DOI: 10.1016/j.palaeo.2014.01.010
论文题名: Stable isotope (δ18O and δ13C) sclerochronology of Callovian (Middle Jurassic) bivalves (Gryphaea (Bilobissa) dilobotes) and belemnites (Cylindroteuthis puzosiana) from the Peterborough Member of the Oxford Clay Formation (Cambridgeshire, England): Evidence of palaeoclimate, water depth and belemnite behaviour
作者: Mettam C. ; Johnson A.L.A. ; Nunn E.V. ; Schöne B.R.
刊名: Palaeogeography, Palaeoclimatology, Palaeoecology
ISSN: 0031-0182
出版年: 2014
卷: 399 起始页码: 187
结束页码: 201
语种: 英语
英文关键词: Belemnite
; Gryphaea
; Jurassic
; Oxygen and carbon stable isotopes
; Paleoseasonality
; Sclerochronology
英文摘要: Incremental δ18O and δ13C signals were obtained from three well-preserved specimens of Cylindroteuthis puzosiana and from three well-preserved specimens of Gryphaea (Bilobissa) dilobotes from the Peterborough Member of the Oxford Clay Formation (Cambridgeshire, England). Through-ontogeny (sclerochronological) δ18O data from G. (B.) dilobotes appear to faithfully record seasonal temperature variations in benthic Callovian waters of the study area, which range from c. 14°C to c. 17°C (arithmetic mean temperature c. 15°C). Water depth is estimated to have been in the region of c. 50m, based upon comparisons between these data, previously published non-incremental sea surface δ18O values, and a modern analogue situation. Productivity in Callovian waters was comparable with that in modern seas, based upon δ13C data from G. (B.) dilobotes, with 13C depletion occurring during warmer periods, possibly related to an interaction between plankton blooms and intra-annual variations in mixing across a thermocline. Incremental δ18O data from C. puzosiana provide temperature minima of c. 11°C for all specimens but with maxima varying between c. 14°C and c. 16°C for different individuals (arithmetic mean values c. 13°C). Temperatures for late ontogeny, when the C. puzosiana individuals must have been living close to the study site and hence the analysed specimens of G. (B.) dilobotes, are closely comparable to those indicated by the latter. However, for significant portions of ontogeny C. puzosiana experienced temperatures between c. 2°C and c. 3°C cooler than the winter minimum as recorded by co-occurring G. (B.) dilobotes. Comparisons with modern seas suggest that descent to a depth of c. 1000m would be necessary to explain such cool minimum temperatures. This can be discounted due to the lack of deep waters locally and due to estimates of the depth tolerance of belemnites. The most likely cause of cool δ18O signals from C. puzosiana is a cosmopolitan lifestyle including migration to more northerly latitudes. Mean δ13C values from C. puzosiana are comparable with those from G. (B.) dilobotes. However, the incrementally acquired data are highly variable and probably influenced by metabolic effects. The probable identification of migratory behaviour in C. puzosiana calls into question the reliability of some belemnite species as place-specific palaeoenvironmental archives and highlights the benefits of adopting a sclerochronological approach. © 2014 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/69414
Appears in Collections: 过去全球变化的重建
There are no files associated with this item.
作者单位: Geographical Earth and Environmental Sciences, School of Science, University of Derby, Derby DE22 1GB, United Kingdom; Institute of Geosciences, University of Mainz, 55128 Mainz, Germany
Recommended Citation:
Mettam C.,Johnson A.L.A.,Nunn E.V.,et al. Stable isotope (δ18O and δ13C) sclerochronology of Callovian (Middle Jurassic) bivalves (Gryphaea (Bilobissa) dilobotes) and belemnites (Cylindroteuthis puzosiana) from the Peterborough Member of the Oxford Clay Formation (Cambridgeshire, England): Evidence of palaeoclimate, water depth and belemnite behaviour[J]. Palaeogeography, Palaeoclimatology, Palaeoecology,2014-01-01,399