Jurassic - Science topic

it's from Upper Triassic - Lower Jurassic I record it with dinoflagellate species

Hello, I am a PhD student in sedimentology and biostratigraphy, and I have a fossil leaf specimen from a Jurassic-Cretaceous deposit. I would like to receive recommendations on fossil plants used in stratigraphy, especially the upper jurrasic and lower cretaceous. Additionally, if possible, could someone help me find specialists or relevant articles on Jurassic and Cretaceous fossil plants?

Thank you very much for your assistance!

Dear Colleagues:

These papers are very old. If you have a copy, please share with me.

Kind regards.

Subhronil

List:

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Kapitza, A. A. New species of lower Cretaceous inoceramid from lower Priamur. 65-77. In: Poyarkova, Z.N. (ed.). Biostratigraphy of the south of the Far East (Phanerozoic). DVNTS AN SSSR, Vladivostok. 139 pp.

M. M. Astafieva. 1989. On the representatives of the genus Maitaia (Bivalvia). Paleontological Journal 23(3):11-19

Keller, S. (1982). Die Oberkreide der Sack-Mulde bei Alfeld (Cenoman-Unter-Coniac). Lithologic, Biostratigraphie und Inceramen. Geol. Jahrb., 64, 3-171.

Heinz, R. (1932). Aus der neue Systematik der Inoceramen. Mitteilungen aus dem Mineralogisch-Geologischen Staatsinstituts in Hamburg, 13, 1-26.

Marwick, J. (1953). Divisions and faunas of the Hokonui System (Triassic and Jurassic). Geological Survey of New Zealand, Palaeontological Bulletin, 21, 1-141.

Chen, J. (1987). Early Jurassic marine bivalves from Guangdong-Nanling district, southern China. Bulletin of Nanjing Institute of Geology and Palaeontology, Academia Sinica, 12, 23-94.

would like to ask you about this thin section which I found in the Upper Jurassic of Algeria."

This question is for an updated paleogeographical reconstruction of the Atlas Gulf and assiociated landmasses in the Early Jurassic (Early Toarcian)

We know that this Paleozoic montane rangue was exposed on the EJ (Frizon de Lamotte et al., 2008), that was being pushed by two rift systems (the Tethyan Atlas rift in the north and the Atlantic rift in the west) and that there was an ongoing exhumation, that cutaround 7.5–10.5 km of crustal rocks by the end of the Middle Jurassic (Gouiza et al., 2017). As well there is evidence it was a source for siliclastic materials in the Early Jurassic Atlas Gulf (Krencker et al. 2020).

But, is there any suggested reconstrucion of it´s appperance? Or a suggestion of what it may have looked like?

-Frizon de Lamotte, D., Zizi, M., Missenard, Y., Hafid, M., Azzouzi, M. E., Maury, R. C., ... & Michard, A. (2008). The atlas system. Continental Evolution: The Geology of Morocco: Structure, Stratigraphy, and Tectonics of the Africa-Atlantic-Mediterranean Triple Junction, 133-202.

-Gouiza, M., Charton, R., Bertotti, G., Andriessen, P., & Storms, J. E. A. (2017). Post-Variscan evolution of the Anti-Atlas belt of Morocco constrained from low-temperature geochronology. International Journal of Earth Sciences, 106, 593-616.

-Krencker, F. N., Fantasia, A., Danisch, J., Martindale, R., Kabiri, L., El Ouali, M., & Bodin, S. (2020). Two-phased collapse of the shallow-water carbonate factory during the late Pliensbachian–Toarcian driven by changing climate and enhanced continental weathering in the Northwestern Gondwana Margin. Earth-Science Reviews, 208, 103254.

This is a Microphotogragh of Jurassic lacustrine shale in Sichuan basin.

These species probably belong to the subfamily Choffatellinae Maync, 1958 or family Spirocyclinidae Munier-Chalmas , 1887 (Image C1,C2) and family Hauraniidae Septfontaine, 1988 (Images C1 & C3).

