|
| << previous | next >> |
Journal description
All volumes of the corresponding journal
All issues of the corresponding volume
All articles of the corresponding issues
Details for article 163 of 165 found articles
| Title: |
Upper Jurassic and Lower Cretaceous Buchia (Bivalvia) from southern Tibet, and some wider considerations |
| Author: |
Grant-Mackie, J. A. |
| Appeared in: |
Alcheringa |
| Paging: | Volume 12 (1988) nr. 4 pages 249-268 |
| Year: |
1988 |
| Contents: |
Three different assemblages of Buchia species are recorded from fine elastics in the Nyalam district of southern Tibet. Praebuchia, Buchia spitiensis and B. concentrica (upper Oxfordian-Kimmeridgian) occur in the Menbu Formation; B. rugosa, B. piochii etc. (Tithonian) characterise the Shuomo Formation; B. shuomoensis, B. mankamanensis etc. (Lower Cretaceous) occur in the Guchuochun Formation. These assemblages correspond with a worldwide pattern of initial development, acme and then decline evident in the genus, whose distribution clearly shows a southwards migration pattern, with extinction operating in the opposite direction. Although regarded as of shallow water origin in some areas, in the central Tethys Buchia appears in deeper water strata and this is correlated with preference for cooler temperatures; its extinction could thus have been due to the postulated terminal Jurassic regression. |
| Publisher: |
Taylor & Francis |
| Source file: |
Elektronische Wetenschappelijke Tijdschriften |
Details for article 163 of 165 found articles
| << previous | next >> |