A long, hot day with Cretaceous phosphorites in the Negev

July 3rd, 2013

OscarHawarimOutcrop070313MITZPE RAMON, ISRAEL–This was one of Oscar’s big field days. He is shown above at his first exposure of the phosphatic zone of the Mishash Formation (Campanian, Upper Cretaceous) exposed at Wadi Hawarim (N 30.84423°, E 34.75742°). We see here the entire section from the top of a phosphate-cemented conglomerate to the base of the overlying Ghareb Formation (the brown marls at the top of the image). Oscar is working to understand the complicated stratigraphy and origin hypotheses for these phosphorites. You may be able to make out some of the red ribbons we placed while measuring the section.

HawarimMishash070313This is another view of the Mishash phosphorites at Wadi Hawarim, with the Ghareb Formation in the upper left. We have six measured, sampled and described members in just under eight meters of section here. The phosphates are finely disseminated in some of the chalky units and bound up in a layer of nodules at the top.

ParticleDinosaur070313A conglomerate within the phosphate zone of the Mishash has an interesting collection of clasts, including this large chunk of reptile bone, possibly from a dinosaur. (Which is what we always say about large bone bits from the Mesozoic!)

SharkTeeth070313While Oscar and I worked on his measured section, Lizzie and Steph looked for shark teeth in the conglomerate unit. They did very well. Above is a sample of what they found. So Andrew Retzler — any ideas about what kind of sharks are represented by these tiny teeth? It looks like a small tooth in the lower row is Squalicorax kaupi.

RotemAmfertNegevMeeting070313Near the end of the day we went to one of the phosphate mine and enrichment plant owned and operated by Rotem Amfert Negev Ltd. This was a treat for Oscar who has strong interests in the economic geology of mining. We heard an excellent presentation by the chief geologist of the mine about the value of phosphate, the main markets for the their products, and the geological setting of these Negev phosphorites.

PhosphateMine070313Afterwards we visited the active part of the mine, shown above. Since about 2005 the mine has been restoring land as fast as it mines it. On the right is the working face of the mine, the white unit on the floor has most of the phosphate in it and is being ground up by the vehicle slowing moving across it. On the far left are piles of overburden and “interburden” (unusable material between the three phosphate-rich layers) ready to fill in the pit once the phosphorite is removed. We also saw those parts of the area where the original topography and (they hope) cryptobiotic top soil has been restored.

It was a good day, though a long one. Tomorrow we will celebrate the Fourth of July with yet another Negev work day. Maybe we’ll have a special American-themed dinner afterwards.

Fossil collecting under a desert sun

July 2nd, 2013

GroupCollecting070213MITZPE RAMON, ISRAEL–Today the Wooster Geologists in Israel collected fossils from the Matmor Formation in Makhtesh Gadol. It was time to begin assembling data for Lizzie Reinthal’s and Steph Bosch’s Independent Study projects, and to follow up on some projects I have going in this Middle Jurassic set of fossiliferous marls and limestones. We do all our work as a team so that everyone is helping with everyone else’s project at some point. In the image above we have everyone at work picking up fossils at one outcrop near the center of the makhtesh (N 30.93369°, E 34.97588°, to be exact).

LizzieCollecting070213Lizzie is working on crinoid taphonomy, which we’re approaching in a very systematic way. She laid out individual square-meter boundaries on her fossiliferous exposures and collected every bit of crinoid present, from single columnals (the disks that make up a crinoid stem) to partial calices (the crowns or “heads” where the feeding arms were attached). She even seived the sediment to get a sample of small fragments like those from the arms. This way we can assess how the crinoids were disarticulated and tossed about on the seafloor, and whether their stems had some characteristic detachment horizons.

MatmorMakhteshGadol070213_585We are here in the Matmor Hills looking south towards the distant wall of the makhtesh. Two geologists are collecting from a yellowish marl. What do you think that small red dot is in the center?

