On changing trends of delta D during seawater freezing and evaporation

Citation
Yq. Wang et al., On changing trends of delta D during seawater freezing and evaporation, COLD REG SC, 31(1), 2000, pp. 27-31
Citations number
13
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Civil Engineering
Journal title
COLD REGIONS SCIENCE AND TECHNOLOGY
ISSN journal
0165-232X → ACNP
Volume
31
Issue
1
Year of publication
2000
Pages
27 - 31
Database
ISI
SICI code
0165-232X(200002)31:1<27:OCTODD>2.0.ZU;2-H
Abstract
Subsurface brines can be formed by both evaporation and freezing. The ratio of Na+/Cl- (eq.) of brines in polar region is so low (about 0.2) that it b ecomes a criterion for identifying brines formed by freezing. However, in o ther areas, the ions in subsurface brines have been exchanged with those of the surrounding matrices for more than ten thousand years making the Na+/C l- ratio useless as an indication of freezing. One-dimensional model tests were conducted to determine the effect of freezing and evaporating seawater on the formation of brines. The results show a delta D-F trend in the resi dual brines formed by freezing is the opposite of those formed by evaporati on delta D-E. Due to the long-term stability of hydrogen isotopes undergrou nd, the authors propose that the brines were formed by freezing if their de lta D are much lower than that of nearby seawater; and were formed by evapo ration if their delta D are higher than that of nearby seawater. (C) 2000 E lsevier Science B.V. All rights reserved.