Ichnology and biostratigraphic significance of Cambrian trace fossils from the lowest stratigraphic level of Kunzam La Formation, Chandra Valley, Lahaul and Spiti, India
R. Kaur, B. Singh, O. Bhargava, R. Mikuláš, Garry Singla, S. K. Prasad, Stanzin Stopden
{"title":"Ichnology and biostratigraphic significance of Cambrian trace fossils from the lowest stratigraphic level of Kunzam La Formation, Chandra Valley, Lahaul and Spiti, India","authors":"R. Kaur, B. Singh, O. Bhargava, R. Mikuláš, Garry Singla, S. K. Prasad, Stanzin Stopden","doi":"10.1080/10420940.2021.1932490","DOIUrl":null,"url":null,"abstract":"Abstract Trace fossils are abundant in the Cambrian Kunzam La Formation in the Lahaul and Spiti regions of the Himalaya. All previously known records belong stratigraphically to the upper part of the Cambrian Series 2/Stage 4 to the Miaolingian Series. In the present work, 15 ichnogenera comprising 26 recorded ichnospecies come from the lower part of the Kunzam La Formation exposed in the Chandra Valley, eastern Lahaul and Spiti, Himachal Pradesh. Three trace fossils associations, based on their sequence of appearance, are: (i) the Treptichnus pedum association (trace fossil association–I)-, a low diversity association, containing Planolites beverleyensis, Palaeophycus isp., and Treptichnus pedum, (ii) the Monomorphichnus association (trace fossil association–II) characterized by a sudden increase in trace fossil diversity and traces of arthropod/trilobite origin comprising Cruziana problematica, Cruziana isp., Catenichnus contentus,? Diplocraterion isp., Dimorphichnus obliquus, Dactylophycus isp., Lockeia siliquaria, Monomorphichnus multilineatus, M. lineatus, Planolites annularis, P. montanus, P. beverleyensis, Palaeophycus imbricatus, P. tubularis, Rusophycus didymus, R. leifeirikssoni, R. dispar, Rusophycus isp., Saerichnites abruptus, and serially repeated Rusophycus and Cruziana, Treptichnus pollardi and arthropod resting traces, and (iii) the Psammichnites association (trace fossil association–III) characterized by a dominant presence of large burrowing systems of Psammichnites gigas and traces of Diplichnites isp. and Ctenopholeus kutcheri. Considering the same rate of sedimentation for these deposits determined in the >50 km distant Parahio Valley and the stratigraphic position of the Psammichnites gigas assemblage zone in the Himalaya, these trace fossil associations probably fall within Cambrian Series 2, Stage 4, though the sudden increase in diversity and complexities of traces suggest an older age. Stratigraphically, the trace fossils presently described are the oldest yet recorded from the Cambrian of the Lahaul and Spiti regions.","PeriodicalId":51057,"journal":{"name":"Ichnos-An International Journal for Plant and Animal Traces","volume":null,"pages":null},"PeriodicalIF":0.8000,"publicationDate":"2021-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"3","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Ichnos-An International Journal for Plant and Animal Traces","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.1080/10420940.2021.1932490","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"PALEONTOLOGY","Score":null,"Total":0}
引用次数: 3
Abstract
Abstract Trace fossils are abundant in the Cambrian Kunzam La Formation in the Lahaul and Spiti regions of the Himalaya. All previously known records belong stratigraphically to the upper part of the Cambrian Series 2/Stage 4 to the Miaolingian Series. In the present work, 15 ichnogenera comprising 26 recorded ichnospecies come from the lower part of the Kunzam La Formation exposed in the Chandra Valley, eastern Lahaul and Spiti, Himachal Pradesh. Three trace fossils associations, based on their sequence of appearance, are: (i) the Treptichnus pedum association (trace fossil association–I)-, a low diversity association, containing Planolites beverleyensis, Palaeophycus isp., and Treptichnus pedum, (ii) the Monomorphichnus association (trace fossil association–II) characterized by a sudden increase in trace fossil diversity and traces of arthropod/trilobite origin comprising Cruziana problematica, Cruziana isp., Catenichnus contentus,? Diplocraterion isp., Dimorphichnus obliquus, Dactylophycus isp., Lockeia siliquaria, Monomorphichnus multilineatus, M. lineatus, Planolites annularis, P. montanus, P. beverleyensis, Palaeophycus imbricatus, P. tubularis, Rusophycus didymus, R. leifeirikssoni, R. dispar, Rusophycus isp., Saerichnites abruptus, and serially repeated Rusophycus and Cruziana, Treptichnus pollardi and arthropod resting traces, and (iii) the Psammichnites association (trace fossil association–III) characterized by a dominant presence of large burrowing systems of Psammichnites gigas and traces of Diplichnites isp. and Ctenopholeus kutcheri. Considering the same rate of sedimentation for these deposits determined in the >50 km distant Parahio Valley and the stratigraphic position of the Psammichnites gigas assemblage zone in the Himalaya, these trace fossil associations probably fall within Cambrian Series 2, Stage 4, though the sudden increase in diversity and complexities of traces suggest an older age. Stratigraphically, the trace fossils presently described are the oldest yet recorded from the Cambrian of the Lahaul and Spiti regions.
期刊介绍:
The foremost aim of Ichnos is to promote excellence in ichnologic research. Primary emphases center upon the ethologic and ecologic significance of tracemaking organisms; organism-substrate interrelationships; and the role of biogenic processes in environmental reconstruction, sediment dynamics, sequence or event stratigraphy, biogeochemistry, and sedimentary diagenesis. Each contribution rests upon a firm taxonomic foundation, although papers dealing solely with systematics and nomenclature may have less priority than those dealing with conceptual and interpretive aspects of ichnology. Contributions from biologists and geologists are equally welcome.
The format for Ichnos is designed to accommodate several types of manuscripts, including Research Articles (comprehensive articles dealing with original, fundamental research in ichnology), and Short Communications (short, succinct papers treating certain aspects of the history of ichnology, book reviews, news and notes, or invited comments dealing with current or contentious issues). The large page size and two-column format lend flexibility to the design of tables and illustrations. Thorough but timely reviews and rapid publication of manuscripts are integral parts of the process.