OscarCollecting070213Why it is Oscar Mmari showing his flair for innovation! He brought the umbrella not for rain (that’s not going to happen here in July, for sure) but just for this. He isn’t much for hats, and we all must admit he had the best shade all day.

StephCollecting070213And here is Steph Bosch carefully collecting tiny little specimens — hoping, hoping some will be encrusted by bryozoans. (None yet, but the best sites are yet to come.)

BittenSpines070213So what did we find? I can show you only a few things because fossil photography in a hotel room is more difficult than you might imagine. (Can you guess what background I’m using?) At one location in the Matmor Formation we collected every exposed echinoid spine in an attempt to statistically determine how many were bitten by some sort of predator. You can see that the spines displayed above have been chomped, probably by some sort of fish. Spines like these were part of an earlier Fossil of the Week post.

Nautiloid070213Yoav found this  nautiloid in subunit 52 of the Matmor Formation. The entire shell, including the septa (walls dividing the chambers), has been replaced with a fine-grained calcite. What are the two holes apparently punched through the shell? They could be just erosion, but I like to think they’re bite marks from some toothy reptile! [Added note: I think I've just identified this nautiloid. It has a distinctive groove on the venter (not visible here) which may place it in the genus Cymatonautilus. This genus lived only a short time (latest early to middle Callovian Stage of the Jurassic Period) and is found along the shallow shelf of the Tethys. Right interval, right place.]

Field reconnaissance in the northern Negev of Israel

July 1st, 2013

1FoldedPhosphates070113MITZPE RAMON, ISRAEL–This morning Team Israel 2013 met our friend Yoav Avni, a geologist with the Geological Survey of Israel (GSI), and we traveled north to our field localities. We did a survey of the sites so that we could put together an efficient schedule for our work over the next two weeks. We had a four-wheel drive vehicle from the GSI so we could get to places our little Budget rental car could only have nightmares about.

The first locations were for Oscar Mmari’s Cretaceous phosphorite work. The outcrop pictured at the top of this entry is on the east side of Makhtesh Gadol (N 30.93657°, E 035.03312°). We are looking toward the west at an incredibly asymmetric limb of a syncline. In the upper part of the exposure you can see the rocks dipping almost vertically, yet in the foreground they are nearly horizontal. They make an almost 90° bend. The Mishash Formation phosphatic zone is partly exposed as the white rocks along the side of the wadi. The phosphorites here are very thick and chalky.

2MishhashPhosphates070113A second phosphorite exposure for Oscar is in Wadi Havarim (N 30.84269°, E 34.75509°) not too far north of Mitzpe Ramon. The top of the cherty portion of the Mishash Formation is on the left in the middle; the light-colored units above are phosphorites. In the background is Nahal Zin, a deep valley formed by water draining north into the Dead Sea. The base level of the Dead Sea is so low that the wadis leading to it are rapidly downcut.

3OscarPhosphorite070113Here is Oscar getting is first look at the phosphorites at Wadi Havarim. Later this week we will measure at least one section at each locality and take plenty of samples for thin-sectioning and scanning electron microscopy.

4TraceFossil070113Steph Bosch’s hand gives us a scale for a nice set of trace fossils found in the phosphorite at Wadi Havarim. These look like callianassid shrimp burrows to me. We found some preserved as burrow-fills with apparent fecal pellets forming the outer walls. If true then the trace fossil ichnogenus is Ophiomorpha. This is a good indicator of shallow water.

5PhosphateSign070113We also briefly visited two phosphate mining sites east of Makhtesh Gadol. One has this helpful sign outside describing the geology of these deposits. The phosphorites are shown in yellow. Note that they formed in two synclines, both highly asymmetrical (as shown in our top photo).

6PhosphateMinedValleyWe viewed one phosphate mine where virtually the whole valley has been quarried, producing enormous piles of waste materials. Reclaiming mined terrain like this is especially difficult in this arid climate. Oscar will not only be looking at the geology of these phosphate deposits, but also the economics of mining, which now includes remediation and controls on emissions and water pollution.