Image C2 looks like to be Pseudocyclammina Yabe & Hanzawa, 1926

Imge C3 probably is Amijiella Loeblich & Tappan, 1985

Image C1 looks like Alzonella Bernier & Neumann, 1970 or any Cyclamminids but the network of chamberlets formed in the initial whorl is absent in other genera of this family (so far I know).

I´m looking for this work:

Krumbeck, L. (1932). Über den Fallaciosus-Horizont im Lias Mittel-ζ von Irlbach bei Regensburg. Centralblatt für Mineralogie, Geologie und Paläontologie 1932 (Abteilung B. Geologie und Paläontologie), 10, 499-518

Apparently, despite being focused on the Middle Liassic it also recovers the Progadation of Sandstones on the Lower Toarcian Locally (The "Dactyliocerassandstein"). And is one of the few works on this Outcrop of the Lias.

I ask if someone has this paper and can share it as PDF. Or know a place online where i can get it.

Thanks in advance

Antonio

These species have been seen along with possible Calpionellids and possible Saccocoma fragments

I already asked Dr Hisashi Suzuki and Dr Gawlick about the possibility of it being Radiolaria, However they both agreed it is not, though Dr Suzuki did not reject the possibility of it being new Radiolaria specie. It has been seen along with possible Calpionellids and possible Saccocoma fragments and Holothurians of Mesozoic.

I would be thankful to have new suggestions.

Thanks

Hesam

I can't identify these two bioclasts (yellow arrow)in the thin section I'm analyzing. The overall thin section is made up of angular to sub-rounded grains of feldspar with alterations, zonations and twinnings, opaques, lithics and quartz. The thin section was from an area believed to be Jurassic-Cretaceous Tembeling Group based on findings of poorly preserved horsetails in the area. The Tembeling Group is a continental deposit. But the bioclasts seem to be of marine in origin?

The three sections on the bioclast on the left got me thinking that it was a trilobite but I'm not sure. Or could it also be a foram?

We have found in the deep sea sediments in the Jurassic units in the Pontides of Northern Anatolia. The form that may be macrofossil that seen in the pictures. We are suspicious that this form could be a macro fossil (may be of ichthyosaurus). Is anyone have an idea what is this form fossils or another geological features?

It has been seen along with possible Calpionellids and possible Saccocoma fragments.

They have been seen along possible calpionellids

Hi people, i am looking for the following article: Abbink, O. A. (1998). Palynological Investigations in the Jurassic of the North Sea Region:(met Een Samenvatting in Het Nederlands): Proefshift Ter Verkrijging Van de Graad Van Doctor Aan de Universiteit Utrecht (...). Universiteit Utrecht, Faculteit Biologie. I can't get it anywhere. If anyone has a copy I would really appreciate it.

We are working on belemnite jaws and this lead to the question to size limits in belemnite body size. The largest genus is undoubtedly Megateuthis from the Middle Jurassic.

The largest published record of a rostrum is around 500 mm in length to our knowledge.

In our collection, there is a phragmocone fragment where the largest septum has a diameter of over 130 mm.

However, there are certainly larger rostra and I wonder is one of you knows about much larger ones. A fossil collector owns a rostrum that is about 600 mm long, but I could imagine that this is not the limit yet.

I look for photos of larger rostra and phragmocones to get an idea of the upper size limit.

Thanks for your contributions!

The Jurassic shallow water fauna in Eurasia and Tethys is similar to fauna from western coast of North America. The migration is explained by two concepts:

Spanish Corridor – narrow seaway connecting Europe and western coast of North America

Panthalassa steppingstones – terranes located between eastern Asia and western coast of North America

Superficially the reconstruction looks great. However, a moderate issue concerns the fitting of the blocks off Australia. In the published recon (Fig.3a-c), the Lhasa is placed flush against Australia's present-day shoreline - submarine features such as the Exmouth Plateau and the rest of the shelf, which is rather wide) are not accommodated. However, they cannot be ignored. Additionally, the last phase of rifting in the region (Jurassic, ?Middle to Late) had blocks departing from there so there must have been additional material separating the modern day Australian land-sea boundary from the Cimmerian fragments. This flaw is not restricted to the published study and has in fact been repeated in many recent Gondwana models. The topic is important, but this important issue is either being overlooked or ignored. In future publications this definitely needs to be addressed. Regards, Jason Ali (Hong Kong)

Corals and floral traces?

