1,721,052 research outputs found
La flora del Giurassico dell'Italia settentrionale. The Jurassic flora of northern Italy
No full textLate Carboniferous floras from the Southern Alps, Tuscany and Sardinia (Italy): a state of the art on the main outcrops and historical collections.
No full textThe Jurassic plant fossils of the Lovisato Collection: preliminary notes
No full textA preliminary account is presented herein of the revision of 473 slabs containing macrofossil plant remains from the Domenico Lovisato plant Collection. The latter is housed in the Museo Sardo di Geologia e Paleontologia “D. Lovisato” of the Università di Cagliari. The material examined encompasses palaeobotanical remains collected from the Genna Selole Formation and from the basal part of the Dorgali Formation, both of Jurassic age at a variety of localities in Barbagia and Sarcidano, eastern Sardinia. A reconstruction is given of the history of the collection, initiated in 1888, and the scientific studies of the flora by a variety of palaeobotanists. Based on a preliminary revision of the specimens the following genera are recognized: Phlebopteris Brongniart, 1836, Hausmannia Dunker, 1846, Coniopteris Brongniart, 1849, Cladophlebis Brongniart, 1849, Sagenopteris Presl in Sternberg, 1838, Cycadeospermum Saporta, 1875, Ptilophyllum Morris in Grant, 1840, Williamsonia Carruthers, 1870 emend. Harris, 1969, Weltrichia Braun, 1847 emend. Harris, 1969, Taeniopteris Brongniart, 1828, Czekanowskia Heer, 1876 emend. Harris et al., 1974, Brachyphyllum Brongniart, 1828, Elatocladus Halle, 1913 emend. Harris, 1979 and Carpolithes Brongniart, 1822. Some plant remains have been putatively assigned to the following genera: Ptilozamites Nathorst, 1878 emend. Antevs, 1914, Nilssonia Brongniart, 1825, Pterophyllum Brongniart, 1828 and Geinitzia Endlicher, 1847. Several of these genera are known also from the Jurassic flora of Yorkshire and from other Jurassic floras of Italy
Triassic climates - State of the art and perspectives
No full textThe climate of the Triassic period was characterized by a non-zonal pattern, dictated by a strong global
monsoon system with effects that are most evident in the Tethys realm. This strong monsoonal regime is
related to the aggregation of the Pangaean supercontinent, which by Triassic time was already completed.
Climate oscillations existed within this framework. The harsh hot-house climatic conditions that
characterized the Late Permian, and perhaps precipitated the end-Permian mass extinction, were probably
maintained during the Early Triassic and may account for the impoverished, but distinctive, faunal and floral
Lower Triassic associations. Although metazoan reef builders were probably the most affected group,
carbonate production remained high at least in the western Tethys realm. The Middle Triassic was
characterized locally by humid episodes, although their geographical distribution has yet to be clarified. The
Carnian Pluvial Event, marks an episode of increased rainfall documented worldwide, was the most
distinctive climate change within the Triassic. Different hypotheses have been proposed for its causes:
changes of atmospheric or ocean circulation driven by plate tectonics; a peak of the global monsoon due to
maximum continent aggregation; or triggering by the eruption of a large igneous province. Subsequently, the
late Carnian and Norian seem to have been climatically stable, although minor climatic changes have
recently been described even from this time period. Finally, the end-Triassic extinction event is also
associated with climate change, specifically warming and increased rainfall, but this evidence comes mostly
from the northern parts of the Central Atlantic Magmatic Province, and the global pattern of climate change
at the Triassic/Jurassic boundary has still to be resolved. Many facets of Triassic climate are intriguing and
deserve further research. However, palaeoclimate studies on the Triassic have so far been carried out only
locally with different proxies. Those proxies will require inter-calibration, in order to depict correctly the
temporal and geographical patterns of Triassic climate
The Jurassic flora of Sardinia - A new piece in the palaeogeographic puzzle of the Middle Jurassic
No full textThe Middle Jurassic flora of Sardinia has been studied, and 24 taxa (19 genera) belonging to horsetails,
ferns (Phlebopteris, Hausmannia, Coniopteris, Todites, Cladophlebis), seed ferns (Sagenopteris, Ptilozamites),
cycadophytes (Nilssonia, Pterophyllum, Cycadeospermum, Ptilophyllum, Williamsonia, Weltrichia, Taeniopteris),
ginkgophytes (Czekanowskia), conifers (Geinitzia, Brachyphyllum, Elatocladus) and seeds (Carpolithes), have
been identified. The flora of Sardinia is the southernmost of all Middle Jurassic European floras. The coeval
European and North African floral assemblages (112 genera) are present in a wide variety of environments
and different palaeogeographic positions, which is reflected in a wide variety of taxa. A comparison between
the coeval floras of Middle Jurassic age reveals a higher degree of dissimilarity than similarity between the various
assemblages, which is in disagreement with the general picture of the homogeneity in the Jurassic floras
given by previous authors
Pennsylvanian floras from Italy: an overview of the main sites and historical collections
No full textThe paper provides an overview of the main Pennsylvanian sites in Italy yielding associations rich in plants and/or
palynomorphs. So far in Italy, the principal outcrops are located in the Southern Alps, Tuscany and Sardinia. In the
Western Southern Alps and bordering Switzerland, Westphalian outcrops are small and scattered. Nevertheless, one
of them yielded an abundant fossil flora, stored at the Museo Civico di Storia Naturale of Milan, (Venzo and Maglia
Collection). In the Carnic Alps, (Eastern Southern Alps), continental deposits of Moscovian to Gzhelian age also occur
near the border with Austria. They have produced a high number of preserved plant fossils, presently stored in
the Museo Friulano di Storia Naturale of Udine. In Tuscany, the two main sections yielding Westphalian to Autunian
floras are those of the Iano and Pisani Mountains. A rich collection of plant fossils from those sites is hosted at the
Museo di Storia Naturale of Florence University and at the Museum of Natural History of Pisa University. In Sardinia,
plant fossil sites are located in the south west and central east parts of the island. The San Giorgio Basin (Iglesiente
subregion) and the Tuppa Niedda section (Arburese subregion) are late Westphalian – early Stephanian in age.
In the Barbagia at SeuiSeulo
and the Gerrei subregions, other continental basins yielded transitional “StephanianAutunian”
fossil plant associations. The slabs are stored as part of the Lovisato Collection at the Lovisato Museum
of the Chemical and Geoscience Department of Cagliari University. Smaller historical outcrops of Carboniferous age
are also known from other Italian regions, such as Liguria
- …
