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  • JohnJ

    Ancient Hunters

    By JohnJ

    June 5, 2010 Barry held his camera barely two feet away from the back of an Agkistrodon piscivorus. Although a small snake, it was still very dangerous and he positioned his camera based on years of experience with these reptiles. Known more commonly as a Cottonmouth or Water Moccasin, the twelve inch juvenile snake had coloration similar to the closely related Copperhead. However, its patterns were muted by late afternoon shadows in a remote location that was not favorable to an easy medical evacuation. So, we slowly moved away and eased our paddles back in the water to complete an adventure which began long before daylight.     Almost twelve hours earlier my friend and I had packed our gear, food, and water into my eighteen foot canoe. Soon after, our paddles fell into a synchronous rhythm that allowed us to quietly experience an aquatic wilderness. We were searching in Texas - hunting in alluvial debris and Pleistocene terraces for the slightest hint of extinct creatures. Our unrushed pace allowed us the time to get a feel for the local geology. Occasionally, groundwater from the surrounding area made its way to the base of the Pleistocene gravels and created springs which emerged just above older impermeable shale. The cool water supported rich vegetation that resisted the summer sun. It was also a visual key to the strata we were trying to find.     A little later, we found an area where the gravel spilled onto a ledge just above the water. Almost immediately I spotted a gravel encrusted bone fragment. I looked over to see Barry higher up on the river terrace. Still scanning the area, I hollered, “Hey, I found some mineralized bone over here. Uhhh…wait, here’s another one.” I noticed the second piece was gnarly and pitted while Barry made his way down to inspect my finds.   “What do you think of the encrusted bone?” I asked.  He replied, “Not sure; but there’s no doubt it’s old. Which bone do you think it is?”   I tried to imagine the fossil without the encrusting gravel, “Looks like it could be the ‘joint’ end of a scapula…I’m not sure about the second one, though.”   Before and after cleaning – proximal scapula & unknown fragment   I headed back to the canoe to pack away my finds while Barry searched further down the ledge. It wasn’t long before he yelled he had found more bone, and after I paddled the boat over to him, he grinned and asked me to find the camouflaged fossil. The fragment was difficult to spot amid the varied textures of rock and silt. We were off to a good start.   Barry's mineralized bone fragment   In Texas, June temperatures can quickly reach the upper 90’s. We maintained a regular fluid intake and an occasional soak in the water. Proper hydration and cooling were essential for us to enjoy an amazing adventure versus a headache pounding endurance test. Since we still had more than a dozen miles to travel, the hot conditions could not be ignored.     A few miles later a short rocky ledge barely emerged from the water. It looked like a good spot to check and take a break. What I really did not expect was to step a few feet from the boat and see a broken stone dart point. I looked at it with a little skepticism; the area seemed like a place fisherman would use to access the water and I wondered if someone had passed the time trying to replicate an ancient weapon. But the patina on a few nearby flakes confirmed the find was old.   Barry searched the rocky debris fan on the downstream end of the ledge. I let him know to keep an eye out for more than bone and kept scanning the ground. Before me was an area the size of two cars where the water had peeled away part of an upper bank which had slipped into the water. I stopped. There, in the gravel and weeds, were more flakes…and another dart point! As I reached for my camera, I saw another broken point by my knee…a cool moment. Then things started to get comical - in an amazing sort of way - because as I took the photo of the first point, I spotted a third one just beyond it…an incredible moment!     Still kneeling in the same spot, I yelled to Barry, “Hey, you’re not going to believe this, but I’ve found…hang on….” I shook my head in disbelief at the fourth late Archaic projectile point tucked in the gravel. “You have to come over here, now,” I smiled. I tried to explain to him what had just happened – pointing out each of the finds. He was as awestruck as I, but we both almost lost composure when, within seconds of ‘show and tell’, another light colored point met my eye a few inches from where I laid the paddle. I edged backward to get a good camera angle. Then, I just looked up at Barry in stunned silence and back down again beside my other knee at a small gray-purple dart point. That is when we both erupted with the excitement of two kids.     “I’m now walking away. There have to be more here; so you find them,” I jokingly announced as I headed upstream to survey the ledge. Savoring an unbelievable fifteen minutes of discovery included the analytical questions forced by the finds. Often people have asked, “Where did these artifacts come from?” Sometimes the answer is simple because the ‘site’ still exists. Other times, I will touch two fingers together in front of me, representing a point in space, because similar coordinates may be all that remain of ancient eroded camps. My quick recon of the area seemed to confirm a similar origin for these artifacts. Our timing had offered us the chance to experience something that would have been erased by the next flood.   My six dart points fill Barry’s hand   Barry’s voice carried down the bank, “I found one!” I saw him gently scratching the sand and gravel in the weeds. I took in the view of the area because I wanted to remember this place and time. Barry called out again, “Hey, you should see this large white base I found!” By the time I made it back to him, he had found another dart! While he pointed out his finds, I felt like we were functioning in a mild state of shock – still trying to wrap our minds around what was happening. After a few more broken finds and photos, we cooled off in the water. In all we found 19 pieces; some were complete and some were fragments.     Dream-like remnants of the artifact discoveries stayed with us for miles. I told Barry I was not sure I would have believed the event if I had not been part of it. Roughly thirteen hundred years earlier, someone made the weapons we found. Handling them was like touching an old pocket knife owned by your great grandfather or holding an old wooden spoon used by your great grandmother - except, they were much older and no one remembered the owners anymore. We could not know what the circumstances were during the last moments someone held these artifacts, but we were the next men to hold them and imagine those days.   