Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
CARBON ISOTOPIC EVIDENCE FOR PHOTOSYNTHESIS IN EARLY CAMBRIAN OCEANS
Autore:
SURGE DM; SAVARESE M; DODD JR; LOHMANN KC;
Indirizzi:
UNIV ARIZONA,DEPT GEOSCI TUCSON AZ 85721 INDIANA UNIV,DEPT GEOL SCI BLOOMINGTON IN 47405 UNIV MICHIGAN,DEPT GEOL SCI ANN ARBOR MI 48109
Titolo Testata:
Geology
fascicolo: 6, volume: 25, anno: 1997,
pagine: 503 - 506
SICI:
0091-7613(1997)25:6<503:CIEFPI>2.0.ZU;2-T
Fonte:
ISI
Lingua:
ENG
Soggetto:
STABLE-ISOTOPE; FORAMINIFERA; SYMBIOSIS; EVOLUTION; CEMENTS; REEFS;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
36
Recensione:
Indirizzi per estratti:
Citazione:
D.M. Surge et al., "CARBON ISOTOPIC EVIDENCE FOR PHOTOSYNTHESIS IN EARLY CAMBRIAN OCEANS", Geology, 25(6), 1997, pp. 503-506

Abstract

Were the first metazoan reefs ecologically similar to modern tropicalreefs, enabling them to persist under oligotrophic conditions? We tested the hypothesis of ecological similarity by employing a geochemicalapproach. Petrography, cathodoluminescence, trace elements, and stable isotope analyses of primary precipitates of the Lower Cambrian Ajar Limestone, South Australia, indicate preservation of original C isotopic composition. All primary carbonate components exhibit C isotopic values similar to the composition of inorganically precipitated fibrous marine cements, suggesting that archaeocyaths and the calcimicrobe Epiphyton precipitated skeletal carbonate in equilibrium with ambient seawater in the absence of vital effects. Such data do not support the contention that archaeocyaths possessed photosymbionts. However, a +0.5 parts per thousand shift in delta(13)C occurs in reefs developed undershallower-water conditions relative to deeper reefs. This shift suggests the stratification of primary production in Early Cambrian oceans. The pattern is similar to that seen in the modern ocean, whereby significant photosynthesis modulates the C isotopic composition of the photic zone.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 03/12/20 alle ore 16:06:15