@article{oai:soar-ir.repo.nii.ac.jp:00012016,
 author = {MORIKIYO,  TOSHIRO and MATSUNAGA,  KINUKO and IWAMASA,  KAZUO and KANISAWA,  SATOSHI},
 journal = {信州大学理学部紀要},
 month = {Mar},
 note = {The variations of Fe, Mn and Mg concentrations in pore water were deduced from the chemistry of calcite. With depth, the Fe/Ca, Mn/Ca, Mg/Ca ratios of pore water decrease. The decrease in the Fe/Ca ratio is due to the precipitation of pyrite, whereas the decrease in the Mn/Ca ratio is due to the precipitation of Mn-rich calcite. The depletion of Mg in pore water is ascribed to the precipitation of either Mg-rich smectite or Mg-rich chlorite. A-type rock is further divided into A1 and A2 subtypes, on the basis of δ13C. Excesses of MgO and deficiencies of K舀 O above the calculated whole-rock compositions are observed mainly in the phosphatic nodules and A1 subtype. This suggests that the formation of Mg-rich smectite or Mg-rich chlorite took place at very early stage of diagenesis of the Toyoma Formation., Article, 信州大学理学部紀要 38: 23-34(2004)},
 pages = {23--34},
 title = {Variations of divalent cation concentrations in pore water and the precipitation of Mg-rich authigenic mineral during early diagenesis of Toyoma Formation},
 volume = {38},
 year = {2004}
}