We found a few pieces of fossil bone over the next couple of hours and it really began to get hot. To get relief from the temperature, we paddled closer to the shady banks. On few occasions we startled beavers from their dens. Not many things can get your attention quicker than a forty pound animal hurtling into the water on the edge of your vision. My only regret was that the camera had not recorded our comical reactions.   Then, as we rounded a large bend, a huge gravel bar came into view. In the distance, I could see something big lying on the rocks. “Barry, what’s that?”   “I don’t know….” He shaded his eyes and leaned forward, then exploded, “IT’S A HUGE GAR!” He spun to face me, “Can I have the SKULL?!” He spun back, “It’s HUGE! You’ve got to let me have it, please!”   He sounded like a ten year old begging for his favorite birthday present. It was hilarious. But my smile was temporarily gagged when I caught a whiff of the almost dry carcass. “If you can separate the skull from the rest, you can have it…but it stays on your end of the canoe,” I winced.     The smell matched the size of the alligator gar – it was a monster. I was fascinated to see such a large specimen up close. Barry finally separated his prize from its ragged remains. Then, he placed it in the canoe under his seat and we continued to search the bar.     The multi-colored gravel camouflaged many pieces of petrified wood and the new ‘gar skull owner’ took advantage of the canoe’s carrying capacity. We left shore a little heavier and smellier. Unfortunately for me, the prevailing wind came from the bow of the boat. I joked with him about the odor coming from his direction, but he firmly insisted he was unaware of any stench.   On another bar, the gravel teased us with more bits of bone; then Barry spotted a large brown lump. He called me over to take some photos. Whose bone he had found was not immediately obvious; but it had some size. Only after he freed it from the sand were the features of a large vertebra confirmed. Likely from a mammoth, it had suffered the erosive effects of time and water. Yet, Barry grinned. He had accomplished one of the goals we had for the trip – find mammoth bone.         The heat was relentless, but we kept cooling off and drinking. Even the butterflies were frequently tapping moisture and minerals in the damp sand. Eventually, we reached an area where the channel narrowed and we took advantage of the shade. I was looking for beaver dens when Barry cried, “Snake! Back there by the large stump!”     We buried the paddles in a series of strong back strokes to reverse our direction. I finally spotted the handsome reptile crawling into a small pile of logs. I could tell he wanted to catch it, when he almost whispered, “Elaphe obsoleta lindheimeri.” After three seconds of heat affected thinking, I realized he had not issued curses to move faster, but had just named the scientific classification for a Texas Rat Snake – the name that had passed through my mind 5 seconds earlier….  Barry scrambled up the bank and had the snake in hand within two minutes. He slowly manipulated it while I took photos. I have always enjoyed my encounters with these non-poisonous reptiles. They can be very aggressive and strike repeatedly, or try to intimidate any threats with their loud hiss and vibrating tail. He left on the log where we found it.     About a half hour downstream we were exposed again to the late afternoon sun. It reflected from the water and the barren high bluffs beside us. We paddled and scanned both water and banks. Through the salty sweat in my eyes, I saw something out of place halfway up one of the bluffs.   “OK, that can’t be what I think it is, can it Barry?” A bowling ball sized dome contrasted sharply with the surrounding tan soil. We slowed the canoe to a stop. I remembered the “dome” of a four foot mammoth humerus I had found almost a year earlier…. My heart rate increased.     Barry insisted, “John, that shape is too perfect; it has to be a bone.” The closer we got the boat, the more my pulse quickened. From fifteen feet below it, I still had to get closer to allow myself to acknowledge the obvious…it was a bone!     We positioned the canoe as close as possible to the vertical bank. The water was not moving fast there, but it was deep. In a tricky move that involved me stepping on the tip of the stern and stabbing my rock hammer into the soil of the steep ledge above, I pulled myself up to a spot where I could rest. Our access point was a little downstream of the “dome”, so I had to dig footholds to make my way to the find. It was impressive when I could finally rest beside it. “Hey Barry, it’s bone!” I grinned.   After a difficult time staging a few digging tools, we started to excavate. I carefully determined the perimeter of the fossil and had some vivid flashbacks to last year’s humerus find. However, the deeper we dug, the more it became apparent that the rest of the bone was not attached. We tested the ‘ball’ for movement and it popped free of the matrix below. In the soil below, we did not find any more evidence of bone.     Initially it seemed there was a large scavenging scar across the surface, but after cleaning, the mark appeared to be an eroded part of the internal vascular structure. Other old gouges and marks may have been due to ancient scavenging. Shape and size suggested I had found my first mammoth ‘femur ball’ or the head of the femur. Regardless of the number of mammoth fossils I have found, they never cease to spark my imagination.   Mammoth femur head – approx. 7 inches in diameter     Scars and vascular structures   The shadows had begun to lengthen by the time we loaded the femur ball and started back downstream. Temperatures had dropped a few degrees which energized us for the next few miles. In a large eddy, we saw another snake crossing the water and sped up to see it. Both of us recognized the juvenile Water Moccasin as it paused and floated on the water. Barry pulled out his camera and I positioned the canoe to assist him. All was going well until the young snake thought the boat would make a good rest stop. The most important result of the next few moments was that no one entered the water, and nothing entered the canoe. I repositioned us to allow the little pit viper to reach the bank. It seemed to respond to the security of solid ground and assumed the confident demeanor of the species.     We reached the take-out after twelve hours on the water. Tired, but feeling the satisfaction of an incredible adventure, we completed a relatively short shuttle run back upstream. The trip had so many layers – so many memories. We hunted and found what we sought. And somewhere between our imaginations, the water, willows, cottonwood, and stone, we caught a reflective glimpse of the ancient hunters.
