Wooster’s Fossil of the Week: A geopetal structure in a boring from the Middle Jurassic of Israel

June 15th, 2014

Geopetal Structure 585We have a very simple trace and body fossil combination this week that provides a stratigraphic and structural geologic tool. Above is a bit of scleractinian coral from the Matmor Formation (Middle Jurassic, Callovian) of Makhtesh Gadol in southern Israel. The coral skeleton was originally made of aragonite. It has been since recrystallized into a coarse sparry calcite, so we can no longer see the internal skeletal details of the coral. In the middle of this polished cross-section is an elliptical hole. This is a boring made by a bivalve (the trace fossil Gastrochaenolites). Inside the boring you see a separate elliptical object: a cross-section of a bivalve shell. This could be the bivalve that made the boring or, more likely, a bivalve that later occupied the boring for a living refuge. This, then, is the trace fossil (Gastrochaenolites) and body fossil (the bivalve shell) juxtaposition.

That stratigraphic and structural interest is that the boring and the bivalve shell are partially filled with a yellow sediment. This sediment has gravitationally settled to the bottom of these cavities (at slightly different levels). These holes have thus acted as natural builders’ levels showing is which way was down and which was up at the time of deposition. We can tell without any clues from the recrystallized coral the “way up” before any later structural deformation (or in this case rolling around on the outcrop) changed the orientation of the coral. Pretty cool and simple, eh? The name for this feature is a geopetal structure. There are some faulted and folded sedimentary rock exposures in the world where we search diligently for these little clues to original orientation (see, for example, Klompmaker et al., 2013). Not all geopetal structures have fossil origins (i.e., Mozhen et al., 2010), but most do. A little gift from paleontology to its sister disciplines.


Klompmaker, A.A., Ortiz, J.D. and Wells, N.A. 2013. How to explain a decapod crustacean diversity hotspot in a mid-Cretaceous coral reef. Palaeogeography, Palaeoclimatology, Palaeoecology 374: 256-273.
Mozhen, G., Chuanjiang, W., Guohui, Y., Xueqiang, S., Guohua, Z. and Xin, W. 2010. Features, origin and geological significance of geopetal structures in Carboniferous volcanic rocks in Niudong Block, Santanghu Basin. Marine Origin Petroleum Geology 3: 15.
Wieczorek, J. 1979. Geopetal structures as indicators of top and bottom. Annales de la Societé géologique de Pologne 49: 215-221.

Wooster Geologist on the Baltic Coast

June 11th, 2014

HotelBalconyView061114SOPOT, POLAND — Yes, that’s a view from my hotel window. I’ve suddenly found myself in an old resort town on the Baltic coast of Poland near the cities of Gdansk and Gydnia. Another one of those astonishing geographic transformations we can so easily make.

I’m here for the Larwood Meeting, an annual gathering of bryozoologists held in various places around the world. Besides learning more about these complex little colonies (both fossil and recent), I’ll be presenting a summary of the work Steph Bosch (’14), Paul Taylor and I did on the new bryozoans from the Middle Jurassic of southern Israel. After the meeting I travel south by train with Tomasz Borszcz to visit Michal Zaton at the University of Silesia for some joint projects. From there it is on to London for a few days with ace paleontologist Paul Taylor at the Natural History Museum. I’m at the end of a research leave this summer so I have more travel than usual.

For now I’m enjoying an extraordinary day on the Baltic shore before the first meeting event this evening. My next images will be much more prosaic! My posts will be a bit shorter than usual because I have to stand in the shower to get enough wireless signal to connect. (There’s an accident waiting to happen …)

Wooster’s Fossil of the Week: A fragment of an asteroid (the sea star kind) from the Upper Cretaceous of Israel

June 8th, 2014

zichor asteroid aboral 585This is not an important fossil — there is not enough preserved to put a name on it beyond Family Goniasteridae Forbes, 1841 (thanks, Dan Blake) — but it was a fun one to find. It also photographs well. This is a ray fragment of an asteroid (from the group commonly known as the sea stars or starfish) I picked up from the top meter of the Zichor Formation (Coniacian, Upper Cretaceous) in southern Israel (Locality C/W-051) on my field trip there in April 2014. We are looking at the aboral (or top) surface; below is the oral view.
zichor asteroid oral surface 585In this oral perspective you can see a group of tiny, jumbled plates running down the center. This is the ambulacrum, which in life had a row of tube feet extending out for locomotion and grasping prey.
asteroid 2004Above is a sea star held by my son Ted on Long Island, The Bahamas, back in 2004. You can see a bit of resemblance between this modern species and the Cretaceous fossil, mainly the  large knobby ossicles running down the periphery of the rays.

