Monday, 29 October 2018

PHYLLOCERAS CONSANGUINEUM

Phylloceras consanguineum (Gemmellaro 1876) a fast-moving carnivorous ammonite from Late Jurassic (Middle Oxfordian) deposits near Sokoja, Madagasgar, off the southeast coast of Africa. (22.8° S, 44.4° E: 28.5° S, 18.2° E)

This classical Tethyan Mediterranean specimen is very well preserved, showing much of his delicate suturing in intricate detail. Phylloceras were primitive ammonites with involute, laterally flattened shells.

They were smooth, with very little ornamentation, which led researchers to think of them resembling plant leaves and gave rise to their name, which means "leaf-horn."

They can be found in three regions that I know of.  In the Jurassic of Italy near western Sicily's Rosso Ammonitico Formation, Lower Kimmeridgian fossiliferous beds of Monte Inici East and Castello Inici (38.0° N, 12.9° E: 26.7° N, 15.4° E) and in the Arimine area, southeastern Toyama Prefecture, northern central Japan, roughly (36.5° N, 137.5° E: 43.6° N, 140.6° E) Dōitashimashite ; )

Saturday, 27 October 2018

RHACOLEPIS BUCCALIS

Rhacolepis Buccalis, an extinct genus of ray-finned fossil fish in carbonate concretion, Lower Cretaceous, Santana Formation, Brazil. These nektonic carnivores swam our ancient seas 122-109 million years ago.

Le premier et unique géoparc mondial UNESCO est situé dans le Cariri du Ceará (géoparc Araripe), dans l'intérieur semi-aride de la région Nordeste, Brésil

Thursday, 25 October 2018

BREWERICERAS HULENENSE

Brewericeras hulenense (Anderson 1938) a fast-moving, nektonic (no idle floating here!) carnivorous ammonite from the Lower Cretaceous (Albian) of Haida Gwaii (aka Queen Charlotte Islands), British Columbia, Canada.

Ammonites belong to the class of animals called mollusks. More specifically they are cephalopods. and first appeared in the lower Devonian Period.

Cephalopods were an abundant and diverse group during the Paleozoic Era. This specimen is just over 12cm in length, a little under the average of 13.4cm. There are several localities in the Queen Charlotte Islands where Brewericeras can be found (six that I know of and likely plenty more!) This specimen was found on a trip a few years back done with the Vancouver Paleontological Society and a few of the members of some of the Island paleo groups. The preservation is quite remarkable!

Brewericeras are also found in Albian deposits in Svedenborgfjellet, Ulladalen, Norway (Cretaceous of Svalbard and Jan Mayen - så fin!) (77.7° N, 15.2° E: paleocoordinates 66.6° N, 13.6° E) and Matanuska-Susitna County, Alaska, 62.0° N, 147.7° W: paleocoordinates 57.3° N, 85.6° W (112.6 to 109.0 Ma.)

Tuesday, 23 October 2018

Friday, 12 October 2018

Friday, 5 October 2018

DACTYLIOCERAS AMMONITE

A lovely Dactylioceras ammonite from the Lower Jurassic Upper Lias Holderness of the Yorkshire Coast. This beauty measures over 8cm with especially attractive colouring.

Holderness is an area of the East Riding of Yorkshire, on the east coast of England. An area of rich agricultural land, Holderness was marshland until it was drained in the Middle Ages. Topographically, Holderness has more in common with the Netherlands than with other parts of Yorkshire. To the north and west are the Yorkshire Wolds.

Geologically, Holderness is underlain by Cretaceous chalk but in most places, it is so deeply buried beneath glacial deposits that it has no influence on the landscape.

The landscape is dominated by deposits of till, boulder clays and glacial lake clays. These were deposited during the Devensian glaciation. The glacial deposits form a more or less continuous lowland plain which has some peat filled depressions (known locally as meres) which mark the presence of former lake beds. There are other glacial landscape features such as drumlin mounds, ridges and kettle holes scattered throughout the area.

The well-drained glacial deposits provide fertile soils that can support intensive arable cultivation. Fields are generally large and bounded by drainage ditches. There is very little woodland in the area and this leads to a landscape that is essentially rural but very flat and exposed. The coast is subject to rapid marine erosion.

The Geology of Yorkshire in northern England shows a very close relationship between the major topographical areas and the geological period in which their rocks were formed. The rocks of the Pennine chain of hills in the west are of Carboniferous origin whilst those of the central vale are Permo-Triassic.

The North York Moors in the northeast of the county are Jurassic in age while the Yorkshire Wolds to the southeast are Cretaceous chalk uplands. The plain of Holderness and the Humberhead levels both owe their present form to the Quaternary ice ages.

The strata become gradually younger from west to east. Much of Yorkshire presents heavily glaciated scenery as few places escaped the direct or indirect impact of the great ice sheets as they first advanced and then retreated during the last ice age. This beauty is in the collection of the deeply awesome Harry Tabiner.