FENG Chen-xu1, DONG Fa-qin1,2*, DAI Qun-wei1,2, HUO Ting-ting1, NELSON Belzile1,3
(1. Environment and Resource College, Southwest University of Science and Technology, Mianyang 621010, China;
2. Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, Mianyang 621010, China;
3. Department of Chemistry and Biochemistry, Laurentian University, Sudbury, Ontario P3E 2C6, Canada)
Abstract: In order to investigate the characteristics and origin of the brown-white intermixed laminated layers in lamina travertine at Huanglong in Sichuan Province, we have collected and analysed samples of lamina travertine in the Huanglong area in this study. The organic carbon contents of travertine samples from different coloured layers have been analysed using a microwave digestion method. The crystal phase, morphology, and contents of elements of samples have been analysed using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Elemental Analysers, and the Mg/Ca ratios of samples have been calculated. The results show that there are obvious differences in the organic carbon contents and Mg/Ca ratios between the brown and white layers of the lamina travertine at Huanglong, as the organic carbon contents and Mg/Ca ratios of brown layers are higher than those of the respectively adjacent white layers. The organic carbon contents of travertine layers are gradually increased with the variation of their deposition sequences from old to young. The brown and white lamina layers in the annual travertine profile are affected not only by microorganisms and plants, but also by different climatic factors, such as temperature and hydrodynamics. This means that the brown and white intermixed layer in the annual travertine profile at Huanglong could a combined biological-climatic genesis. This can provide a certain theoretical basis for finding evidence of biological participation in the deposition process of the Huanglong travertine.
Keywords: travertine; lamina; characteristics; genesis; Huanglong
ACTA MINERALOGICA SINICA Vol. 39, No.1, 2019, page 55-63