7MatmorCollectingFirstDay070113After lunch we drove down into the center of Makhtesh Gadol and plotted out future localities for Steph and Lizzie to do their work in the Matmor Formation. (The above site is at N 30.93837°, E 34.97907°.) I’ve been to these sites many times with students, so it was relatively easy to make our plan for collecting crinoids and encrusting bryozoans tomorrow and next week.

8NabateanCistern070113Finally, no fieldwork in Israel is complete without a touch of archaeology. Yoav took us into a Nabatean cistern and showed us the clever engineering (and strategic plastering) necessary to make this hand-cut cavern into a water trapping and storage facility. This cistern is cut into the Menuha Formation, a chalk unit very familiar to Andrew Retzler (’11). This cistern was originally made sometime between 100 BCE and 100 CE. After the nabateans it was used by the Romans, Byzantines and Arabs. It was last used by Israeli pioneers over 60 years ago.

Tomorrow we return to Makhtesh Gadol and work in the hot sunlight filling collecting bags with tiny bits of crinoids and assorted encrusters. We’ve had a very good start.

Wooster Geologists return to the Negev

June 30th, 2013

LizzieOscarSteph063013MITZPE RAMON, ISRAEL–These are the shining faces of Team Israel 2013 of the Wooster Geology program. From the left is wind-challenged Lizzie Reinthal (’14) from Ohio, Oscar Mmari (’14) from Tanzania, and Steph Bosch (’14) from Pennsylvania (and soon to be an Arizonan). We arrived this afternoon in our destination town of Mitzpe Ramon in the Negev Highlands of southern Israel. This is our first geological stop: a short walk from the hotel to the northern rim of the magnificent Makhtesh Ramon, a deep erosional feature often called the “Grand Canyon of Israel”. If you look back in our Israel blog entries (such as this one) you’ll see this is a traditional setting for our first images! (And the students get their first geological examination on an Israeli outcrop.)

We are in Israel for two weeks pursuing research as part of Wooster’s Senior Independent Study program. Lizzie will be looking at the taphonomy of crinoids in the Jurassic Matmor Formation, Oscar will be studying the origin and economic value of an extensive set of Cretaceous phosphorites, and Steph will be studying rare but important bryozoan fossils from the Matmor Formation, which was deposited near the equator during the Jurassic.

Getting to this spot in the middle of the desert took lots of planning. (Thanks, Suzanne Easterling and Patrice Reeder!) Oscar flew to Tel Aviv from Tanzania via Ethiopia a few hours before us. I was worried about his connections and getting through immigration, but it worked out splendidly — Oscar was there to greet us as we emerged from the arrivals gate. We then packed into a rental car and drove south about three hours to Mitzpe Ramon. The weather is excellent — far cooler than the deserts today in the southwestern USA!

Wooster’s Fossil of the Week: A terebratulid brachiopod from the Middle Triassic of southern Israel

April 14th, 2013

Coenothyris oweni Anisian 041013 585Sure, I could have picked a pristine shell from our collection, but I like the rugged character of this one. It is the terebratulid brachiopod Coenothyris oweni Feldman, 2002, from the lower Saharonim Formation (Middle Triassic) of Har Devanim, southern Israel. I picked it up, along with a dozen others, during our 2010 Israel expedition.

Above we have a dorsal view of this brachiopod. The posterior is at the top, anterior at the bottom. The round hole is the pedicle opening in the ventral valve. (The pedicle is a fleshy stalk the brachiopod uses to attach to a substrate.) As with all brachiopods, you can see the bilateral symmetry of the shell with the plane perpendicular to the hinge between the valves. Terebratulids are still around.

Saharonim061010

The layered units at the top of this ridge of Har Devanim are the lower part of the Saharonim Formation (Anisian, Middle Triassic). Micah Risacher (’11) is just visible.

CoenothyrisBedding061010

Coenothyris oweni was named in 2002 by my friend Howie Feldman. He also wrote a 2005 paper on the paleoecology of this species in the Saharonim Formation of southern Israel. The brachiopods are sometimes found in obrution deposits, meaning they were buried alive by storm-driven sediments (see above).

