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Shannon Entropy as an Indicator for Sorting Processes in Hydrothermal Systems.

ABSTRACT: Hydrothermal processes modify the chemical and mineralogical composition of rock. We studied and quantified the effects of hydrothermal processes on the composition of volcanic rocks by a novel application of the Shannon entropy, which is a measure of uncertainty and commonly applied in information theory. We show here that the Shannon entropies calculated on major elemental chemical composition data and short-wave infrared (SWIR) reflectance spectra of hydrothermally altered rocks are lower than unaltered rocks with a comparable primary composition. The lowering of the Shannon entropy indicates chemical and spectral sorting during hydrothermal alteration of rocks. The hydrothermal processes described in this study present a natural mechanism for transforming energy from heat to increased order in rock. The increased order is manifest as the increased sorting of chemical elements and SWIR absorption features of the rock, and can be measured and quantified by the Shannon entropy. The results are useful for the study of hydrothermal mineral deposits, early life environments and the effects of hydrothermal processes on rocks.

SUBMITTER: van Ruitenbeek FJA

PROVIDER: S-EPMC7517191 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Shannon Entropy as an Indicator for Sorting Processes in Hydrothermal Systems.

van Ruitenbeek Frank J A FJA Goseling Jasper J Bakker Wim H WH Hein Kim A A KAA

Entropy (Basel, Switzerland) 20200613 6

Hydrothermal processes modify the chemical and mineralogical composition of rock. We studied and quantified the effects of hydrothermal processes on the composition of volcanic rocks by a novel application of the Shannon entropy, which is a measure of uncertainty and commonly applied in information theory. We show here that the Shannon entropies calculated on major elemental chemical composition data and short-wave infrared (SWIR) reflectance spectra of hydrothermally altered rocks are lower tha ...[more]

PMID: 33286427

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Dataset Information

Shannon Entropy as an Indicator for Sorting Processes in Hydrothermal Systems.

Publications

Shannon Entropy as an Indicator for Sorting Processes in Hydrothermal Systems.

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