The asteroids have a poor fossil record, at least when compared to other echinoderms like crinoids and echinoids. It appears that all post-Paleozoic asteroids derive from a single ancestral group that squeaked through the Permian extinctions (Gale, 2013). There is a significant debate about the evolution of the asteroids (see Blake and Mah, 2014, for the latest). Unfortunately our little critter is not going to help much in its resolution.

Recently it has been discovered that some living asteroids have microlenses in their ossicles to provide a kind of all-surface photoreception ability. Gorzelak et al. (2014) have found evidence that some Cretaceous asteroids had similar photoreceptors. Maybe our fossil goniasterid fragment could yield this kind of secret property with closer examination.


Blake, D.B. and Mah, C.L. 2014. Comments on “The phylogeny of post-Palaeozoic Asteroidea (Neoasteroidea, Echinodermata)” by AS Gale and perspectives on the systematics of the Asteroidea. Zootaxa 3779: 177-194.

Gale, A.S. 2011. The phylogeny of post-Paleozoic Asteroidea (Neoasteroidea, Echinodermata). Special Papers in Palaeontology 38, 112 pp.

Gale, A.S. 2013. Phylogeny of the Asteroidea, p. 3-14. In: Lawrence, J.M. (ed.), Starfish: Biology and Ecology of the Asteroidea. The Johns Hopkins University Press, Baltimore.

Gorzelak, P., Salamon, M.A., Lach, R., Loba, M. and Ferré, B. 2014. Microlens arrays in the complex visual system of Cretaceous echinoderms. Nature Communications 5, Article 3576, doi:10.1038/ncomms4576.

Loriol, P. de. 1908. Note sur quelques stellérides du Santonien d’Abou-Roach. Bulletin de l’Institut égyptien 2: 169-184.

Mah, C.L. and Blake, D.B. 2012. Global diversity and phylogeny of the Asteroidea (Echinodermata). PLOS ONE 7(4), e35644.

Wooster’s Fossil of the Week: My favorite part of a crinoid (Middle Jurassic of Israel)

June 1st, 2014

Apiocrinites negevensis proximale 585In April of this year I completed my 11th trip to southern Israel for fieldwork in the Mesozoic. My heart warmed every time I saw these robust plates of the crinoid Apiocrinities negevensis, which was reviewed in a previous blog post. They are thick disks of calcite with a heft and symmetry like exotic coins. They are easy to spot in the field because of their size and incised perfect star. They have been a critical part of our paleoecological and systematic studies of the Matmor Formation (Callovian, Middle Jurassic) in the Negev. Lizzie Reinthal (14) and Steph Bosch (14) know them particularly well!
negevensis proximales 1This part of the crinoid is called the proximale. It has a round base that articulates with the columnal below it in the stem, and its top has five facets that hold the basal plates of the calyx. It is thus the topmost columnal, specialized to serve as the integration between the articulated stem below and the complicated head above. The pentastellate (five-armed star, but you probably figured that out) impression is called the areola. In the very center is the open hole of the lumen, which goes from the head all the way down through the stem to the holdfast as an internal fluid-filled cavity.
Composite Miller Apiocrinites arrowedAbove are Miller’s (1821) original illustrations of Apiocrinites rotundus with the proximale shown by the red arrow. Note how thin this piece is compared to the equivalent from Apiocrinites negevensis. The significant thickness of the proximale is one of the distinguishing features of the Negev species.

I saw many more of these beautiful fossils in the field this year. We don’t need any more for our research, but they always indicate that other good fossils are nearby.


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

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.