Combined_Douville

The genus Coenothyris was named by Joseph Henri Ferdinand Douvillé in 1879 (above as a young man and older). He was a French paleontologist and geologist who worked first as a mining engineer and then a professor of paleontology at the École des Mines (School of Mines). His research took him around the world, but his most prominent papers were on French fossils and geology. In 1881 he became president of the Société géologique de France; in 1907 he was elevated to the Académie des Sciences.

References:

Feldman, H.R. 2002. A new species of Coenothyris (Brachiopoda) from the Triassic (Upper Anisian-Ladinian) of Israel. Journal of Paleontology 76: 34-42.

Feldman, H.R. 2005. Paleoecology, taphonomy, and biogeography of a Coenothyris community (Brachiopoda, Terebratulida) from the Triassic (Upper Anisian-Lower Ladinian) of Israel. American Museum Novitates, no. 3479: 1-19.

Wooster’s Fossil of the Week: Sea urchin bites from the Upper Cretaceous of southern Israel

February 10th, 2013

GnathichnusCenomanian020413_585What you see above is a bit of oyster shell with some curious small gouges in it. The oyster is Ilymatogyra (Afrogyra) africana (Lamarck, 1801) from the En Yorqe’am Formation (Cenomanian) exposed in Hamakhtesh Hagadol, southern Israel. The deep scratches are the trace fossil Gnathichnus pentax Bromley, 1975. As you can just make out in the lower center of the image, the grooves are overlapping series of five-pointed stars. That’s what makes this trace so cool — the stars were made by the unique feeding apparatus of a regular echinoid (sea urchin).
Strongylocentrotus_purpuratus_020313_585This is the business end of the modern sea urchin Strongylocentrotus purpuratus (a preserved specimen in Wooster’s collection). You see here in the center the peristome, which is a circle of plates surrounding the mouth, with the sharp five-sided teeth protruding from the echinoid’s Aristotle’s Lantern. These animals slowly graze across hard substrates, using their teeth to scrape the surfaces for algae, fungi and adherent organisms like diatoms. The biting actions of the Aristotle’s Lantern produce the star-shaped incisions we know as the trace fossil Gnathichnus pentax.

I briefly sampled and studied an exposure of the fossiliferous En Yorqe’am Formation in 2003 during my first visit to Israel. The oyster shells in this unit provide one of the few examples of hard substrate communities in the tropics of the Late Cretaceous. The encrusters include ostreid and spondylid bivalves, the cyclostome bryozoan Stomatopora, and the agglutinating foraminiferan Acruliammina. Borings include those of barnacles (Rogerella elliptica) and sponges (Entobia aff. E. megastoma). There is also a sea urchin present (Heterodiadema lybicum) that was almost certainly the maker of the Gnathichnus pentax traces.

References:

Bromley, R.G. 1975. Comparative analysis of fossil and recent echinoid bioerosion. Palaeontology 18: 725-739.

Wilson, M.A. 2003. Paleoecology of a tropical Late Cretaceous (Cenomanian) skeletozoan community in the Negev Desert of southern Israel. Geological Society of America Abstracts with Programs 35(6): 420.

Wooster’s Fossils of the Week: Episkeletozoans from the Middle Jurassic of Israel

December 30th, 2012

Stomatopora122812Last week I had a delightful research afternoon with my former student Lisa Park Boush, now a professor in the Department of Geology and Environmental Science at The University of Akron, and currently Program Director, National Science Foundation, Sedimentary Geology and Paleontology Program, EAR Division. Lisa also directs an Environmental Scanning Electron Microscope (ESEM) lab in Akron. We worked there with the FEI Quanta 200 microscope looking at encrusters on echinoid fragments from the Matmor Formation (Middle Jurassic) of southern Israel. These encrusters are called episkeletozoans, a five-nickel word meaning that they are animals that encrusted the exteriors of skeletal fragments.

