Wednesday, 30 April 2014

Fossils or what? (2)

Posting my question about the mystery traces from a beach in Pula, on The Fossil forum has been fruitful.
The homescar of a limpet would be a perfect answer for the circles, if the place wasn't so far from the tidal zone. They don't come so high and far away from the water. Only very high waves can reach this place. However, I could imagine a loose limpet being tossed away by some very powerful wave ending on this place. Or maybe somebody has brought a limpet there.
A man made origin, like some sort of stand or support with metal feet is another interesting and plausible answer to the riddle. It could have been from some military installation, because the whole Pula area has been fortified as the main naval harbour (at first built and founded as  österreichische Kriegsmarine oder k. k. Kriegsmarine) for over a century. Many forts are still present.
The spot in the photo marked with yellow question mark looks like a man made artifact.

The photograph below is taken at the same place, a few feet further. Red outline is a possible dinosaur footprint.

 The naval base in Pula in 19th century.

Tuesday, 29 April 2014

Fossils or what?(1)

This is a photograph was taken on the beach near Pula a few years ago. The rocks are of the early Cretaceous age (late Albian), I really can't figure out what has happened here around 100 million years ago. You can see some strange long groove-like traces (?) and five circles in a row in the centre of the photograph. Tip of my shoe is at the bottom of the photo for scale.
There are also some rudist fragments, some large ripple marks and possibly theropod footprints near by (not shown in this photograph).

Sunday, 27 April 2014

Albian sauropods and maybe even stegosaurs (2)

There are more seemingly three-toed, oval pes prints scattered around one of the dinoturbations near Pula. They can be noticed among the obvious sauropod tracks. An example is in the bottom photograph with my red outline speculative interpretation. Could it be the  stegosaur Deltapodus ichnogenus? I can't tell for sure. It could be a sauropod or an ankylosaur of the different morphotype from the ones I have found earlier or just the result of the different dynamics in the print making. This natural cast is just about 15 meters away from the one from my previous post (in the upper photograph). It's of the roughly the same size as well.
Here is my "fantasy" scene from Pula mudflats soon after a tempest (which has left a brecciated surface), some 100 million years ago. A lone, late surviving stegosaur is walking carefully along the slippery muddy shore. It looks like Wuerhosaurus. A pterosaur flies by. Soon, a herd of large sauropods will occupy the terrain, obliterating most of the previous tracks.

Saturday, 26 April 2014

Albian sauropods and maybe even stegosaurs (1)

The late Albian sediments in Pula have many sauropod footprints preserved. Below are a couple of examples from different parts of the beach. These tracks are a few kilometers apart and yet they are roughly the same size and of similar shape. What is bugging me, however, is a possibility that these might be a thyreophoran instead of sauropod. While I have found quite a few thyreophoran-ankylosaur tracks in Pula (see my previous posts), these may have belonged to a stegosaur (Deltapodus ichnospecies). This is a pure speculation, because only a few questionable remains of stegosaurs originate from the mid-Cretaceous. By that time, it seems that stegosaurs mostly went extinct as a group. One of the last surviving genera was the Chinese Wuerhosaurus. It doesn't mean that there is no chance some later surviving one might be discovered in the years to come. The print in the bottom photograph is 62 cm long.

Here are some examples of the ichnospecies Deltapodus brodricki, some having manus print preserved and some not (from Whyte and Romano 2001).

In the photograph below is the stegosaur pes track (natural cast) from the Upper Jurassic (Kimmeridgian) from Colunga (Asturias, North Spain), that is housed in the Jurassic Museum of Asturias (Museo del Jurásico de Asturias (MUJA)). Print has three short, blunt and digits forward orientated. It was  assigned this and other similar footprints to Deltapodus.
Size: 55 cm in length and 43 cm in width. It represents the largest stegosaur print discovered so far.

There were also huge sauropod tracks found in Asturias. Some measuring 110 cm in lenght. Some of the sauropod prints from Pula are even larger. I have measured the pes print that was 138 cm long (see my previous posts).

