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Posts treating: "roadcut"

Tuesday, 10 May 2016

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Glyptorthis costella brachiopod from the Viola formation from Oklahoma 

Views of the Mahantango [2016-05-10 09:01:00]  recommend  recommend this post  (177 visits) info

 Ordovician; US
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The last, identifiable, fossil that I found during my brief visit to the roadcut in Oklahoma that exposed the Viola formation, is the brachiopod Glyptorthis costella. It has a subrectangular shape with valves that are equally convex and decorated with many fine, closely spaced striae. The margin of the valves is flat with no obvious fold/sulcus structure. The posterior of the shell has a nearly flat, wide interarea. Both valves are recurved in the umbo with the brachial valve moreso than the [...]

Wooster’s Fossils of the Week: An encrusted and bored coral (maybe) from the Upper Ordovician of southeastern Indiana (Part II) 

Wooster Geologists [2016-04-01 06:01:21]  recommend  recommend this post  (100 visits) info

 Ordovician; US
Last week we looked at a dull gray rock found in a roadcut in southeastern Indiana near the town of Liberty. It is from the Saluda Formation (Upper Ordovician), a thin unit that was likely deposited in very shallow, lagoonal waters along the Cincinnati Arch. We know that it is primarily a platter formed by

Paleschara or Leioclesma bryozoans from the Kalkberg formation of New York 

Views of the Mahantango [2015-08-24 09:01:00]  recommend  recommend this post  (213 visits) info

 Devonian; DE,US
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These little bryozoan "chips"were interesting to find and I'm trying to figure out what genera they are. They bear a resemblance to Paleschara sp. but they are not encrusting a shell, which is how I find them most often. they could also be another genera called Leioclesma sp. which looks similar but does not have the encrusting habit. Both of the below specimens did start out colonizing a small hard surface with the first specimen growing over an ossicle from a crinoid stem.Specimen #1 - Dorsal [...]

Platyceras sp. gastropod from the Kalkberg formation of New York 

Views of the Mahantango [2015-08-22 09:01:00]  recommend  recommend this post  (196 visits) info

 Devonian; DE,US
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I've found a few gastropod fossils in the Kalkberg formation that are well preserved, which seems to be typical for most NY Devonian material. The below three specimens all appear to be Platyceras sp. with the first two looking very similar to each other.Specimen #1Specimen #2 - a part of the shell is broken and missing and that truncates the outer spiral.Specimen #3 - This specimen is larger than the other two and may just be an older representative of the same species. The coil is covered [...]

Nucleospira ventricosa braciopod from the Kalkberg formation of New York 

Views of the Mahantango [2015-08-16 09:01:00]  recommend  recommend this post  (745 visits) info

 Devonian; DE,US
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I have found only one specimen of the fossil brachiopod Nucleospira ventricosa from the Kalkberg formation but it is somewhat easy to recognize. The shell is oval  in shape with a convex pedicle valve and a slightly convex brachial valve. the shell surface appears to be smooth but actually has a number of small bumps where spines would have been attached. No other ornamentation is visible on the shell nor is there any fold/sulcus structure.Brachial valveAnteriorPedicle [...]

Odd unknown bryozoan from the Kalkberg formation of New York 

Views of the Mahantango [2015-08-14 09:01:00]  recommend  recommend this post  (213 visits) info

 Devonian; DE,US
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I found a number of small pieces of a very small celled Bryozoan that are preserved with a darker colored Calcite than some other fossils found in the Kalkberg formation. They look a little tumbled which makes me wonder if they were washed in from a different area.The fact that only small pieces are found lends some evidence to this hypothesis but it may be that I have just not found an intact specimen, only fragments that weathered out of the rock.Specimen #1Specimen #2Specimen #3These [...]

Streptelasma (Enterolasma) strictum coral from the Kalkberg formation of New York 

Views of the Mahantango [2015-08-12 09:01:00]  recommend  recommend this post  (206 visits) info

 Devonian; DE,US
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The horn coral Streptelasma (Enterolasma) strictum is very commonly found in the Kalkberg formation of New York. It's rugose, or horn, coral that is generally found as small, straight cone shaped fossils often with linear striations along the sides. Most are either crushed or have the calice (the cup like area where the animal lived) infilled with matrix and so the septa are not readily visible. Here are three specimens that I collected from the same road cut that show a variety of sizes. The [...]