I found this ammonite in the Oxfordian Ammonitico Rosso from the Balearic Islands, Spain.

I would like to know the genus and the species if possible. I'm doubting between Phylloceras and Trimarginites.

Triassic - Jurassic boundary

Following up with the previous questions, I found these specimens in the Oxfordian Ammonitico Rossos facies from the Balearic Islands, Spain. I would like to get some help identifying the genus and species of these 3 specimens.

I suspect that the second specimen, the one with primary and secondary ribs, could be a Taramelliceras.

I need help identifying this ammonite species. It was found in the Oxfordian Ammonitico Rosso facies from the Balearic Islands, Spain.

Hi, nice meeting and talking to you in Quebec. I cannot find your e-mail address anywhere so I try here. Your new generic name for D. habilis? I can't remember it. What is it? and could you also provide me with a reference?

I am finishing a very big MS with a revision of the Jurassic stratigraphy of East Greenland and D. habichi occurs scattered in the paper. It would be useful with a more up-to-date name.

Cheers

Finn

Will the concept of science-fiction genetic experiments to recreate the long-extinct dinosaur species used in the plot of the film "Jurassic Park" ever be possible?

The plot of the film "Jurassic Park" directed by Steven Spielberg is based on a simple, but currently unrealistic concept of laboratory testing of the reproduction of long-extinct dinosaur species.

The collected genetic material of dinosaurs from the blood of a mosquito sunken for millions of years in amber is the main material on the basis of which extinct dinosaur species are recreated.

The genetic material obtained in this way introduced into the germ cell of modern reptiles in the film gives the possibility of reproduction of extinct reptile species.

This idea is based on modern research and genetic experiments carried out in laboratories, whose aim is to create, for example, new crop varieties or produce drugs for specific diseases.

However, the reproduction of long-extinct species such as dinosaurs is still not possible because the genetic material undergoes deep fragmentation over millions of years.

The genetic chain of chromosomes breaks down into very short fragments. So short that there is no information on how to assemble them into whole chromosomes and the lack of enzymes that would be able to fragment these fragmented dinosaur DNA pieces into whole chromosomes.

But the technology of genetic research is developing. The whole genomes of various species of animals, plants and other life forms are studied. The knowledge base of genotypes and related species is successively growing in the Big Data resources created for this purpose.

Therefore, the question arises: Will the fantastic research concept applied in the plot of the film "Jurassic Park" ever be possible? Will it be possible to recreate long-extinct animal and plant species with the help of subsequent generations of research in the field of genetics in the future?

Will it be possible to create a real Jurassic Park in the future, within which dinosaurs will run among the vegetation composed, among others, of flowering and woody ferns, horsetail and ferns, or the restoration of the ecosystem from millions of years ago?

Or maybe a man should not even try this type of other than present ecosystems to play?

Is this also a matter of ethics? Is it not threatening modern ecosystems to restore ecosystems over millions of years, ie consisting of many long-extinct species of plants and animals?

Please, answer, comments. I invite you to the discussion.

Unknown stratigraphic position, found in scree deposits in western Greece. Jurassic up to Eocene carbonate successions is the source for the scree. Conglomerate or breccious limestones are reffered and have been observed only in the middle-late Cretaceous interval, which is not in accordance with early-Jurassic extinct order of the Spiriferida. What else can it be? Expert opinions?

Dear Researchers,

I have collected some Abor volcanic rocks from the Siang Valley, NE India, interestingly the volcanic rocks have shown the Upper Jurassic to Lower Cretaceous age which is different than the previous literature. Is it possible that the Abor Volcanic was emplaced during Indian subcontinent breakup event from Gondwana?

