|mhorn||Дата: Friday, 05.07.2013, 23:42 | Сообщение # 1|
|Bardin J., Rouget I. & Cecca F. (2013) Late Pliensbachian (Early Jurassic) ammonites from Lac de Charmes (Haute-Marne, France): Systematic, biostratigraphy and palaeobiogeography // Geodiversitas 35 (2): 309-334. http://dx.doi.org/10.5252/g2013n2a2 |
The present paper deals with the systematic description of a rich and well-preserved ammonite fauna of the Late Pliensbachian, collected in two outcrops near the “Lac de Charmes” (Haute-Marne, France). In terms of ammonite zonation, the studied faunas indicate the Margaritatus and Spinatum Chronozones. Most of their subdivisions (subchronozones and zonules) have been recognized for the ﬁrst time in this region. We propose a correlation with zonations established in close areas (Germany, Southern France). As already suggested on the literature, the possibility to further subdivide the Solare zonule in ﬁnner intervals is conﬁrmed by our data. Within this zonule, we recognize a ﬁrst interval with only Pleuroceras solare (Phillips, 1829), and a second one where this species occurs with several subspecies and where Pleuroceras spinatum (Bruguière, 1789) appears. Our results also conﬁrm the possibility to subdivide more ﬁnely the Solare zonule ﬁrstly suggested by some authors. We recognize a ﬁrst part with only Pleuroceras solare and a second one where this species present various subspecies and where Pleuroceras spinatum appears. Some points of view are given about Amaltheus gr. margaritatus Montfort, 1808, Pleuroceras gr. solare (Phillips, 1829) and the species Pleuroceras transiens (Frentzen, 1934).
Middle Jurassic - Lower Cretaceous ammonites & aptychi