The distribution pattern of Helicosphaera inversa (Gartner) Theodoridis is examined from a mid-latitude North Atlantic core (MD01-2446) and two Mediterranean cores (Ocean Drilling Program-ODP Site 975 and Core KC01B) throughMarine Isotope Stage (MIS) 13 to 9. The earliest rare occurrences are observed from the uppermost part of MIS 12, while common and continuous abundances characterize MIS 11. The paleoenvironmental framework of the study cores suggests that the taxon thrived in warm surface waters. Correlation with new data fromplanktonic foraminifera also suggests that H. inversa may have only flourishedwithin a limited salinity range. Comparison with previous findings highlights major diachrony in the FO of the taxon between low and mid-latitude records. It first occurred at lower latitude in the Pacific as early as 0.8 Ma, while in the mid-latitude North Atlantic regions, it is not recorded before 0.51 Ma. The distribution of the taxon in the North Atlantic Ocean also apparently varies in relation with surface water masses and hydrographic fronts. The results suggest that the FO of H. inversa is ecologically controlled and needs to be used with caution in worldwide stratigraphic correlation.Nevertheless, the distribution of the specieswithin theMediterranean Basin can produce an invaluable ecostratigraphical signal.

A paleoecological and paleobiogeographic evaluation of Helicosphaera inversa (Gartner) Theodoridis and the diachrony of its First Occurrence

MAIORANO, Patrizia;MARINO, Maria;GIRONE, ANGELA
2013-01-01

Abstract

The distribution pattern of Helicosphaera inversa (Gartner) Theodoridis is examined from a mid-latitude North Atlantic core (MD01-2446) and two Mediterranean cores (Ocean Drilling Program-ODP Site 975 and Core KC01B) throughMarine Isotope Stage (MIS) 13 to 9. The earliest rare occurrences are observed from the uppermost part of MIS 12, while common and continuous abundances characterize MIS 11. The paleoenvironmental framework of the study cores suggests that the taxon thrived in warm surface waters. Correlation with new data fromplanktonic foraminifera also suggests that H. inversa may have only flourishedwithin a limited salinity range. Comparison with previous findings highlights major diachrony in the FO of the taxon between low and mid-latitude records. It first occurred at lower latitude in the Pacific as early as 0.8 Ma, while in the mid-latitude North Atlantic regions, it is not recorded before 0.51 Ma. The distribution of the taxon in the North Atlantic Ocean also apparently varies in relation with surface water masses and hydrographic fronts. The results suggest that the FO of H. inversa is ecologically controlled and needs to be used with caution in worldwide stratigraphic correlation.Nevertheless, the distribution of the specieswithin theMediterranean Basin can produce an invaluable ecostratigraphical signal.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11586/129270
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 10
  • ???jsp.display-item.citation.isi??? 10
social impact