Regards

Upendra

Problem is slove

We are looking for someone to help us determining Callovian-Oxfordian (and possibly Kimmeridgian) benthic foraminifera in order to date carbonate platform successions.

The propose of the electrical resistivity tomography sections is mapping bedrock of a free aquifer in a depth of ~50m. The basin with an area of ~ 65 km² is located in an outcropping area of Guarani Aquifer System, formed by eolian-sandstones from the Jurassic Period (Botucatu Formation) and fluvio-eolians from the Triassic Period (Piramboia Formation). Therefore, it is covered by Cenozoic sediments, with variable thickness in tens of meters.

It come from dolomitic limestone from South-East of France dated from Kimmeridgian (Late Jurassic) following the geological map. This specimen looks like to an Oppeliidae such as Streblites??

What is your opinion? And I know, it 's very poorly preserved, but it is the best specimen!

I need to paleogeographical maps of Middle Jurassic from world and Asia.

this sample represents a Jurassic carbonate sediment (from NE Algeria). It is followed by dolomitized limestone . Thank's in advance.

I look for this article, but is so old for be uploaded: E. Bölau. 1954. The first finds of dinosaurian skeletal remains in the Rhaetic-Liassic of N.W. Scania. Geologiska Föreningens i Stockholm Förhandlingar 76(3):501-502

The questions are: the collected are exposed? any affiliation? any new study?

These diffractograms represents a Jurassic dolomite sediment (from NE Algeria). . Thank's in advance.

This object was found in a ploughed field near Yeovilton in Somerset, England. The underlying rocks are fossiliferous limestones and mudstones of the Lias Group, Lower Jurassic. Fossils found in the ploughed field include ammonites and bivalves, which are typical of shallow marine seas. However, this object does not look like a fossil (e.g. interior cast of an ammonite) in my view, but rather like a piece of sandy clay that has been shaped and smoothed by hand while wet and then baked in the sun. As I did not collect the object and have not visited the locality, I cannot say what other geological or archaeological context or clues might have been present. I just wondered if anyone recognizes this "cashew-nut" look-alike as either a spurious geological curiosity, or as a possible human-made implement (scraper?) or decorative archaeological object?

Dave

The enigmatic structure is indicated by the yellow arrows (look at the photo). The scale bar is in centimetres. I'm not sure what it could be. It was found in carbonate sediments of Upper Jurassic from the Carpathian Foreland of Southern Poland. Thanks!

Any one who had worked on Early Jurassic Palynology/ Need to Identify some polymorphs species.

I am trying to use palynomorphs instead of biomarkers for correlation. Any one having expertise and suggestions.

I've attached a pdf with 4 ostracod photos.  The sample comes from an "ostracod ironstone", thought to be Early Paleozoic, Mackenzie Mountains, western Northwest Territories Canada. The nesting is the curiosity. Thanks.

Because i think that i have sand dikes injected in a sandstone, but i can observe or identificate the unit source for where came from

what are their responses to the environmental changes

In the year 1990 I could find an interesting fossil object (see fotos attached) in the Solnhofen Formation ("Solnhofener Plattenkalke", Malm Zeta 2b) at the locality "Blumenberg" near Eichstätt (Bavaria, South Germany). I don't know to what animal, perhaps to a cephalopod (? nautiloid or ammonoid jaw fragment), this fossil remain belongs to!

The scale/dimension of the fossil object is the following: 4,5 x 2,7 centimeter (max. length x max. wide); the convex surface shows little "points" and "fold structures".

Do you have an idea, to what animal this Upper Jurassic fossil belongs to? Please give me informations and/or fotos for comparisons!

Thanks very much;

Volker

We find some fossil plant remains in Late Jurassic rocks.

Can anyone identify this remains?

This specimen found in the Badamu formation.

Can anyone help me to determine ammonites which I found in Bathonian to Callovian age?

