0 an extinct sea creature (= one that no longer exists) often found as a fossil (= an animal turned into rock), with a flat, spiral shell -- 菊石（鸚鵡螺的化石）
No ammonites have been recorded from between -1.8 m to 0 m in the section.
Nektonic taxa such as belemnites and ammonites dominate the fauna, with lesser bivalves and brittle stars found almost exclusively in the coarser units.
Most of the ammonites studied have ribs, tubercles, keels and other ornaments.
Dashed ammonite-zone and bed boundaries reflect some uncertainty of their precise position in the core.
Apart from ammonites and dinoflagellates, very little other stratigraphic data is discussed in detail.
The sudden appearance of these genera represents a major reinvasion of the basin by neocomitid ammonites.
We note, however, that ammonites have not been recorded from the 1.8 m of strata below the proposed boundary level.
This method can therefore be used to compare the morphological signal of ammonites with other physical or chemical signals.