Wooster’s Fossil of the Week: One sick crinoid from the Middle Jurassic of Israel

May 11th, 2014

IsocrinidAMy first thought on seeing this distorted fossil was how much it evoked one of those Palaeolithic “Venus figurines“. It is certainly difficult to deduce that this is actually a crinoid column (or stem). It was found during my last expedition to the Middle Jurassic Matmor Formation in Makhtesh Gadol, southern Israel (location C/W-506). This particular crinoid was infected by parasites that caused the grotesque swellings of the skeletal calcite in the individual columnals (button-like sections of the column). The infection of a species of Apiocrinites in the Matmor is the subject of a paper now in press by me, Lizzie Reinthal (’14) and the pride of Ohio State University, Dr. Bill Ausich. That story will be a later Fossil of the Week entry. The specimen above, though, is different. To my surprise, it is a parasitic infection in an entirely different crinoid order.

IsocrinidBHere’s another view of the crinoid column. The top third shows some of the original star-shaped columnals in side view. This tells us that the crinoid was an isocrinid, possibly the cosmopolitan Isocrinus nicoleti. This group contains the famous and somewhat creepy crawling crinoids. We have just a handful of isocrinid stem fragments in the Matmor despite a decade of searching for a distinctive calyx (the head of the little beast). Note that the gall-like swellings have holes in them. This will be important in a later analysis of the parasitic system here.

IsocrinidCAnd now the other side of the fossil. Again, in the top part you can make out star-shaped columnals, but that distinctive outline is lost in the swollen column below. The stem must have been seriously hindered from flexing and bending with such a debilitating infection.


Salamon, M.A. 2008. The Callovian (Middle Jurassic) crinoids from northern Lithuania. Paläontologische Zeitschrift 82: 269-278.

Tang, C.M., Bottjer, D.J. and Simms, M.J. 2000. Stalked crinoids from a Jurassic tidal deposit in western North America. Lethaia 33: 46-54.

Wilson, M.A., Reinthal, E.A. and Ausich, W.I. 2014. Parasitism of a new apiocrinitid crinoid species from the Middle Jurassic (Callovian) of southern Israel. Journal of Paleontology (in press).

Last work of Team Israel, Matmor Division

May 5th, 2014

Team Israel 050514WOOSTER, OHIO–Steph Bosch (’14) and Lizzie Reinthal (’14) volunteered to examine the Matmor Formation fossils I collected last month in Israel. Each fossil, most of which are crinoid ossicles, must be scanned under a microscope for tiny encrusters (especially bryozoans), borings, and bite marks. In the image above you can see the collection bags on the left and our three ‘scopes arranged so that we can exchange interesting bits that we find. I had planned to do this work all by my lonesome, and it would have taken a full day. With Steph and Lizzie, though, we were done in an hour and a half. No wonder — they’ve spent the last year doing this kind of analysis!

Israel specimens 050514And here are the results. Each paper tray has a particular category of fossil from a specific location. We found many little (and I mean little) treasures that my future students and I can now study. I’m grateful for the expert help.

Team Israel 2013 will be graduated a week from today. Congratulations to them!

Wooster’s Fossil of the Week: A helpful echinoid from the Upper Cretaceous of Israel

April 27th, 2014

Echinoids a 042214These beaten-up fossils have served me well in the field this month. They are the regular echinoid Heterodiadema lybicum (Agassiz & Desor, 1846). They are common in the Cenomanian throughout northern Africa and the Middle East. These particular specimens, the other sides of which are shown below, are from the En Yorqe’am Formation we’ve been studying here on the rim of Makhtesh Ramon, southern Israel. When I find them in abundance I know I’m in the top half of that formation. They’ve previously been featured indirectly as a Fossil of the Week for the bites they made into the shells of oysters, producing the trace fossil Gnathichnus.
Echinoids b 042214The species Heterodiadema lybicum was named by Pierre Jean Édouard Desor (1811-1882) in 1846. We’ll meet him in a later entry. The genus Heterodiadema was erected in 1862 by Gustave Honoré Cotteau (1818-1894), who is pictured below. There is not much at all about Cotteau in the English literature, but with Google Translate I was able to sort out a bit of his story from the French. He was one of those glorious amateurs who make such important contributions to the science of paleontology. (I like the new term “citizen scientists” for this group, although I emphasize I’m a citizen too!) Cotteau was a judge in Auxerre, Burgundy, France. In his spare time he had a passion for living and fossil echinoids, eventually amassing a collection of over 500 species. He was also, as you might guess, a volunteer curator of the city museum in Auxerre. In 1889 he was President of the Société zoologique de France, a highly prestigious position. He was an important force in the early understanding of echinoderms.
Cotteau GustaveAgain, these specimen photos were taken under “field conditions” in Israel with a cleaner’s cloth for a background. As you read this, though, I am with luck back in my cozy home in Wooster.


