Geochemistry and molybdenum isotopes of the basal Datangpo Formation: Implications for ocean-redox conditions and organic matter accumulation during the Cryogenian interglaciation

Carbon Isotope Reversal Gas Generated in the Hydrothermal Experiments Involving 1-MNa and MnCO3

“…Essentially, Mn-bearing minerals have been widely found in geological settings (i.e., organic-rich shale). It is observed that sediments imported by hydrothermal solution tend to be enriched in Mn. − Considering the actual natural conditions, high contents of MnCO 3 are often present near oil and gas reservoirs . In basins with favorable conditions for the formation of other inorganic minerals, a similar effect as that of rhodochrosite–water–OM to alkane natural gas may occur.…”

“…56−58 Considering the actual natural conditions, high contents of MnCO 3 are often present near oil and gas reservoirs. 29 In basins with favorable conditions for the formation of other inorganic minerals, a similar effect as that of rhodochrosite− water−OM to alkane natural gas may occur. The synergistic effect of inorganic minerals, water, and OM may be a new reason for the formation of isotope reversal natural gas, in particular geological settings (i.e., with MnCO 3 deposit).…”

“…Manganese (Mn) is also an important transition-metal element with a considerable content in the sedimentary strata. Mn-bearing minerals are widely distributed in the Carboniferous, Permian, Triassic, and other geological strata where oil and gas are generated and discovered. − For instance, enriched rhodochrosite (MnCO 3 ) has been found in some basins with superior source rocks. , In MnCO 3 -bearing member of the Datangpo Formation in South China, Mn content is positive with the TOC content and can reach 10–30% . Transition metal Mn is a common reactive element with various valence states and good catalytic properties.…”

“…26−28 For instance, enriched rhodochrosite (MnCO 3 ) has been found in some basins with superior source rocks. 5,29 In MnCO 3 -bearing member of the Datangpo Formation in South China, Mn content is positive with the TOC content and can reach 10−30%. 29 Transition metal Mn is a common reactive element with various valence states and good catalytic properties.…”

“…5,29 In MnCO 3 -bearing member of the Datangpo Formation in South China, Mn content is positive with the TOC content and can reach 10−30%. 29 Transition metal Mn is a common reactive element with various valence states and good catalytic properties. Mn-bearing minerals with high valence (i.e., MnO 2 ) could oxidize hydrocarbons including methane at 90−135 °C in particular reservoirs.…”