The specimen above is an eroded bryozoan episkeletozoan on the interior of an echinoid coronal fragment. It’s been beat up a bit and partially recrystallized, but we can see enough to identify it as the cyclostome Stomatopora Bronn, 1825.
SpineForam1This is the base of an echinoid spine with a tiny foraminiferan attached to it.
ForamSpine2Here is a close-up of the above foraminiferan. It is probably Placopsilina d’Orbigny, 1850. You can see an apparent aperture looking a bit like a blowhole on the left end top.
LisaSEM122812Above is our hero Lisa running the ESEM. This complicated device uses low vacuum so that we can look at uncoated specimens. We just stuck the specimens onto stubs with conducting tape and placed them in the chamber (on the right). I remember the old days when electron microscopy specimens had to be carefully dried and sputter-coated with gold or carbon. The advent of the ESEM made high quality imaging much easier, and thus more commonly done.

The images we took on this day are part of a larger project describing and interpreting the paleoecology of the Matmor Formation. It is a huge task, but every helpful session like this moves us closer to completion. Thanks, Lisa!

References:

Guilbault, J.-P., Krautter, M., Conway, K.W., and Barrie, J.V. 2006. Modern Foraminifera attached to hexactinellid sponge meshwork on the West Canadian Shelf: Comparison with Jurassic counterparts from Europe. Palaeontologia Electronica 9, Issue 1; 3A:48p; http://palaeo-electronica.org/paleo/2006_1/sponge/issue1_06.htm

Richardson-White, S. and S.E. Walker, S.E. 2011. Diversity, taphonomy and behavior of encrusting Foraminifera on experimental shells deployed along a shelf-to-slope bathymetric gradient, Lee Stocking Island, Bahamas. Palaeogeography, Palaeoclimatology, Palaeoecology 312: 305–324.

Taylor, P.D. and Furness, R.W. 1978. Astogenetic and environmental variation of zooid size within colonies of Jurassic Stomatopora (Bryozoa, Cyclostomata). Journal of Paleontology 52: 1093-1102.

Taylor, P.D. and Wilson, M.A. 2003. Palaeoecology and evolution of marine hard substrate communities. Earth-Science Reviews 62: 1-103.

Walker, S.E., Parsons-Hubbard, K., Richardson-White, S., Brett, C. and Powell, E. 2011. Alpha and beta diversity of encrusting foraminifera that recruit to long-term experiments along a carbonate platform-to-slope gradient: Paleoecological and paleoenvironmental implications. Palaeogeography, Palaeoclimatology, Palaeoecology 312: 325–349.

Wooster’s Fossils of the Week: Shark teeth! (Upper Cretaceous of Israel)

December 2nd, 2012

This week’s set of exquisite fossils is presented in honor of Andrew Retzler (’11) who has just had his Senior Independent Study thesis at Wooster published in the journal Cretaceous Research: “Chondrichthyans from the Menuha Formation (Late Cretaceous: Santonian–Early Campanian) of the Makhtesh Ramon region, southern Israel“. The above beauties are a mix of Scapanorhynchus teeth found in the southwestern portion of Makhtesh Ramon during Andrew’s study in the summer of 2010. We were ably assisted by Micah Risacher and Yoav Avni with these collections.

Andrew identified at least eight shark species and two other fish species in the Menuha Formation around Makhtesh Ramon. Most of the teeth are from a soft yellowish chalk with relatively few other fossils (mostly oysters, echinoids, foraminiferans and traces). They show that the Menuha was deposited in a shallow, open-shelf environment on the flanks of the developing Ramon anticline. So, they not only provide new information about Cretaceous sharks in the Middle East, they help sort out a complex stratigraphic-structural problem.

Well done, Andrew! (Andrew is currently a graduate student at Idaho State University. He is working on the Late Devonian Alamo Impact Event in Nevada with Dr. Leif Tapanila.)

Tooth of the shark Cretalamna appendiculata. Composite photo by Andrew Retzler.

