Open AccessThe isotopic composition of oxygen and carbon in the subfossil mollusc shells of the Baltic Sea as an indicator of palaeosalinity
Author(s) -
PUNNING JAANMATI,
MARTMA TÖNU,
KESSEL HELGI,
VAIKMÄE REIN
Publication year - 1988
Publication title -
boreas
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.95
H-Index - 74
eISSN - 1502-3885
pISSN - 0300-9483
DOI - 10.1111/j.1502-3885.1988.tb00120.x
Subject(s) - subfossil , carbonate , salinity , geology , seawater , littorina , oceanography , mineralogy , environmental chemistry , paleontology , holocene , gastropoda , chemistry , organic chemistry
The carbon (δ 13 C) and oxygen (δ 18 O) isotopic composistion in mollusc shells in mainly determined by the isotopic composition of water and dissolved bicarbonate. The δ 18 O values of water show a good correlation with the salinity of the Baltic. This correlation served as a basis for reconstructing palaeosalinity and for stratifying the marine sediments according to the δ 18 O values of the carbonate skeletons of subfossil shells. The δ 13 C values in shells are mainly determined by the isotopic composition of land‐originating bicarbonate, especially in the carbonate skeleton of Lymnaea balthica , which inhabits the immediate coastal zone. According to the δ 18 O data, salinity in the investigated area (the coastal area of W and NW Estonia) was highest (about 9–11%) during the Littorina stage. The Limnae a stage had, in general, a salinity similar to the contemporary one, but during some phases possibly exceeding it by 2–3%.