Favosites heldebergiae coral from the Kalkberg formartion of New York 

Views of the Mahantango [2015-08-10 09:01:00]  recommend  recommend this post  (245 visits) info

 Devonian; DE,US,IN
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Corals are not terribly common in the section of the Kalkberg formation that I have collected and most of what I have found are small examples. Such is the case with Favosites heldergeriae as seen in these two examples that are about the size of a US quarter.This first specimen has a small mound starting in the center and is spreading out. A side viewWhen it is flipped over you can see the epitheca which is slightly wrinkled. The most notable feature of the ventral side of this fossil is the [...]

Leptaena rhomboidalis brachiopod from the Kalkberg formation of New York 

Views of the Mahantango [2015-08-08 09:01:00]  recommend  recommend this post  (261 visits) info

 Devonian; DE,US
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When you compare the previous brachiopod I posted about, Rhytistrophia beckii, to today's fossil, Leptaena rhomboidalis there are some key differences. Both are large shells that are semiellipical (half moon shaped) to subquadrate (nearly square) with straight hinge lines. The valves of both shells are nearly flat but the margin of the shell in L. rhomboidalis is turned 90 degrees from the regular shell surface all along the edge. Another distinguishing feature is the somewhat regular, [...]

Vermipora serpuloides coral from the Kalkberg formation of New York 

Views of the Mahantango [2015-08-04 09:01:00]  recommend  recommend this post  (224 visits) info

 Devonian; DE,US
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Here we have a strange looking coral that was found in the Kalkberg formation. It resembles cross between a stick coral and an auloporid type coral. The closest match I can find for this is Vermipora serpuloides which I found in the "Palaeontology of New York", Vol. 6, pg. 5, plate ii, fig 24-31:Corallum ramose, consisting of continuous serpula-like cell tubes, withoutintercellular tissue, arising from the center of the branch, and increasing bylateral gemmation. No transverse diaphragms or [...]

Edriocrinus policiformis crinoid "cup" from the Kalkberg formation of New York 

Views of the Mahantango [2015-07-31 09:01:00]  recommend  recommend this post  (174 visits) info

 Devonian; DE,US
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These little Edriocrinus policiformis crinoid cups are somewhat common in the Kalkberg formation of New York. They are a pretty good indicator that the rocks are lower Devonian in age. These fossils are just the base of the crinoid calyx (which may have been free floating) and there were other plates attached that would extend the calyx up to the arms. They are fairly easy to ID as they look like small gumdrops that are hollow.Specimen #1  - The first three photos in this sequence is [...]

Trilobites from the Kalkberg formation of New York 

Views of the Mahantango [2015-07-29 09:01:00]  recommend  recommend this post  (203 visits) info

 Devonian; DE,RU,US
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I have not found too many trilobite fossils in my limited searching of the Kalkberg formation but I did find pieces of two different species.The first are these free cheeks from Acidaspis tuberculatus. Note the knobby extensions that are spaced along the edge of the genal spine up to where the cheek attached to the rest of the cephalon.The other, major piece of trilobite that I found was this thorax-pygidium combo from what I believe was a Paciphacops logani.  I was very excited when I [...]

Machaeraria formosa brachiopod from the Kalkberg formation of New York 

Views of the Mahantango [2015-07-25 09:01:00]  recommend  recommend this post  (240 visits) info

 Devonian; AR,DE,US
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This specimen, that I collected from the Kalkberg formation of New York, has given me some trouble trying to identify it but I think I've narrowed it down to Machaeraria formosa. I'm basing this due to the description by Hall in "Paleontology of New York", Vol III part 1, page 236:SHELL subtriangular or transversely oval; lateral margins forming an angle at the beak of about 90° to 110°. Ventral valve somewhat more depressed than the opposite: beak prominent, arched, not strongly incurved. [...]