Wednesday, 23 April 2014

Tracks, tracks...everywhere (3)

I don't know if I have been clear enough, so far. This cape Kamenjak track site is NEW and has not been described yet. Nobody has noticed nor detected these Cenomanian dinosaur tracks. I call it "Kamenjak 3".
I've been analysing my photographs from this site and the site that was described to a certain degree in Fabio's (Fabio Marco Dalla Vecchia) paper (Grakalovac promontory), which I have named "Kamenjak1" and all my finds lead to this conclusion: In Cenomanian (late Cretaceous), Istria was a part of a large piece of land (Adriatic Dinaridic Carbonate Platform - ADCP) sustaining viable populations of various types of big dinosaurs. It was either a very large island or still Afro-Arabic  peninsula. Not only that I speculate that a large tyreophoran track is present on Grakalovac (see my previous posts), but it seems quite big ankylosaur was present on this new site, too. While this is still just a possibility because the tracks are poorly preserved (one is outlined, while the other is under my foot), the  theropod footprint beside them speaks for itself. The largest one was some 73 cm long. The print is shallow, because the substrate was already quite dry when it was made, so it effected the mud cracks. The "owner" of the foot must have measured at least 9-10 meters in length! I have outlined the probable prints.

Here is the size and shape comparison of the theropod tracks from "Kamenjak 3" site (red bar is 12cm long). The largest footprint is from the photograph above.

Tuesday, 22 April 2014

Tracks, tracks...everywhere (2)

I've been to Pula over the Easter holidays, but didn't have time to visit the Kamenjak sites. However,
I tried to analyse the old photographs once again. Here is the result (below). I am positive now that the mid footprint was no ornithopod but a fairly large theropod with very long middle  toe (#3). A smaller theropod (green outline) was crossing diagonally the path of the large one (or vice versa).

In Pula, the first tourists are sunbathing and even swimming in still rather cool sea.

Friday, 18 April 2014

Tracks, tracks...everywhere

The tridactyl dinosaur footprints are omnipresent in the Cretaceous laminated sediments of Kamenjak. The problem is: they are not that easy to spot. Nor they are easy to define, because they are in a different state of preservation left on a varying substrate. Imagine a mud flat. The tide has just receded. The first dinosaurs to cross the mud will leave deep, often collapsing tracks. As the mud dries, the next tracks will be less and less visible. Dinosaurs step over the tracks left by the other dinosaurs (or themselves) earlier, making them deformed. The waves start to wash the shore. Some of the dried tracks will be erased, some will remain and get covered with the sand and mud. The trackways are often messy.
Here is an example of a dinoturbation with various types of tracks. I tried to interpret some of the tracks with the red outline. It seems that at least three kinds of theropods left their footprints. Of course, I couldn't see all the prints. It's hard to notice them and take photographs with a digital camera on a bright sunny day with almost white rocks reflecting light from all sides.

A close-up with somewhat different interpretation of the tracks in the middle of the outcrop (below).
The footprint is about 45 to 48 cm long. If my interpretation is correct, that transfers into a 6-7 meters long predatory dinosaur. You wouldn't want to meet such a beast! The other theropod was obviously much smaller.

A photograph of the Kamenjak's carbonate rocks below. These rocks are hiding hundreds if not thousands of Cretaceous tetrapod tracks for those with enough time, patience, determination and most important a good eye to discover and describe them.

A look back at the Porer islet with the lighthouse which is behind us now. We are walking towards the tip of the cape.

Tuesday, 15 April 2014

Back to Kamenjak

If you don't mind the heat, the south Istrian cape (rt) Kamenjak is a nice place for trekking and observing the nature in Spring time. You may even get lucky and see the extremely rare monk seal.
It is too hot for me to walk during the Summer, but there are plenty of nice beaches to go to swimming or snorkeling. The islet Fenoliga which has numerous (although weathered) dinosaur tracks is visible in the distance, between the cape on the left and the light house (islet Porer) on the right. One can see the rudist fossils along the way.
While walking towards the tip of the cape I have noticed an interesting rock in a farm's wall (suhozid). It looks to me it might be an impression of a late Cretaceous plant. See below, far left in the photograph. I'd appreciate if any of the blog readers can help me out in identifying the fossil (or is it just an artifact?) Could it be the mid-Cretaceous angiosperm Sapindopsis angusta? In fact, it resembles some kind of psilophyte plant. The environment was supratidal-intertidal  with extensive mudflats, where dinosaurs left their tracks. There were rudist reefs and  stromatolites in the shallow sea of the lagoons.
Maybe it was some kind of an algae washed ashore (?)

A common sight at Kamenjak are sheep herds.

In some places, the path gets quite narrow because of the rich flora.

And here is the view at the Fenoliga islet. So close, but out of reach if you don't have a boat.