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  • andreas

    The Columbianus Zone/alaunium 2/ Norium/upper Triassic, In The So Called “Hallstatt Limestone” Of The Northern Calcareous Alps In Austria

    By andreas

    The columbianus Zone/Alaunium 2/ Norium/Upper Triassic in the so called "Hallstatt Limestone" of the Northern Calcareous Alps in Austria Dear Fossil Forum members! This pictured report about the ammonite bearing Triassic Hallstatt limestone will be the first one of a continuous series of reports. Since the beginning of the geological research in the Northern Calcareous Alps of Austria in the 19th century, about 500 species of Triassic ammonites have been described from the Hallstatt limestone by Mojsisovics, Hauer, Diener and other authors. The most important person in the development of the first Alpine Triassic ammonoid biostratigraphy was the Austrian palaeontologist Edmund von Mojsisovics. When viewing his classical monographs one is overwhelmed by the stunning Lithographics created by the artists of the late 19th century. Every recent serious triassic ammonoid researcher includes these old works in the standard literature of triassic ammonoids. Unfortunely his ammonoid bio-chronostratigraphic scale had some mistakes (changed zones) especially the incorrect stratigraphic position of some ammonoid zones in the Norian stage. It was the merit of E.T. Tozer to discover this weakness and to correct it. Hallstatt limestone facies is a type of triassic Ammonitico Rosso facies which also occurs in several other locations all over the world. The Hallstatt Limestone Facies of Austria consists typically of red to grey –coloured, in some parts abundantly fossiliferous limestones locally interbedded with marls. Also strongly condensed successions are common. Fossils mostly do not occur in continuous layers but in so called lenses and fissure fillings. The most common fossils are Ammonoids and Nautiloids, but Crinoids ossicles, Bivalves, Conodonts and Gastropods also occur. In this report I will introduce you to the Triassic ammonoid zone of the Alaunium 2 /Norium/ Upper Triassic of the Hallstatt formation. The stratigraphic level lower Alaunium 1 will be shown in a future report. Fig.1 A very beautiful view of a tectonic border. The Valley in front marks the tectonic border between the mainly Triassic Hallstatt unit und the Tirolikum unit of the Totengebirgs nappe. The highest mountain shown on the picture is the "Loser". The well bedded limestone in the summit area are of Jurassic age. This is in turn resting on Triassic "Dachstein" limestone that ends roughly in the middle of the picture. The name of this stage was chosen by Mojsisovics after the Celtic folk of the Alauns. In historical times this tribe lived in the forelands of the calcareous Alps in the area of the later Roman province Noricum. Zone ammonite of the Alaunium 2, outside of the Tethys realm, is Mesohimavatites columbianus Mc LEARN, well known from the boreal Triassic of British Columbia in Canada. In the Tethys realm the whole Alaunium is split into three subdivisions. Alaunium 1 = Bicrenatus -Zone, Alaunium 2 = (instead Columbianus) Hogarti- Zone, Alaunium 3 = (instead Columbianus) Macer -Zone The subzones I-IV shown in the timescale below were established after bed by bed collections in the well-bedded erratic limestone blocks of Timor by the Austrian geologist Franz Tatzreiter. Fig.2 In the Hallstatt limestone of the northern calcareous Alps, Himavatites sp. occurs very scarcely. It is impossible to use this genus for Stratigraphic aims on new detected locations. A normal collector could use the following rough scheme to insert ammonoids in the right stratigraphic subzone. But notice that strong condensation, fissure filling etc. can blur this schema. For a newbie collector it is much more difficult to find some fossils there at all. To place them into the right ammonoid zone is the easier part of the exercise. Rough scheme, to place ammonoids into the right subzones of the Alaunium 2 in the Hallstatt limestone. Subzone I+II: Distichites (especiallys in II) but no Halorites, Subzone III: Halorites starts, Distichites can be found too, but ends in this subzone, Subzone IV: Halorites frequent, main zone of „catenate Halorites" especially in the later time of this subzone. In the upper sphere of subzone 3 and in the lower sphere of subzone 4 Halorites sp. is a very common faunal element. In locations which expose this time interval Halorites is more common than other leiostraca (=ammonoids without sculpture) ammonoids like Arcestes sp. The often used term Halorites horizon (KRYSTYN, L., 1973) points that out exactly. Representative for the family of the Haloritidae, is shown Halorites ramsaueri (QUENST.),.Sommeraukogel, MOJSISOVICS (Bd. II), Wien 1893, Tafel 71, 76 und 77. Fig.3 The venter views laterally right show the variability of the end living chamber (after pictures by MOJSISOVICS Bd. II, Wien 1893) of Halorites ramsaueri QUENST. The right venter view could also be termed as a Halorites macer. The difference between H. macer and H. ramsaueri is not clear due to the great variability of these two species and is totally questionable in my opinion. Fig.4 Catenohalorites catenatus BUCH form MOJSISOVICS (Bd. II), Wien 1893 To the genus „Catenohalorites" count all species of Halorites, which show the chain like („catenat") arranged nodes of the inner whorls on the phragmocon too. (The inner whorls are more or less catenat by all Halorites sp.) Historical locations Beside the well known historical location of the Sommeraukogel, which exposed all four subzones, there are several other historical locations. For example: Hallein, Hoher Student, Leisling, Pötschenhöhe, Rossmoos and Röthelstein. Years ago I was lucky to find a talus block in an area of such an historical location. Later in this report I will show the ammonoids of this block. Two new faunas shown here in this report came from locations hitherto not yet described. Fauna 1 The first new location is in an area where the normal succession of limestone is penetrated by fractures with fissure filling and reworked horizons. One reworked horizon (not for sure yet, it could also be an untypical