OXYGEN-ISOTOPE COMPOSITION OF PALYGORSKIT ES FROM CALCRETE PROFILES -CONDITIONS OF FORMATION

Authors
GAUTHIERLAFAYE F TAIEB R PAQUET H CHAHI A PRUDENCIO I BRAGA MAS
Citation
F. Gauthierlafaye et al., OXYGEN-ISOTOPE COMPOSITION OF PALYGORSKIT ES FROM CALCRETE PROFILES -CONDITIONS OF FORMATION, Comptes rendus de l'Academie des sciences. Serie 2, Mecanique, physique, chimie, sciences de l'univers, sciences de la terre, 316(9), 1993, pp. 1239-1245
Citations number
21
Categorie Soggetti
Multidisciplinary Sciences
Journal title
Comptes rendus de l'Academie des sciences. Serie 2, Mecanique, physique, chimie, sciences de l'univers, sciences de la terre → ACNP
ISSN journal
07644450
Volume
316
Issue
9
Year of publication
1993
Pages
1239 - 1245
Database
ISI
SICI code
0764-4450(1993)316:9<1239:OCOPEF>2.0.ZU;2-J
Abstract
Isotopic compositions of oxygen of palygorskites, enriched in O-18(del taO-18: +33 to +34 parts per thousand SMOW) and of oxygen and carbon o f calcites associated to calcretes from Portugal and Morocco show stro ng evidence that evaporation of meteoritic water is an important proce ss for the crystallization of these minerals. In semi-arid climates, a s in Portugal, palygorskites crystallize when evaporation is maximum d uring the dry seasons whereas calcites precipitate during more humid p eriods.