongs to the Cruziana facies, which indicates the shallow environment. The Phycosiphon-Mammillichnis assemblage belongs to the Zoophycos relic facies-Nereites facies, which represents the semi-deep low-lying environment Thalassinoides is a member of the Cruziana facies, indicating the shallow-water, high-energy environment of the Early Triassic period in India.