TY - JOUR

T1 - Onshore mud volcanoes as a geological source of mercury

T2 - Case study from the Kerch Peninsula, Caucasus continental collision zone

AU - Kokh, Svetlana N.

AU - Sokol, Ella V.

AU - Gustaytis, Maria A.

AU - Sokol, Ivan A.

AU - Deviatiiarova, Anna S.

N1 - Publisher Copyright: © 2020 Elsevier B.V. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2021/1/10

Y1 - 2021/1/10

N2 - Three mud volcanoes (MVs) in the Kerch Peninsula were studied as a geological source of mercury. The study focused on total mercury (THg) concentrations in MV waters, mud masses and plants colonizing MV areas; gaseous elemental mercury (GEM) in the atmosphere above MVs; and sulfide mercury (HgS) and HgCl2 species in representative samples of mud masses. THg concentrations in the illite-smectite mud masses ranged from 38 to 920 ng/g. They contained up to 70% of total mercury in sulfide form (in pyrite and cinnabar), but lacked HgCl2. THg values in MV waters of HCO3-Cl/Na- and/or Cl-HCO3/Na-types with рН = 7.4–9.5 mostly fell in a range of 79–440 ng/L, but rarely exceeded 600 ng/L, being comparable with those for geothermal systems. Another issue of interest was the distribution of THg in below- and above-ground parts of halophyte plant Limonium caspium. THg was incorporated into the plant roots, leaves and flowers; the roots exhibited higher concentrations of THg relative to the other organs. The Hg bioaccumulation factor ranged from 0.06 to 0.76. GEM concentrations measured over large bubbling MV pools and newly formed cracks showed values (50 to 520 ng·m−3) higher than background values (≤3 ng·m−3) associated with pristine test sites and background values measured within three MV areas of the Kerch peninsula that is slightly higher than background concentration for the Northern Hemisphere. Maximum GEM contents were comparable with the values found in geothermal and magmatic volcanic provinces.

AB - Three mud volcanoes (MVs) in the Kerch Peninsula were studied as a geological source of mercury. The study focused on total mercury (THg) concentrations in MV waters, mud masses and plants colonizing MV areas; gaseous elemental mercury (GEM) in the atmosphere above MVs; and sulfide mercury (HgS) and HgCl2 species in representative samples of mud masses. THg concentrations in the illite-smectite mud masses ranged from 38 to 920 ng/g. They contained up to 70% of total mercury in sulfide form (in pyrite and cinnabar), but lacked HgCl2. THg values in MV waters of HCO3-Cl/Na- and/or Cl-HCO3/Na-types with рН = 7.4–9.5 mostly fell in a range of 79–440 ng/L, but rarely exceeded 600 ng/L, being comparable with those for geothermal systems. Another issue of interest was the distribution of THg in below- and above-ground parts of halophyte plant Limonium caspium. THg was incorporated into the plant roots, leaves and flowers; the roots exhibited higher concentrations of THg relative to the other organs. The Hg bioaccumulation factor ranged from 0.06 to 0.76. GEM concentrations measured over large bubbling MV pools and newly formed cracks showed values (50 to 520 ng·m−3) higher than background values (≤3 ng·m−3) associated with pristine test sites and background values measured within three MV areas of the Kerch peninsula that is slightly higher than background concentration for the Northern Hemisphere. Maximum GEM contents were comparable with the values found in geothermal and magmatic volcanic provinces.

KW - Cinnabar

KW - Gaseous elemental mercury

KW - Halophyte plant

KW - Pyrite

KW - Sulfide mercury

KW - Total mercury

KW - CLAY-MINERALS

KW - EMISSIONS

KW - HALIMIONE-PORTULACOIDES

KW - NATURAL SOURCES

KW - SALT-MARSH PLANT

KW - TAMAN RUSSIA

KW - SPECIATION

KW - ATMOSPHERIC MERCURY

KW - CHLORIDE CONCENTRATION

KW - WATER

UR - http://www.scopus.com/inward/record.url?scp=85090206521&partnerID=8YFLogxK

U2 - 10.1016/j.scitotenv.2020.141806

DO - 10.1016/j.scitotenv.2020.141806

M3 - Article

C2 - 32882564

AN - SCOPUS:85090206521

VL - 751

SP - 141806

JO - Science of the Total Environment

JF - Science of the Total Environment

SN - 0048-9697

M1 - 141806

ER -