The first is too bright to decide.. maybe ostracods. The second on the left shows most probalby an echinoderm and on the left a dasycladacean algae.
Dear Mobin,
I agree with the previous comment - the first picture is hard to determine, in the second - the left fossil has a structure resembling echinoderms, the right fossil looks like a section of dasyclad algae.
I agree with Christian and Justyna. In the second picture, the left fossil is a fragment of a pelmatozoan echinoderm (crinoid or blastozoan). The right fossil is a dasycladacean algae. It seems to be Diplopora or something close to it (see papers by Poncet).
It seems that both the sections in the second figure belong ot dasycladacean algae, the left one is recrystallised. In the first picture some spicules (?) surround a number of calcisphaeres (?).
Hi Mobin,
First I have to say that, when you want to photograph from thin section slide, please put scale, so one can get an idea about the size of the specimen.
To me the first photograph shows remains of a foraminfera species which the main body is disintegrated.
The second photograph, may be the cross section of species like coral which the main body in one them is replaced by calcite.
It is better to look for assemblage fossils too.
With best wishes,
Habib Alimohammadian..
First picture, objects in the center, poor resolution, difficult to comments. A long narrow object on the right side - maybe a sponge spicule, look in thin sections on similar objects. Second picture - I agree with previous comments . crinoid and dasycladacean.
the first picture,s probably is microbal trace and second,s probably is coral fossil remained.
Hi Mobin Ebrahim,
The first picture is too hard to decide; for the second picture, i agree with the response of crinoid and dasycladacean.
Best regards,
Hakima
Hi Hakima,
The first picture, probably is an annelids.
Best wishes.
Hi Najeh,
I think you have true, the first picture should be an annelids.
Cordially,
Hakima
Unfortunately there is no scale bar, however in the second image the forms look like "microproblematics". Microfossils incertae sedis present in microfacies.
See Vogler 1941, e.g., Colomisphaera radiata (Vogler, 1941). There is also a stratigraphic chart for them.
Nice images can be found in MICHALÍK, J, et al., 2016. Geologica Carpathica, Stratigraphy, plankton communities and magnetic proxies.......doi: 10.1515/geoca-2016-002, vol. 67, no. 4, 303-328.
Although dealing with Jurassic/Cretaceous boundary, this article gives a nice example of these microfossiles. Geologica Carpathica is on-line and can be easily found. (http://www.geologicacarpathica.com/GeolCarp_Vol67_No4_303_328.html)
the second pic is probably coral. I thought crinoid at first but the test is segmented.I m sorry I cannot help you with the first pic
Top picture: the large fossil looks like a cross-section of a gastropod shell, i.e., one can visualize the spiral nature of the shell and what a cross-section of it would look like. The ground mass of lime mud has a number of sponge spicules (the smaller white finger-nail shapes) and some are perhaps some shell fragments (small bivalves maybe).
Bottom picture: 2 large crinoids. The "segmenting": mentioned above is likely just the different calcite crystals that made up the crinoid stalk. I'm not sure what the more amorphous brown shapes around in the rest of the picture. Algae?
It would be nice to hear from a carbonate petrographer (I'm just a sed/strat guy)..
A scale bar would help.
Many answers were given, some of them with good basis for identification, some other not.
I extend my previous statements. The first picture seems to be a gastropod in origin, but it can not be considered as an internal mold. The shell is missing and only the inner part is to be seen in the picture, but a mold is composed of inflling sedimnentand we have there only cement. It implies a complex taphonomic story. the shell was empty and cemented with sparite. Later, the shell was disolved and moved to a different environment, where other sediment occupied the space of the original Shell. Note that the sediment cover all spaces around the infilling sparite.
The second picture shows left without doubt a pelmatozoan plate (probably crinoid, but blastozoan is not discarded). It has all typical features of that group. As I steted previously, the right bioclast is a dasycladacean, probably Diplopora. Note that it shows radial structures with intermediate pores cemented with sparite. As some answers indicate that it could be a coral, absolutely not. Neither the structure of radial elements nor the microstructure fit with corals.
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