Polymineral nodules from the salt-marl sequence of the Solikamsk depression

Authors

  • Marina Viktorovna Bubnova Mining Institute of the Ural Branch of the Russian Academy of Sciences
  • Ilya Ivanovich Chaikovskiy Mining Institute of the Ural Branch of the Russian Academy of Sciences
  • Elena Pavlovna Chirkova Mining Institute of the Ural Branch of the Russian Academy of Sciences

DOI:

https://doi.org/10.17072/chirvinsky.2022.18

Keywords:

salt-marl strata, concretions, metasomatic differentiation, mineralogical marker of ecological crisis

Abstract

The mineral composition and structure of polymineral nodules, composed of chalcedony in the center, carbonates and sulfates along the periphery, are characterized. Their zoning, the presence of inclusions of miliolid shells, and the absence of encasing structures testify to their metasomatic nature. The evolutionary series of nodules (chalcedony - chalcedony-calcite - chalcedony-calcite-gypsum - chalcedony-gypsum) has been reconstructed, reflecting the differentiation of substances according to their solubility. It has been suggested that the confinement of nodules to the upper part of the salt-marl strata reflects the change in the sedimentation basin of sulfate-calcium waters to bicarbonate-calcium and may mark the level of extinction of organisms that prefer high salinity.

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Published

2022-04-12

How to Cite

Bubnova М. В., Chaikovskiy И. И., & Chirkova Е. П. (2022). Polymineral nodules from the salt-marl sequence of the Solikamsk depression . Problems of Mineralogy, Petrography and Metallogeny. Scientific Readings in Memory of P.N. Chirvinsky, (25), 18–26. https://doi.org/10.17072/chirvinsky.2022.18

Issue

No. 25 (2022): Readings in memory of P.N. Chirvinsky 2022

Section

Статьи