fissure filling) shows a Halorites fauna. Two nearby located, clear fissure fillings show a faunal association with Distichites but without Halorites. A shell fragment of a Himavatites sp. in the Distichites fissure may confirm the higher hogarti zone. One highlight of the Halorites location was the discovering of a Bambanagites MOJS. 1896. This is the first evidence of this genus in the Hallstatt realm. So far Bambanagites is yet only known from the Halorites limestone of the Bambanag- succession on Niti- Pass (Himalaya) in India, described by MOJSISOVICS with two species (B. schlagintweiti MOJS. and B. dieneri MOJS) In Dieners work, „Fauna of the Tropites-Limestone of Byans", another species, B. kraffti DIENER, is described. The Venter of B. kraffti is very sharp with only weak waves on the flank. Further research on Bambanagites (member of the family Pinacoceratidae) resulted in no other location/occurrence than the above mentioned location in India. Maybe Bambanagites occurs also in the Triassic of Timor. I haven't found any citation but judging by the frequent occurrence of fauna of alaunian ammonites there, it could be possible to find some. Fig 5 Bambanagites cf. dieneri MOJS. a first evidence in the Hallstatt limestone of the eastern Alps, possibly a worldwide first evidence outside the type locality in India. Fig.6 Bambanagites Dieneri, MOJSISOVICS 1896 .Cephalopoden der oberen Trias des Himalaya Taf. XVIII, Fig. 3 - 6. The impression of the Bambanagites sp. is on the backside of this slab with Halorites cf. macer MOJS.(8cm) on the following picture Fig.7 Halorites cf. macer MOJS. found in the location together with Bambanagites Fig.8 Halorites sp. with very prominent nodes on the venter Fig.9 Washed block from this location, with visible Halorites sp. Several other ammonoid species are also visible on this block which are frequent in the Alaunium 2. Rhacophyllites neojurensis QUENST. , Placites sp,, Halorites div. sp., Arcestes sp., Leislingites sp., Megaphyllites sp., Paracladiscites multilobatus BRONN., Steinmannites hoernesi HAUER, Alloclionites ares MOJS It is further worth a mention about the occurrence of the Ammonite genus. cf. Psamateiceras in this location. Natural picture size is 45cm. Other important ammonoid species of the macer zone A beautiful, conspicuous faunal element of the macer zone is Steinmannites sp. With different species this genus shows its maximum in this zone and was found relatively frequently in this location within the Halorites location. Fig.10 Steinmannites hoernesi (HAUER) from the Halorites-area in compairson with a Fig.11 cf. Eosteinmannites sp. from the Distichites-area of this location. Fig.12 ? cf. Pseudosirenites sp.(3cm) or cf. Mesohimavatites sp. from the Halorites-area Fig.13 Paracladiscites multilobatus BRONN. (5cm) Another frequent faunal element of the Alaunium 2 is Paracladiscites multilobatus BRONN. This species differs from Cladiscites and Hypocladiscites by the absence of the spiral striations. Only fine radial growth lines are visible on the shell. The genus Paracladiscites reaches throughout the whole columbianus- Zone up to the zone of Sagenites reticulatus/Cochloceras/Paracochloceras (Sevat2) Distichites Fig.14 Distichites megacanthus MOJS. from the Distichites area of this location. Fig.15 Venter view of Distichites megacanthus MOJS. Diameter is 19 cm; this is rather the growth limit of this species. Distichites sp. is easy to determine by the two bulges following the venter furrow Fig.16 Distichites cf. kmetyi (8cm) of this location Distichites were found in different species at this location but very scarcely. From 30-40 other ammonite's roughly one piece of Distichites sp. was found. Most common ammonites are Placites and Arcestes. Fig.17 Rhacophyllites neojurensis QUENST. (7cm) from the Distichites-area Rhacophyllites sp. runs up to the Sevat Fauna 2 The second new location comes from another area and is also a reworked horizon. This horizon is associated to a small tectonic fault which strikes through the surrounding normal-bedded limestone at a low angle. This zone of weakness may have already been active at the time of the limestone sedimentation and may have worked as a trap for fossils. The stratigraphic lower part (compared to the surrounding limestone beds) of this horizon bears big Halorites cf. ramsaueri embedded in micritic red limestone which was tectonically stressed. In the stratigraphic younger part of this horizon, compared to the normal-bedded surrounding limestone beds, sparitic fissure filling is given in which abundant small ammonoids and gastropods are embedded. According to the occurrence of scarce Sagenites sp. small catenate Halorites and small Hydrozoans, this sparitic part of the fissure filling dates into the subzone IV (after Tatzreiter). Fig.18 Cross-section of a Rhacophyllites neojurensis QUENST. In situ picture from the white sparitic filled stratigraphic upper part of the fissure. Natural size of the picture ca.30x25cm The left side of the picture shows how unspectacular the weathered rock looks, although the mossy vegetation has been removed before by hand. Fig.19 Gastropoda and Halorites-core (1cm), embedded in white calcite. Fig. 20 Slab with Steinmannites hoernesi HAUER, Paracladiscites multilobatus BRONN, Arcestes sp., Placites sp. und Leislingites sp., within white calcite embedded red limestone lithoclasts of the stratigraphic upper part of the fissure. Slab size is 16cm Fig.21 Visible Halorites sp. end body chamber from the stratigraphic lower part of this fissure. Fig.22 Block from the tectonically stressed area of this fissure. Well visible are the calcitically healed slip movements in this rock which show us a "frozen" moment during the lithification of this limestone. Now to the aforementioned talus block of an historical location. After the first blow of the hammer a Halorites was visible. By finding an Amarassites cf. semiplicatus HAUER I was able to date the fauna of this block into the Subzone III afterTatzreiter. Fig.23 Amarassites cf. semiplicatus HAUER (5cm) from the above mentioned talus block of an historical location. Fig.24 Halorites sp., freshly split talus block. Natural picture size ca.20cm At the end of my report some pictures of another Alaunian 3 Fauna. From this location I have less material. The faunal composition differs a little bit from the above mentioned locations. New to this location is cf. Parajuvavites mercedis MOJS. and cf. ?Acanthothetidites sp. Fig.25 Slab from this Alaunian fissure with cf. ? Acanthothetidites sp, („thorned"Ammonite on top, 3cm) Fig.26 Paracladiscites multilobatus BRONN, Arcestes sp., Parajuvavites cf. mercedis MOJS.