When I read some articles, I found the time was not consistent to the geological time scale. For example, In the Article Archaefructaceae, a new basal angiosperm family　( Sun G, 2002), the fossil was inferred 124.6 mya, and arttributed to upper Jurassic of China. I checked the geological time scale, the Jurassic was between 201.3 mya and 152.1 mya and Cretaceous began 145 mya. How to explain this？

From this formation Come the Fossils of Cryolophosaurus and Glacialisaurus

 The enclosed photographs are from Upper Jurassic - Lower Cretaceous fluvial succession of Gondwana. I am of the opinion of their origin through biogenic activities, however, not very sure. The preservation of the structures is in light to dark gray clayey horizons having abundant leaf impressions of Pteridophytic to Gymnospermus remains. The clay units occur as interbedded horizons with siltstone or, lenicular/poketed occurrence in medium grained sandstone

If it´s possible omit the related to Cryolophosaurus and Glacialisaurus

Jurassic deposits of the Siberia and NE Russia are characterized by numerous glendonite occurences, especially widely distributed in Upper Pliensbachian and Bajocian-Bathonian. Did anybody know any information about the coeval glendonite occurrences in Northern America? I know only two briefly mentioned records of "stellate nodules" in the Kimmeridgian of Northern Yukon and Mid Volgian of Prince Patrick Island 

Can anyone send or recommend me a good paper about Upper Jurassic Carbonate Geologic settings in Western Desert, Egypt??

This fossil Himenofitales fern was collected several years ago by R. Rojas and myself from a Jurassic pre mid-Oxfordian exposure of the San Cayetano Formation in western Cuba. Any suggestion as to species or genera or distribution in time and space?

Dear colleagues!

Can anybody help me with one biological/paleobiological question? Recent Nautilida, as well as many ancient nautiloids, have a cicatrix on their embryonic shell. During formation of the embryonic shell the area of cicatrix initially forms from organic material and later became calcified. Very likely, the shell with cicatrix was the basal type of cephalopod embryonic shell, the second type with protoconch could have appeared later. Monoplacophora is considered as cephalopod ancestor, but I have never seen cicatrix in their shells. Do you know any examples of cicatrix in non-cephalopod mollusks, especially in fossil or modern Monoplacophora?

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The photos of nautiloid cicatrix are from my own collection and from the article R.Chirat, S. Von Boletzky (2003) Morphogenetic significance of the conchal furrow in nautiloids: evidence from early embryonic shell development of Jurassic Nautilida

This specimen found in the Badamu Formation.

This specimn found in the Badamu Formation.

Working at the southern Central Andes we have found some interesting features. In the hinge zone of a broad (ca. 6 km) basement-cored anticline there are sub-vertical clastic dikes of breccia cutting the sequence. The basement is composed by Paleozoic metamorphic rocks and granites and is cropping out several km away from the dikes outcrop. It is covered by Jurassic volcanics of the syn-rift stage of the Neuquén basin. The dikes have between 1 and 3 meters wide and are not oriented in none particular strike. The breccia is composed by basement and syn-rift volcanics angular clasts and boulders ranging from 1 cm up to 50 cm. We are working with the structural data obtained from field work and are interested in any reference we can use to better understand their genesis. The timing of the intrusion is not clearly related with folding, it could be more related with a prior extensional stage in the region...

Who worked on Early Toarcian OAE  based on  ammonites and nanofossils ?

Is there an article on this topic?

We analyzed 8 samples of alterated jurassic basalts. Analysis results of major oxides are attached to this question as a word document. 

What is the reason of high K2O and low total Fe2O3?

Thanks.

It has been shown that different populations of the same plant species can produce longer or shorter n-alkanes for their wax in response to water stress and/or temperature. I would like to know if one specimen at one site can modulate the chain-length of its n-alkane in response to seasonal environmental variation. It is for Paleoclimatic application (Lower Jurassic).

Regards

Tethys evolution

I am looking for the identification and naming strategy for the pollen and spores pertaining to the Jurassic system. Can anyone help me and guide me for any literature and/or catalog available in this regard. Thank you all