Fabio's paper describing the Istrian Cenomanian tracks. Kamenjak and Fenoliga sites are included.

Here are the Istrian Cenomanian theropod prints (outlines) from the paper:

A few of the footprints have a "fat" middle toe (toe # 3) padding. Below is the photo and my footprint interpretation of another theropod track from Kamenjak's outcrop just across the Fenoliga islet. There are at least two more prints of the same dinosaur at the site. None of the images above fit to that morphotype. The foot is about 34-38 cm long. I am not sure about the heel: is it all heel or also a drag mark?

Notice the unusual shape of toe #4. At first I had thought it was a substrate deformation due to the footprint pressure, or some sort of a drag mark, but than I saw the other prints had the same feature. Maybe it's not a theropod at all. Maybe it's an ornithopod track.

After all, the emerald sea looks inviting!

Monday, 14 April 2014

A theropod or not

 Another example of a dubious footprint from late Albian rocks of Pula. I have interpreted it as a tridactyl track. It's probably a theropod. But I am not sure. It may be an ornithopod and even a thyreophoran. There's a short trackway there on that rock that may be thyreophoran and I have attributed one footprint to an iguanodontoid. There's even a chance that all those tracks of relatively small size belonged to the same animal. Making a detailed sketch of the outcrop and taking some casts would probably resolve the dilemmas.

 A small modern "theropod" was watching me taking the photographs.

Friday, 11 April 2014

Dinosaur comic

A few words from author/editor/blogger

 A quarter of the century ago my friend Brian Franczak and I started a dinosaur comic project called "Lost Worlds". We were very enthusiastic about it. I think we have done some 12 finished panels and about the same amount of pencils. To make the long story short, the project never took off and was abandoned. For some time I have been thinking of reviving it. Many years have passed, and an enormous amount of new discoveries were made in the meantime, making it ever harder to use the old drawings without going into extensive, time consuming revisions. Nevertheless, I have decided to try to update the comic panels and publish them one way or another. So here it is. The first episode is published on my blog Dinosaur comic. A lot of work went into the production and revision. I hope you'll enjoy reading. Anyhow, this comic is given a second chance, but its frequency and its life span will depend on your visits. Like everything else on the web.

Berislav Krzic

Wednesday, 9 April 2014

An Istrian theropod tracksite destruction in 2012

In the photograph below is a small theropod trackway consisting of four footprints with seemingly rather long heel impression or drag mark (or both). The dinoturbated site is Lovrečica, Istria, Croatia, of the upper Cenomanian age (late Cretaceous). The best preserved footprint #3 shows some considerable damage (the displacement rims are broken off) left by the bulldozer which was working on nearby road construction. Some other tracks at the site were damaged to the even greater extent  and some track baring rocks are missing. The event raised a lot of dust in the daily newspapers in 2012, claiming that some of the tracks were stolen. In my opinion this is a clear case of irresponsibility and negligence towards the geological and natural heritage, by the local construction work investor and the contractor. The local community is to be blamed for not protecting its main natural history attraction. Unfortunately, the damage is irreversible, like usually in such occasions.
The footprints in the photo are about 23-28 cm long (give or take the "heel"). The animal was probably some 3 to 3,5 meters long. The prints marked with the question marks in the diagram are rather speculative.

Some of the sensationalist headlines  in the Croatian media, regarding the tracksite destruction:
Dinosaur tracks stolen with a bulldozer
Dinosaur tracks stolen in Istria using a bulldozer 

The paper where some of the Lovrecica tracks were described in 1998:

In the comparative drawing above are some of the footprints from the Lovrečica outcrop (the scale bar is 10 cm): the middle one is redrawn from Fabio's paper; the right one is from my photograph in this post.

Tuesday, 8 April 2014

Small sauropod footprints at the beach (2)

Here is one of the sauropod tracks on the limestone beach near the city of Pula. The length of the pes in the photograph is almost 80 cm, while the sauropod pes from the same age Solaris outcrop photo (see my previous post) is about 30 cm long. The largest sauropod footprints near Pula are about 120-130 cm long. It is interesting that in this track set the manus is a positive (cast) while the pes is concave.