(ribbed ammonite) Size of slab ca. 10cm Fig.27 Matrixrock of this location Natural size on picture ca. 35cm I hope you have enjoyed this report about my favourite collecting area. Unfortunly I cannot load up graphics. Maybe it is possible and I only do not know how to do this. Maybe somebody can help me in this case. A special thank is given to Fossil forum member "Ludwigia" for correcting my uncivil kind of English. Best regards Andreas Literature: DIENER, C.: Fauna of the Tropites-limestone of Byans. In: Himalayan Fossils, Palaeontologia Indica,(ser.15) 5/1, 1-201, Calcutta 1906 KRYSTYN, L. Zur Ammoniten und Conodonten-Stratigraphie der Hallstätter Obertrias(Salzkammergut, Österreich), Verh.Geol. B.-A., Wien 1973 KRYSTYN, L., SCHÄFFER, G. & SCHLAGER, W. (1971b): Der Stratotypus des Nor.- Annales Inst. Geol. Publ. Hungar., 54, 2, 607-629, 7 Abb., Budapest MOJSISOVICS, E. 1893: Die Cephalopoden der Hallstätter Kalke, Abhandlungen der Kaiserlich-Königlichen Geologischen Reichsanstalt, II Band, Wien 1893 MOJSISOVICS, E. 1896: Beiträge zur Kenntniss der obertriadischen Cephalopoden Faunen des Himalaya, Denkschriften der Kaiserlichen Akademie der Wissenschaften Mathematisch–naturwissenschaftliche Classe, 63, 575–701. Wien 1896, TATZREITER, F. 1981, Ammonitenfauna und Stratigraphie im höheren Nor(Alaun, Trias) der Tethys aufgrund neuer Untersuchungen in Timor, Denkschr. Österr. Akad. Wiss., math.-naturwiss. KI., 121, Wien 1981, Springer Verlag TATZREITER, F. 1985. Zur Kenntnis der obertriadischen (Nor; Alaun, Sevat) trachyostraken Ammonoideen Jb. Geol. B.-A. ISSN 0016-7800 Band 128 Heft 2 S.219-226 Wien, Oktober 1985, 8 Abbildungen TATZREITER,F. 1984: Bericht über paläontologische Untersuchungen in Hallstätterkalken auf Blatt 76 Wr. Neustadt und 96 Bad Ischl. - Jb. Geol. B.-A., 128/2, Wien 1985 TOZER, E. T. 1994. Canadian Triassic ammonoid faunas. Geological Survey of Canada Bulletin, 467,1–663.
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  • MikeR

    The End Of My Pliocene Project

    By MikeR

    When I began this blog late in 2010, my intention was to report on recent field trips however, with the exception of one excursion each into the Upper Miocene, Lower Pliocene and the Calabrian Pleistocene, all of my posts have concentrated on the Upper Pliocene of the US Atlantic and Gulf coastal plains. I already had an extensive collection of Florida Upper Pliocene invertebrates that I had collected while a resident of the state in the late 80s and early 90s. The fossils from these beds are contemporaneous with the Zone 2 Yorktown beds of Virginia and North Carolina that I began collecting in the early 2000s, the Duplin Formation that I collected in 2010 and several trips to Jackson Bluff localities in the Florida panhandle in 2011. These more recent collecting endeavors required a reassessment of the identification of my Florida collection due to a better recognition on my part of modern thoughts on speciation and from working with paleontologists who research these deposits. Also I began rejecting non-peer reviewed books and guides geared toward amateurs which exhibited sloppy and unsubstantiated research. In an effort to free display space I began cross-referencing species from different formations to compile at least what I believe is very accurate species identifications and to place the best example of each species regardless of formation within my display cabinets (fig. 1 & 2). Figure 1. Upper Pliocene (Piacenzian) Bivalvia Eastern United States. Figure 2. Upper Pliocene (Piacenzian) Gastropoda Eastern United States. The attached species list represents the completion of my Pliocene project. Unlike my previous lists which concentrated on the mollusks from particular sites and formations, the 16 page document below is a compilation of all Eastern United States Piacenzian fossils in my collection both vertebrate and invertebrate. The ability to observe different species geographically has led to changes that can be seen if comparing mollusks in the list below to those noted from my previous posts. I have eliminated species which were obviously the same but named differently based upon the regional description of the molluscan fauna by earlier research. The list is not meant to be comprehensive of these deposits, but more of a guide of what can be found. Although my collection is strong in Sarasota area Pinecrest, Jackson Bluff Formation and Zone 2 Yorktown, it is very weak in Pinecrest fauna from the coral reef facies near Miami and the Kissimmee River area, weak in the Duplin Formation (only two localities sampled), and almost absent other than a few trades from early Piacenzian faunas from the Raysor and Goose Creek Formations of the Carolinas. For a more extensive list of species from this period of time I would refer those interested in mollusks to Campbell (1993) and for Florida vertebrates to Hulbert (2001). Piacenzian Fauna List_Reagin.pdf The systematics of the specimens listed are by those fields that I find the most useful in query searches within my Access database and for the most part are as follows: Phylum, Class, Order, Family, Genus, Species, and Subspecies. In stating the distribution of each species, only the formation is noted not the individual members of the Yorktown and Tamiami Formations. Abbreviations used are Yorktown (Y), Duplin (D), Jackson Bluff (J), Tamiami (T) Chowan River (C ), Goose Creek (G) and Raysor (R ). For those taxa which are near to another cf. (similar to) was used. Less specific affinity (aff.) as well as species undetermined (sp.) are designated. The reasoning behind classification I used is addressed in the notes section below. NOTES Algae. A single species of calcareous algae was found in the limestone facies (Ochopee) of the Tamiami