Agassiz, L. and Desor, P.J.E. 1846. Catalogue raisonné des familles, des genres, et des espèces de la classe des échinodermes. Annales des Sciences Naturelles, Troisième Série, Zoologie 6: 305-374.

Geys, J.F. 1980. Heterodiadema libycum (Agassiz & Desor, 1846), a hemicidaroid echinoid from the Campanian of Belgium.  Anales de la Societe geologique du Nord 99: 449-451.

Smith, A.B., Simmons, M.D. and Racey, A. 1990. Cenomanian echinoids, larger foraminifera and calcareous algae from the Natih Formation, central Oman Mountains. Cretaceous Research 11: 29-69.

Among citizen scientists in southern Israel

April 24th, 2014

Zichor M2 M3 042414MITZPE RAMON, ISRAEL–Today Yoav Avni and I drove south to meet an enthusiastic group of naturalists in Arava of the Jordan Rift Valley. The group is led by Dr. Hanan Ginat and consisted of a micropaleontologist and three amateur collectors who have all added considerably to scientific knowledge. We did fieldwork together in the magnificent Menuha Formation (Upper Cretaceous). The outcrop above is the boundary between a middle unit of the Menuha (“M-2″) and the upper chalks (“M-3″) in Wadi Zichor.

Gidon and fossils 042414Here is Gidon and a fraction of his collection, which is mostly from the local Cretaceous. There were fossil types here I’ve never seen before. Like all good citizen scientists, he knows how to collect and observe with location and stratigraphic control, and he has learned an immense amount about fossils and the organisms they represent.

Winny home 042414We had tea in Winny’s desert house. The interior (and exterior) is dominated by delightful fossils (and many other objects). It is a classic desert-dweller’s home. The micropaleontologist Sarit is in the foreground. (I have only phonetic first names. I’ll collect last names later!)

Stratodus Winny 042414Winny collected this four-meter long Cretaceous fish named Stratodus. She must now be the world’s expert on its complex anatomy. It is just a taste of her other fossils, including a bryozoan-encrusted ammonite from the Ora Formation (Turonian) she freely and eagerly gave me for research.

Field party 042414The field party is here assembled to study a site where they helped find and excavate an Elasmosaurus plesiosaur — the first in Israel.

Menuha view 042414A view of the Menuha Formation in the Arava. This is an extraordinary outcrop, and you can tell by the minimal vegetation that this is the driest part of the Negev.

I very much enjoyed my time with this fun and dedicated crew. They reminded me so much of the naturalists I grew up with in my own desert home of Barstow, California. I made many connections here that will benefit future research programs and Independent Study projects for Wooster students. It was inspiring to see what joy these people have in pursuing their scientific passions, like all other citizen scientists I work with.

This was my last day of fieldwork on this expedition. Tomorrow the long trip home begins!

Wooster Geologist in Jerusalem and the Judean Mountains

April 23rd, 2014

GSI buildings 042314MITZPE RAMON, ISRAEL–Very early this morning (5:05 am) Yoav and I boarded a bus in Mitzpe Ramon for a journey north to Jerusalem. After a change of buses in Beersheva, we arrived in Jerusalem 3.5 hours later. (This is Yoav’s commute to his office!) I was scheduled to give a morning talk at the Geological Survey of Israel‘s headquarters in a crowded haredi (ultraorthodox)  neighborhood. It is always a moment to leave the noisy streets and pass through a gate onto the campus of the Survey, shown above. This is an old British military base from the 1940s, and it shows the wear.