Monday, 7 April 2014

Small sauropod footprints at the beach

Presented here in the photograph are the three small sauropod footprints, each one facing different direction. So they do not belong to the same trackway. The one in the middle is less preserved. This is from the Solaris late Albian Istrian site where Fabio Marco Dalla Vecchia described and named the ichnospecies: Titanosaurimanus nana*.
The best defined print in the photograph (on the right) is very similar in shape to the sauropod prints I have found near the city of Pula. Fabio concluded the fauna of Solaris compound consisted of dwarf dinosaurs. However, the tracks I have discovered near Pula (Pola) were significantly larger.

New Dinosaur track sites in the Albian (Early Cretaceous) of the Istrian Peninsula (Croatia).
FORWARD. This contribution is the first of a series of papers which we wish to dedicate to the results of the detailed study of the Cretaceous paleoichnological sites cropping out in the Periadriatic Carbonate platforms and follows several prelimiary ic

Anno    2000
Titolo    New Dinosaur track sites in the Albian (Early Cretaceous) of the Istrian Peninsula (Croatia).
Rivista    MEM.SCI.GEOL.
Serie Volume    52/2:193-292
Illustrazioni    FIGG.75, TABB.10, 1 PL.

Riassunto / Abstract    FORWARD. This contribution is the first of a series of papers which we wish to dedicate to the results of the detailed study of the Cretaceous paleoichnological sites cropping out in the Periadriatic Carbonate platforms and follows several prelimiary ichnological descriptions (e.g. Dalla Vecchia, 1994; 1996; 1997a,b, 1998b; Dalla Vecchia and Tarlao, 1995). Despite that the presence of dinosaur footprints in the Istrian sector of the Adriatic-Dinaric carbonate platform was known since 1925 (Bachofen-Echt, 1925a,b), until very recent years nobody fully understood the great significance of this presence under the paleobiological, paleoecological and paleogeographical point of view. Dinosaur footprints reveal also the potential that these fossil traces may have for aiding sedimentological and modern stratigraphic analysis, such as the cyclostratigraphy. Multidisciplinary study of the sediments and traces yeld fundamental information about the palaeoenvironmental conditions of the different sites. In many cases recognition of subaerial episodes may be possible only because dinosaur prints were found. The number of sites with dinosaur evidence in the Cretaceous Periadriatic Carbonate platforms increased dramatically during the last years, particularly in the northern sector of the Adriatic-Dinaric carbonate platform (Fig. 1). The names of the sites are given in Croatian and Italian (the latter in Italics) in order to indicate both the actual names and those to be found in italian literature and topography of the region. Footprints have been found in the upper Hauterivian, upper Barremian, upper Albian and upper Cenomanian of Istrian peninsula, where also late Hauterivian-early Barremian bones were discovered (Boscarolli et al., 1993; Dalla Vecchia, 1998a). The Istrian levels containing bones are located in a large depression filled with marginal and open lacustrine carbonates (Dini et al., 1998). Dinosaur footprints are present also in the upper Hauterivian of the Cansiglio Plateau of NE Italy (Dalla Vecchia and Venturini, 1995; Dalla Vecchia, 1999) and in the Senonian of Murge, S Italy. Important discoveries of complete dinosaur skeletons and scattered bones and teeth have been done in the lower Albian of Pietraroja (S Italy) (Dal Sasso and Signore, 1998), and in the upper Santonian and Campanian/Maastrichtian of Karst, NE Italy and Slovenia. This paper concerns track sites of late Albian age found in two localities of western coast of Istria, respectively Solaris camp site, near Cervera/Cervar, Tar municipality (NW Istria) and Puntisella /Puntizela, near Fasana/Fazana (SW Istria). The paleoichnological field work in the Solaris camp site was possible thanks to a grant of the late The Dinosaur Society, which permitted to collect a lot of data and, in particular, to execute a detailed map of the site and the casting of several footprints. For this reason, the present contribution is particularly "conspicuous" and had to be divided into two parts. The first concerns the aspects most related to sedimentology and stratigraphy (authored by Giorgio Tunis and Sandro Venturini), the second (by Fabio M. Dalla Vecchia and Alceo Tarlao) is dedicated mainly to paleoichnology and paleobiological-paleogeographical aspects.

Saturday, 5 April 2014

My old Nanotyrannus drawing

I don't know when exactly did I make these drawings of Late Cretaceous tyrannosaurid Nanotyrannus lancensis (Bakker, Currie & Williams, 1988), but it was probably sometime in the late 80's or early 90's of the previous century. I think that I used the photographs of the fossil published in Discovery magazine as reference. According to my knowledge at the time, I drew theropods with lizard-like lips.