Formation which could not be identified to genus or species. Bryozoa. The identification of bryozoa is highly specialized requiring microscopic identification of various feeding structures. Due to a lack of references and interest I identified most as bryozoa species. Anthozoa. Eleven species of coral were collected; almost all of which are from the Pinecrest. The exception is the ubiquitous Septastrea marylandica which led a commensal lifestyle by growing on hermit crab inhabited gastropod shells. The other coral outside the Pinecrest was Septastrea crassa found near Williamsburg, Virginia which I obtained with a collection of Zone 2 Yorktown fossils in a trade from the 80s. Since I did not collect it personally and have not found this particular species at any of the numerous Zone 2 sites that I have collected over the past decade I have designated it as questionable from the Yorktown (Y?). Brachiopoda. Only a single Upper Pliocene brachiopod is listed. Discinisca lugrubris is a geologically wide ranging species found from the Lower Miocene to the Upper Pliocene colder water Bed 11 of the Pinecrest Member of the Tamiami Formation and the Jackson Bluff Formation. Mollusca. Since Piacenzian deposits are known world wide for their shell beds, it stands to reason that mollusks should dominate. The list contains 244 species and subspecies of bivalves, 370 of gastropods and 6 scaphopods. In general, the warmer the water, the higher is gastropod diversity. The list shows that bivalves are wide ranging and less so with gastropods where many more were found only in the warmer water Tamiami Formation. Aragonitic shells do not preserve well in carbonate environments and are often difficult to identify to species. Those shells from the Ochopee Member of the Tamiami Formation that were preserved as internal casts that I felt were probably represented in Pinecrest were not listed separately (i.e. Ficus sp. Internal cast from the Ochopee is probably Ficus jacksonensis from the Pinecrest). I followed the systematics of Turgeon et. al. (1998) which Roger Portell Director, Division of Invertebrate Paleontology of the Florida Museum of Natural History uses for the mollusks in the Florida Paleontology Society publications. This has led to some interesting changes in classification of gastropods within my collection. In a previous post to the forum, I had mentioned that at some point the subgenera of the family Turritellidae had been reclassified to genera. As stated by Turgeon concerning several recent species that were reclassified in this manner “We do not know the source of this reclassification nor have we seen evidence of subsequent acceptance...” therefore I reclassified all genera in Turritellidae back to Turritella with the exception of valid Vermicularia. The most drastic change in classification had to be with members from the families Turridae, Drillidae, and Conidae. I originally classified all turrids in Turridae by older systematics based solely on shell characteristics. I have known for awhile that at some point the family had been split based upon internal structure of the animal itself and DNA studies. What I did not know was that some of those species had been reclassified as Conidae. Turgeon noted that the study was controversial but was supported by anatomical and radular data and also stated that the affected subfamilies would be better suited in their own family. It was difficult for me to classify genera Glyptostoma and Cythara as Conidae, but I did so since I committed to using Turgeon. Cirripedia. Barnacles were more diverse in the Eastern US Upper Pliocene than today but much like bryozoa their specific identification is difficult. Factors for species id include the tubular structure of the outer wall and the internal plates that protect the animal. I feel that most of my identifications are correct however some are based upon morphological features of the outer shell and geographical range and thus might not be accurate. Decapoda. Crabs are a common component of shell beds, however due to the formation of the beds by winnowing, crabs are rarely preserved intact. The majority of crab finds are as isolated legs, claws, and occasional carapaces. Very little study has been made of Pliocene crabs, but most notable are publications by Rathbun (1935) who identified a wide geographical range of species and those of Florida by Portell and coauthors (2002, 2004). The crabs of the Yorktown Formation are not characterized and in many cases at generic level I used similar to reference (Cf.) which like Cirripedia does not follow proper identification rules. Echinoids. Much like crabs, disarticulated echinoid remains can be common in shell beds. In limestone however, because of their calcitic tests and gentle conditions in carbonate environments, echinoids can be preserved intact. I have not collected in the Raysor and Goose Creek Formations but I did receive echinoids from these deposits in trades from the 90s. At one point both of these units were considered members of the Duplin Formation. This has led to designation in the list (D/R) meaning that the original label listed Duplin Formation but due to the attached calcareous matrix, I believe that the specimens are from the Raysor. Vertebrates. Those collectors who have been fortunate to collect at the PCS/Lee Creek Mine are well aware of the rich vertebrate fauna found in the Yorktown Formation. The Yorktown however is divided into two different units—Zone 1 Lower Pliocene (Zanclean) and Zone 2 Upper Pliocene (Piacenzian). One of the distinguish features of these two zones is the richness of vertebrates in Zone 1 compared to their very sparse nature in Zone 2. Vertebrates during this interval are only common in Pinecrest Beds 4 and 11 and a bone layer in Bed 3 consisting of a mass die off of cormorants during a red tide which I never collected. Marine vertebrates can also be found within the Jackson Bluff Formation but not as plentiful as the previously described beds. Redeposited vertebrate remains are found in the Upper Pliocene of the Carolinas and Virginia and are not included in my list. These include teeth of the Cretaceous sharks Squalicorax kaupi and Scapanorhynchus texanus