Scapanorhynchus rapax, another shark species. Composite photo by Andrew Retzler.

An elegant Scapanorhynchus texana tooth.

Looking south at one of the productive exposures of the Menuha Formation (shown as the red dot) at Makhtesh Ramon. This is one of those amazing Google Earth images.

Wooster’s Fossil of the Week: A new crinoid species from the Middle Jurassic of southern Israel

November 11th, 2012

About a year ago I showed my good friend Bill Ausich (The Ohio State University) hundreds of crinoid pieces from the Matmor Formation (Jurassic, Callovian) exposed in Hamakhtesh Hagadol, southern Israel. We knew the crinoid represented by all these pieces belonged to the genus Apiocrinites Miller, 1821, but we could not place the species. Bill, crinoid genius that he is, then figured out this was a new species. We now have the pleasure of introducing Apiocrinites negevensis Ausich & Wilson, 2012.

This species of Apiocrinites, the first described from Jurassic tropical latitudes, is distinguished by features in its calyx (or crown or head). A. negevensis has a narrow radial facet and adjacent arms are not in lateral contact. It also has large aboral cup plates. (And it is gorgeous.) In the above image from Figure 1 of our paper, the A. negevensis holotype is shown as 1-3; 1 is a lateral view, radial plate missing from either side of the single preserved radial plate; 2, radial facet; 3, inside of cup with cavity extending to proximale; 4, a partial cup with proximale, one complete and one broken basal plates, and one broken radial plate (note numerous barnacle borings, Rogerella Saint-Seine, 1951, on this specimen).

A holdfast of Apiocrinites negevensis that was attached to the underside of a coral. (From Figure 1 of Ausich and Wilson, 2012.)

Apiocrinites negevensis parts in the  field (Matmor Formation, Hamakhtesh Hagadol, southern Israel). See this post for a discussion of our fieldwork.

The taxonomic category we know as the Crinoidea was established in 1821 by J.S. Miller, who separated the stalked echinoderms from all the others. At the same time he erected the genus Apiocrinites.

Cover of Miller’s 1821 book describing the crinoids, including the new Apiocrinites.

Miller’s (1821) illustrations of Apiocrinites.

References:

Ausich, W.I. and Wilson, M.A. 2012. New Tethyan Apiocrinitidae (Crinoidea; Articulata) from the Jurassic of Israel. Journal of Paleontology 86: 1051-1055.

Feldman, H.R. and Brett, C.E. 1998. Epi- and endobiontic organisms on Late Jurassic crinoid columns from the Negev Desert, Israel: Implications for co-evolution. Lethaia 31: 57-71.

Miller, J.S. 1821. A natural history of the Crinoidea or lily-shaped animals, with observation on the genera Asterias, Euryale, Comatula, and Marsupites. Bryan & Co, Bristol, 150 pp.

Wilson, M.A., Feldman, H.R. and Krivicich, E.B. 2010. Bioerosion in an equatorial Middle Jurassic coral-sponge reef community (Callovian, Matmor Formation, southern Israel). Palaeogeography, Palaeoclimatology, Palaeoecology 289: 93-101.

Wilson, M.A., Feldman, H.R., Bowen, J.C. and Avni, J. 2008. A new equatorial, very shallow marine sclerozoan fauna from the Middle Jurassic (late Callovian) of southern Israel. Palaeogeography, Palaeoclimatology, Palaeoecology 263: 24-29.

Presenting a Jurassic echinoid story on the last day of GSA 2012

November 7th, 2012

CHARLOTTE, NORTH CAROLINA–The last day of a scientific meeting is always less frantic. About half the attendees have left for home, the exhibitors start to give away merchandise so they don’t have to ship it home, and the speakers are a bit more relaxed. Meagen Pollock and I had talks on this final day of the Geological Society of America annual meeting. It felt good to finally give them to audiences made up in large part by our friends and students. I am simply presenting here a few of my slides, including the title image above. The story you may have read in bits and pieces in the Israel entries at this blog. Here is our abstract.

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