Zircon U-Pb-Hf isotopes, bulk-rock geochemistry and petrogenesis of Middle to Late Triassic I-type granitoids in the Xing'an Block, northeast China: Implications for early Mesozoic tectonic evolution of the central Great Xing'an Range
Yang H.,Jilin University |
Ge W.-C.,Jilin University |
Yu Q.,Jilin University |
Ji Z.,Jilin University |
And 3 more authors.
Journal of Asian Earth Sciences | Year: 2016
We report zircon U-Pb age data, Hf isotopes, and bulk-rock geochemical data for the Middle to Late Triassic granitoids in the Taerqi-Chabaqi-Kutihe region within the Xing'an Block of the central Great Xing'an Range, northeast China. Euhedral to subhedral zircon grains were extracted from the nine representative granitoids. These zircons exhibit oscillatory zoning typical of a magmatic origin. The zircon U-Pb determinations on the monzogranite, syenogranite and quartz diorite samples yielded ages between 244Ma and 206Ma, which essentially suggests that the magmatism in the Xing'an Block occurred during the Middle to Late Triassic period. Geochemically, these granitoids have SiO2=62.97-76.31wt%, A/CNK=1.03-1.51, and K2O/Na2O=0.40-2.39, we infer that they belong to high-K calc-alkaline series and are peraluminous I-type granites in nature. The major and trace element systematics indicate that these granitoids have different origins. Among them, the 244Ma syenogranite of Taerqi and the 230-206Ma monzogranite and syenogranite of Kutihe were probably generated from partial melting of pre-existing juvenile arc-type rocks in a relatively shallow crustal level. The 210Ma quartz diorite of Chabaqi likely originated from the hybridization between a depleted mantle component and the juvenile subducted oceanic crustal materials that were buried to depths of the middle to lower continental crust. The 212Ma monzogranite and syenogranite of Kutihe were probably generated from the partial melting of miscellaneous lower crustal materials at high pressure conditions. By combining these new data with regional geological data, we conclude that the early Mesozoic evolution of the central Great Xing'an Range was governed by two superimposed tectonic regimes, i.e., (1) post-orogenic extension due to slab break-off after the closure of the Paleo-Asian oceanic basin along the Hegenshan-Heihe suture belt, and (2) back-arc extension associated with the southward subduction of Mongol-Okhotsk oceanic plate. © 2016 Elsevier Ltd. Source
Zhao J.,Jilin University |
Lu W.,Jilin University |
Zhang F.,Jilin University |
Lu C.,Jilin University |
And 3 more authors.
Marine Pollution Bulletin | Year: 2014
Evaluation of CO2 solubility-trapping and mineral-trapping by microbial-mediated process was investigated by lab experiments in this study. The results verified that microbes could adapt and keep relatively high activity under extreme subsurface environment (pH<5, temperature>50°C, salinity>1.0mol/L). When microbes mediated in the CO2-brine-sandstone interaction, the CO2 solubility-trapping was enhanced. The more biomass of microbe added, the more amount of CO2 dissolved and trapped into the water. Consequently, the corrosion of feldspars and clay minerals such as chlorite was improved in relative short-term CO2-brine-sandstone interaction, providing a favorable condition for CO2 mineral-trapping. Through SEM images and EDS analyses, secondary minerals such as transition-state calcite and crystal siderite were observed, further indicating that the microbes played a positive role in CO2 mineral trapping. As such, bioaugmentation of indigenous microbes would be a promising technology to enhance the CO2 capture and storage in such deep saline aquifer like Erdos, China. © 2014 Elsevier Ltd. Source