that I have found in the Duplin Formation and vertebrates from the lag deposit found at the contact between the Upper Cretaceous Black Creek Group and Zone 2 Yorktown Formation at my locality 1012 which probably represented concentrated bones and teeth from the Lower Pliocene and Upper Miocene. Upper Pliocene vertebrate remains besides bony fish, shark and ray in my collection include one marine turtle, one land tortoise, a capybara, a walrus, and a dugong. I classified large whale remains as Mysticeti and smaller remains as Odontoceti dolphin although there could be crossover. REFERENCES Numerous references were used and I have them listed according to those for identification or taxonomy and those that I used in writing about the geology or ecology of the deposits described within my blog. In addition to the below publications, I found Greta Polites Fossil Muricidae Website (http://glpolites.us/murex/index.htm) to be invaluable in eliminating synonymous species. My only deviation from her list was with Ecphora which I only recognized two species, E. quadricostata and bradlyae. Identification Campbell, Lyle. 1975. Check List of Marine Pliocene Mollusks of Eastern North America in Plio-Pleistocene Faunas of the Central Carolina Coastal Plain. Geologic Notes (South Carolina Division of Geology) Vol. 19, No. 3. Campbell, Lyle. 1993. Pliocene Molluscs from the Yorktown and Chowan River Formations in Virginia. Virginia Division of Mineral Resources Publication 127. Dall W.H. 1890-1903. Contributions to the Tertiary Fauna of Florida, with Especial Reference to the Miocene Silex-Beds of Tampa and the Pliocene Beds of the Caloosahatchie River, Part I: Pulmonate, Opisthobranchiate and Orthodont Gastropods, Transactions of the Wagner Free Institute of Science of Philadelphia 3(1-VI). Gardner, J. A. 1944. Mollusca from the Miocene and Lower Pliocene of Virginia and North Carolina: Part 1. Pelecypoda, United States Geological Survey Professional Paper 199-A: iv, pages 1-178, plates 1-23 Gardner, J. A. 1948. Mollusca from the Miocene and Lower Pliocene of Virginia and North Carolina: Part 2. Scaphopoda and Gastropoda, United States Geological Survey Professional Paper 199-B: iv, pages 179-310, plates 24-38, [iii] Gardner, J. A. and T.H. Aldrich. 1919. Mollusca from the Upper Miocene of South Carolina: with Descriptions of New Species. Proceedings of the Academy of Natural Sciences of Philadelphia 71: pages 17-53. Gibson, Thomas G. 1987. Miocene and Pliocene Pectinidae (Bivalvia) from the Lee Creek Mine and Adjacent Areas in Geology and Paleontology of the Lee Creek Mine, North Carolina, II. Smithsonian Contributions to Paleobiology No. 61. Hendricks, Jonathan. 2008. The genus Conus (Mollusca: Neogastropoda) in the Plio-Pleistocene of the southeastern United States, Bulletins of American Paleontology 375. Kohno, Naoki and Ray, Clayton E. 2008. Pliocene Walruses from the Yorktown Formation of Virginia and North Carolina, and a Systematic Revision of the North Atlantic Pliocene Walruses in The Geology and Paleontology of the Lee Creek Mine, North Carolina, IV. Virginia Museum of Natural History Special Publication No. 14. Mansfield, W.C. 1930. Miocene Gastropods and Scaphopods of the Choctawhatchee Formation of Florida, Florida Geological Survey Bulletin 3, 189 pages. Mansfield, W.C. 1931. Some tertiary mollusks from southern Florida. Proceedings of the United States National Museum, v. 79. Mansfield, W.C. 1931. Pliocene Fossils from Limestone in Southern Florida in Shorter Contributions to General Geology, USGS Professional Paper 170, 11 pages. Mansfield, W.C. 1932. Miocene Pelecypods of the Choctawhatchee Formation of Florida, Florida Geological Survey Bulletin 8, 233 pages. Mansfield, W.C. 1936. Stratigraphic Significance of Miocene, Pliocene, and Pleistocene Pectinidae in the Southeastern United States, Journal of Paleontology, Vol 10, No. 3, 24 pages. Mansfield, W.C. 1939. Notes on the Upper Tertiary and Pleistocene Mollusks of Peninsular Florida, Florida Geological Survey Bulletin 18, 128 pages. Mansfield, W.C., 1943 [1944]. Stratigraphy of the Miocene of Virginia and the Miocene and Pliocene of North Carolina in Gardner, Julia ed. Mollusca from the Miocene and Lower Pliocene of Virginia and North Carolina. USGS Professional Paper 199A, p. 1-19. Hollister, S.C. 1971. New Vasum Species of the Subgenus Hystrivasum. Bulletins of American Paleontology 262. Olsson, A.A. 1967 (1993 Reprint). Some Tertiary Mollusks from South Florida and the Caribbean, Originally - Bulletins of American Paleontology 54(242), The Paleontological Research Institute Special Publication 19: pages 11-75, 9 plates Olsson, A.A., and A. Harbison. 1953 (1990 Reprint). Pliocene Mollusca of Southern Florida with Special Reference to Those from North Saint Petersburg, with special chapters on Turridae by W.G. Fargo and Vitinellidae and Fresh-water Mollusks by H.A. Pilsbry, The Academy of Natural Sciences of Philadelphia Monographs 8, The Shell Museum and Educational Foundation, 457 pages, 65 plates Olsson, A.A., and R.E. Petit. 1964. Some Neogene Mollusca from Florida and the Carolinas, Bulletins of American Paleontology 47(217): pages 509-574, plates 77-83 Olsson, A.A., and R.E. Petit. 1968 (1993 Reprint). Notes on Siphocypraea, Originally - Special Publication 9, The Paleontological Research Institute Special Publication 19: pages 77-88. Petuch, Edward J. 1994. Atlas of Florida Fossil Shells (Pliocene and Pleistocene Marine Gastropods). Chicago Spectrum Press. Portell, Roger W. and Craig W. Oyen. June 2002. Pliocene and Pleistocene Echinoids. Florida Fossil Invertebrates Part 3, 30pp. Portell, Roger W. and Jeffery G. Agnew. February 2004. Pliocene and Pleistocene Decapod Crustaceans. Florida Fossil Invertebrates Part 4, 29 pp. Portell, Roger W. November 2004. Eocene, Oligocene and Miocene Decapod Crustaceans. Florida Fossil Invertebrates Part 4, 29 pp. Portell, Roger W. and B. Alex Kittle. December 2010. Mollusca, Bermont Formation (Middle Pleistocene). Florida Fossil Invertebrates Part 13, 40 pp. Rathbun, Mary J. 1935. Fossil Crustacea of the Atlantic and Gulf coastal plain. Geological Society of America. Special papers; no. 2. Tucker, H.I. and Druid Wilson. 