Mesodouvillina varistriata brachiopod from the Kalkberg formation of New York 

Views of the Mahantango [2015-07-23 09:01:00]  recommend  recommend this post  (218 visits) info

 Devonian; DE,US
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I recognized today's fossil very quickly due to it's similarity to specimens I have collected from the Givetian stage of the Devonian. This is Mesodouvillina varistriata from the Kalkberg formation of New York. It is a Strophomenid type brachiopod which means that the pedicle valve is convex while the brachial valve is concave. The most identifying feature is the decoration of the shell surface with fine striae which have even finer intermediate striae between them. Otherwise the shell is [...]

Discina sp. inarticulate brachiopod from the Kalkberg formation of New York 

Views of the Mahantango [2015-07-21 09:01:00]  recommend  recommend this post  (632 visits) info

 Devonian; DE,US
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The specimen below is the only one of any kind of inarticulate brachiopod that I found in the Kalkberg formation of New York. It is fused to the shell of an articulate brachiopod (an orthid of some type perhaps) and is somewhat weathered. From what I can see it is round to oval shaped along the margins with the dorsal valve broadly conical and having a central apex. The specimen has been weathered enough to remove most of the surface ornamentation which would help to identify it down to species [...]

Howella cycloptera brachiopod from the Kalkberg formation of New York. 

Views of the Mahantango [2015-07-19 09:01:00]  recommend  recommend this post  (197 visits) info

 Devonian; DE,US
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I found several specimens of Howella cycloptera from the Kalkberg formation of New York for my collection. The shell has a flat hinge line with a semicircular shape along the margin. Both valves are inflated with the pedicle valve equal to or deeper than the brachial valve. A simple ridge and sulcus is present on the brachial and pedicle valve respectively. There are about seven round plications on either side of the ridge/sulcus on the surface of both valves with some some fine concentric [...]

Hindia sphaeroidalis sponge from the Kalkberg formation of New York 

Views of the Mahantango [2015-07-15 09:01:00]  recommend  recommend this post  (180 visits) info

 Devonian; DE,US
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Sponges are not something I typically look for while collecting but some of the specimens of Hindia sphaeroidalis that I found in the Kalkberg formation of New York were nearly the size of a ping pong ball! I know that Hindia is a somewhat common sponge from the Ordovician up through the Devonian but these are the first specimens I have found. H. sphaeroidalis forms a round sphere or ball shape with no one particular surface being an obvious "top" or "bottom". I suspect this is because it [...]

Costellirostra singularis brachiopod from the Kalkberg formation from New York 

Views of the Mahantango [2015-07-11 09:01:00]  recommend  recommend this post  (236 visits) info

 Devonian; DE,US
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I don't have any specimens that are free of the matrix of this next fossil , but they do occur in profusion in some layers of the Kalkberg Formation. It's a brachiopod called Costellirostra singularis and is fairly distinctive. The shell is ovate in shape and wider than long. The pedicle valve is convex around the beak and concave towards the margins with a prominent fold or sulcus. The brachial valve is convex and, when viewed from above or embedded in the rock, appears like it has three lobes [...]

Camarotoechia altiplicata brachiopod from the Kalkberg formation of New York 

Views of the Mahantango [2015-07-07 09:01:00]  recommend  recommend this post  (216 visits) info

 Cretaceous,Jurassic,Devonian; US,IN
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These are a couple of brachiopods that I recently collected from the Kalkberg/New Scotland formation in New York. I believe they are Rhynchonella altiplicata (Hall) based on the description by Stuart Weller on pg. 282 in "Report on Paleontology, Volume III, The Paleozoic Faunas", Geo. Survey of NJ, 1903: Shell broader than long, subtriangular or broadly subovate in outline. Pedicle valve with a pointed, incurved beak, depressed anteriorly in a deep, angular sinus, which extends to the umbo and [...]

Macropleura macropleura brachiopod from the Kalkberg formation of New York 

Views of the Mahantango [2015-07-05 09:01:00]  recommend  recommend this post  (688 visits) info

 Devonian; DE,US
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If I may paraphrase the song "New York, New York" by Gerard Kenny, Macropleura is a brachiopod so nice, they named it twice! Macropleura macropleura is a large brachiopod and hard to mistake for something else in the Kalkberg formation. I've found similar specimens from the Licking Creek formation of  Virginia but there they were silicified. Despite its large size, I've yet to find any whole, articulated specimens. The specimens below both appear to be pedicle valves. They have thick, [...]
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