GSI parking 042314The parking here is incredible. The cars are closely imbricated. Drivers who blocked other cars leave their phone numbers on their windshields so they can be summoned to move. Some just leave their keys inside for others to shift them out of the way. Here’s an advantage of taking the bus! The Survey will have a new campus elsewhere in the city in about four years.

Talk chairs 042314Geologist and good friend Amihai Sneh is here setting up chairs for the talk in the conference/tearoom.

Talk set up 042314Here’s my lecture set-up ready to go. The talk went well enough, and my geological colleagues had a lot of good comments and ideas afterwards. As with any presentation, I was most pleased to have it over!

Yoav IS 042314After the talk and lunch, Yoav, Amihai and Eitan Sass (a well-known Israeli geologist and former advisor of Yoav) planned a fieldtrip to further explore Cenomanian units in an attempt to solve some correlation dilemmas. This is the same project we have been working on with the En Yorqe’am Formation to the south. We actually used Yoav’s equivalent of an Independent Study thesis he completed over 25 years ago in Jerusalem. It looks like a master’s thesis. A critical fence diagram from the work is shown above. It was very useful in our explorations.

Yoav Bet Meir Newe DanielYoav is here examining an exposure of the Bet Meir Formation in the Newe Daniel settlement in the southern West Bank. We examined it in several places, noting changes in the amount of dolomitization and fossil content. It was best exposed here because of recent construction.

Nodules Bet MeirDr. Sass has studied these nodules in the Bet Meir Formation and concluded they are after anhydrite nodules. In fact, some still have anhydrite entombed within later quartz replacement. This chalky sediment was likely influenced by flows of dense brines from nearby shallow evaporitic basins.

Newe Daniel 042314Did I mention we were in the West Bank? This was very interesting, and an unexpected visit for me. These settlements are entirely normal once you’re on the inside, but the various layers of security measures on the outside are impressive. I learned a lot about the history of this particular place from my colleagues. Complex, to say the least.

Herodium 042314History moment. From a tower in Newe Daniel you can see a curious conical mountain called the Herodium. It is far too steep to be natural. It was constructed by Herod the Great as a palace and his tomb. The recent discovery of the actual burial site is a dramatic story.

Jerusalem surrender monumentBonus history moment: On the walk from the bus station to the Survey headquarters, Yoav and I passed this monument to the surrender of Jerusalem to British troops on December 9, 1917. This too is a good story. It happened on this spot. Check out the famous image below from that day.



Where sedimentology meets structural geology

April 21st, 2014

A seismite? 042114MITZPE RAMON, ISRAEL–“Like a hot dog in a bun.” Late this afternoon, while exploring the Eocene (Lutetian) Horsha Formation near the Nabatean/Roman/Byzantine city of Avdat, Yoav Avni and I ran across these odd features in a limestone layer within the chalks (near N 30.79119°, E 34.75494°). They consist of an elongate core of coarse, bioclastic sediment (the hot dog) in chalky sediments folded around them (the bun). They are all oriented in the same direction.

Another seismite type 042114Some are as big as canoes; others like gravy boats. We suspect that these are seismites — sedimentary sturctures formed by seismic shaking. The chalky, water-saturated sediment would have responded plastically as the slightly denser bioclastic sediments above collected in troughs and then began to descend down into the chalk. This is just an idea. If someone else has seen structures like these, please let us know!

Byzantine Cistern 042114Just below these funny structures is this nice Byzantine cistern filled with water. It is on the edge of a wadi, with about a half-meter step above the wadi base. It has this narrow doorway that leads into an interior cavern, all hand-carved. During a flood, the water reaches a level in the wadi where it begins to decant into the cistern, reducing the amount of sediment that would otherwise fill the cavity quickly. A couple of years ago Yoav organized a team to excavate centuries of silt from this cistern. Now it is full from the winter rains, providing a water hole for the local Bedouin children. It also shows that the Byzantine water storage and conservation techniques of 1500 years ago still work fine today.

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