1932. Some new or otherwise interesting fossils from the Florida Tertiary. Bulletins of American paleontology; v. 18: no. 65. Tucker, H.I. and Druid Wilson. 1933. A second contribution to the Neogene paleontology of South Florida. Bulletins of American paleontology; v. 18: no. 66. Tuomey, M., and F.S. Holmes. 1855-1856 (1974 Reprint). Pleiocene Fossils of South-Carolina: Containing Descriptions and Figures of the Polyparia, Echinodermata and Mollusca, Original pages 1-30 and plates 1-12 published in 1855, Original pages 31-152 and plates 13-30 published in 1856, The Paleontological Research Institution Special Publication 12: xvi, 152 pages, 30 plates, [addendum] Ward L.W. and Blackwelder, B.W. 1975. Chesapecten, a New “Genus of Pectinidae (Mollusca: Bivalvia) from the Miocene and Pliocene of Eastern North America. USGS Professional Paper 861. Whitmore, Frank C. Jr and Kaltenbach, James A. 2008. Neogene Cetacea of the Lee Creek Phosphate Mine, North Carolina in The Geology and Paleontology of the Lee Creek Mine, North Carolina, IV. Virginia Museum of Natural History Special Publication No. 14. Weisbord, Norman E. 1966. Some late Cenozoic cirripeds from Venezuela and Florida. Bull. Amer. Paleont., vol. 50, no. 225, pp. 1-145, pls. 1-12. Weisbord, Norman E. 1974. Late Cenozoic Corals of South Florida. Bulletins of American Paleontology vol. 66, no. 285. 544 pp. Zullo, Victor A., 1992. Revision of the balanid barnacle genus Concavus Newman. Supplement to Journal of Paleontology, v. 66, no. 6, pt. II. Zullo, Victor A. and Portell, Roger W. 1993. Paleobiogeography of the Late Cenozoic Barnacle Fauna of Florida in The Neogene of Florida and Adjacent Regions, Florida Geological Survey Special Publication No. 37. Paleoecology Allmon, Warren D. 1992. Whence Southern Florida’s Plio-Pleistocene shell beds? Plio-Pleistocene Stratigraphy and Paleontology of Southern Florida, Florida Geological Survey Special Publication No. 36. Allmon, Warren D; Rosenberg, Gary; Portell, Roger W.; and Schindler, Kevin S. 1993. Diversity of Atlantic Coastal Plain Mollusks since the Pliocene. Science, vol. 260:1626-1629. Allmon, Warren D; Spizuco, Mathew P. and Jones, Douglas S. 1995. Taphonomy and paleoenvironment of two turritellid-gastropod-rich beds, Pliocene of Florida. Lethaia, vol. 28:75-83. Allmon, Warren D; Emslie, Steven D.; Jones, Douglas S.; and Morgan, Gary S. 1996. Late Neogene Oceanographic change along Florida’s West Coast: Evidence and mechanisms. The Journal of Geology, vol. 104:143-162. Christie, Max. 2009. Ecological Interactions Across a Plio-Pleistocene Interval of Faunal Turnover: Naticid Cannibalism North and South of Cape Hatteras, North Carolina. Departmental Honors in Interdisciplinary Studies Thesis, The College of William and Mary. Geary, Dana H. and Allmon, Warren D. 1990. Biological and Physical Contributions to the Accumulation of Strombid Gastropods in a Pliocene Shell Bed. Palaios vol. 5:259-272. Jones, Douglas S and Allmon, Warren D. 1999. Pliocene marine temperatures on the West Coast of Florida: Estimates from mollusk shell stable isotopes In J.H. Wrenn, J.-P. Suc, and S.A.G. Leroy, eds., The Pliocene: Time of Change. American Association of Stratigraphic Palynologists Foundation, Dallas, Texas, pp. 241-250. Molnar, Peter. 2008. Closing of the Central American Seaway and the Ice Age: A critical review. Paleoceanography Volume 21. Petuch, Edward J. 2004. Cenozoic Seas. CRC Press. Petuch, Edward J. 2007. The Geology of the Everglades and Adjacent Areas. CRC Press. Schmidt, D. N., 2007. The closure history of the Panama Isthmus: Evidence from isotopes and fossils to models and molecules. In: Williams, M., Haywood, A. M., Gregory, J. F., and Schmidt, D. N. Eds.), Deep time perspectives on climate change - marrying the signal from computer models and biological proxies. Geological Society of London, London. Biostratigraphy Campbell, Kenneth M. 1985. Alum Bluff Liberty County, Florida. Florida Geological Survey Open File Report 9. Ketcher, Kathleen. 1992. Stratigraphy and Environment of Bed 11 of the "Pinecrest" Beds at Sarasota, Florida in Plio-Pleistocene Stratigraphy and Paleontology of Southern Florida, Florida Geological Survey Special Publication No. 36. Means, Harley. 2002. Introduction to the Geology of the Upper Apalachicola River Basin in Geologic Exposures Along the Upper Apalachicola River. Southeastern Geological Society Field Trip Guidebook 42. Missimer, Thomas M. 1992. Stratigraphic relationships of sediment facies within the Tamiami Formation of Southwest Florida: Proposed intraformational correlations. Plio-Pleistocene Stratigraphy and Paleontology of Southern Florida, Florida Geological Survey Special Publication No. 36. Petuch, E.J. 1982. Notes on the molluscan paleontology of the Pinecrest Beds at Sarasota, Florida with the description of Pyruella, a stratigraphically important new genus: Proceedings of the Academy of Natural Sciences of Philadelphia, v. 134, p. 12–30. Ward, Lauck W. 1992. Tertiary Molluscan Assemblages from the Salisbury Embayment of Virginia. Virginia Journal of Science, Volume 43, no. 1B. Ward, Lauck W. 1992. Diagnostic Mollusks from the APAC Pit, Sarasota, Florida in Plio-Pleistocene Stratigraphy and Paleontology of Southern Florida, Florida Geological Survey Special Publication No. 36. Ward, Lauck W. 1993. Pliocene Stratigraphy and Biostratigraphy, Virginia to Florida in The Neogene of Florida and Adjacent Regions, Florida Geological Survey Special Publication No. 37. Ward, Lauck W. 2008. Synthesis of Paleontological and Stratigraphic Investigations at the Lee Creek Mine, Aurora, NC (1958-2007) in The Geology and Paleontology of the Lee Creek Mine, North Carolina, IV. Virginia Museum of Natural History Special Publication No. 14. Yon, J. William. 1965. Adventures in geology at Jackson Bluff. Florida Geological Survey: Special publication 14. Systematics Hulbert, Richard C. (ed.). 2001. The Fossils Vertebrates of Florida. University Press of Florida. Turgeon, D.D. et al. 1998. Common and scientific names of aquatic invertebrates from the United States and Canada: mollusks. Second edition. American Fisheries Society Special Publication. No. 26. 526 pp.
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