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.

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.

Patchiness and ecological structure in a Middle Jurassic equatorial crinoid-brachiopod community (Matmor Formation, Callovian, southern Israel) — An abstract submitted to the Geological Society of America for the 2012 annual meeting

August 6th, 2012

Editor’s note: The Wooster Geologists in Israel this spring wrote abstracts for the Geological Society of America Annual Meeting in Charlotte, North Carolina, this November. The following is from student guest blogger Melissa Torma in the format required for GSA abstracts:

TORMA, Melissa, WILSON, Mark A., Department of Geology, The College of Wooster, Wooster, OH 44691 USA; FELDMAN, Howard R., Division of Paleontology (Invertebrates), American Museum of Natural History, New York, NY 10024

The Matmor Formation is a Middle-Upper Jurassic (Callovian-Oxfordian) marl and limestone unit entirely exposed in Hamakhtesh Hagadol in the Negev of southern Israel. It was deposited in shallow marine waters very close to the paleoequator in the Ethiopian Province of the Tethyan Faunal Realm. It is very fossiliferous throughout most of its 100 meters of thickness. The Matmor Formation has been well described stratigraphically, and several of its fossil groups have been taxonomically assessed (notably the brachiopods, ammonites, crinoids and sclerobionts), but there is yet no community-level analysis of the entire fauna. This work is part of that larger paleoecological project. We systematically collected from the most fossiliferous unit of the Matmor (SU 51 in the local stratigraphy; upper Callovian; Quenstedtoceras (Lamberticeras) lamberti Zone) over several kilometers. The community in this marl is dominated by abundant crinoids (a new species of Apiocrinites), rhynchonellid (Somalirhynchia and Burmirhynchia) and terebratulid (Bihenithyris and Digonella) brachiopods, echinoids (mostly rhabdocidarids), calcisponges and scleractinian corals. Mollusks, other than small attached oysters, are relatively rare, and bryozoans are represented by only a few encrusters. The fossils are concentrated in patches a few tens of meters in diameter separated from each other by featureless, unfossiliferous yellow marl. The patches share many of the same common taxa (especially the crinoids and brachiopods) but differ in the relative abundance of corals. No infauna has been found in this unit, either as trace or body fossils. The environment appears to have been a shallow water embayment with a muddy substrate. Patches of epifauna developed as shelly islands across this seafloor. Crinoids and small corals may have been the pioneers on this soft bottom, providing increasing amounts of skeletal debris to facilitate the settlement of brachiopods and other invertebrates. A periodic influx of fine sediment during storms limited the diversity of this assemblage by smothering patches under several centimeters of mud. This community was thus kept in its early successional stages by periodic disturbance.

Wooster’s Fossils of the Week: A calcareous sponge with a crinoid holdfast (Matmor Formation, Middle Jurassic, Israel)

April 8th, 2012

The Class Calcarea of the Phylum Porifera is a group of sponges characterized by spicular skeletons made of calcium carbonate (calcite in this case). The spicules (small elements of the skeleton) are often fused together, causing the sponges to look a bit like corals or bryozoans. They are among the most common fossils in the Matmor Formation (Middle Jurassic, Callovian) of southern Israel. Melissa Torma and I collected this particular fossil on our expedition last month. It is another indication that the Matmor Formation was deposited in very shallow waters.
This is the underside of the Matmor calcareous sponge. (I wish we had a name for it, but the taxonomy is in considerable flux right now.) You can see the way it grew radially around an encrusting center. In the lower right a circular oyster attachment is visible.
A close view of the top surface of the calcareous sponge showing radiating canals called astrorhizae. They were used to channel water currents for the sponge’s filter-feeding system.
This crinoid holdfast (the base of an attaching stem) locked onto the calcareous sponge after its death. We can tell this because it is bound to the spicular skeleton itself, which was only exposed after the sponge’s soft tissues rotted away. It is not possible to identify the crinoid, but it is likely in the genus Apiocrinites.
The Class Calcarea was named by James Scott Bowerbank in 1864. Bowerbank (1797-1877) was an English naturalist born in London. He helped run a distillery with his brother, making enough money to support his diverse interests in natural history. He collected many fossils in his life, specializing in the London Clay (Eocene). His various publications gained him membership in the Royal Society in 1842. His greatest work was probably a four-volume set titled “A Monograph of the British Spongidae”. (You can read at least part of this work online.) He was well known as a strong supporter of young scientists, opening his home and collections (and use of his valuable microscopes) to all those seriously interested in natural history. I like to think he would have been happy as a liberal arts geology professor!

Last day of 2012 fieldwork in Israel by Wooster Geologists

March 18th, 2012

MITZPE RAMON–Today we finished our exploration of the Upper Cretaceous near Mitzpe Ramon, and then met some old friends for a different project near Ar’arat an-Naqab in the northernmost part of the Negev. This gave me the chance to take a picture of my three favorite Israeli geologists. (Yes, actually getting them to turn around for the camera would have been a bit too much stage management on my part!) On the left is Shlomo Ashkenazi, a retired geological technician and superb field assistant who still volunteers for the Geological Survey of Israel. In the center is Amihai Sneh, also retired from the survey (retirement doesn’t mean much for geologists!) and a mapping genius, and then Yoav Avni, who you met earlier in these posts. At their knees you see a light brown unit that was the subject of our meeting. It is a dolomite, apparently from the Miocene, that has structures in it that may be trace fossils. They wanted my opinion.

Here they are on a bedding plane of the dolomite. Yes, they are trace fossils. My work here is done.

We explored the area around a Bedouin city, one of three in Israel. This is Ar’arat an-Naqab. A “Bedouin city” would have been a contradiction in terms a generation ago. The Bedouin were a nomadic people in this region. The Israeli government set aside land for the settlement of Bedouin, and these modern cities are the result. There is still considerable tension, though, with Bedouin who remain in tents and other structures on what is officially government land. The motivation for them to leave several acres of land they have claimed so that they can live in apartments is, as you can imagine, rather low. We talked to several Bedouin today as we looked for outcrops. Since we were in a government vehicle, there was some suspicion that we were plotting to take their land, but once we explained our geological mission, all was well.

Thus ends the 2012 Wooster Geology expedition to Israel. All our goals were met, and we were once again surprised by how many new things we saw and learned. It has been a wonderful adventure! Thank you again to The College of Wooster and donors and granting agencies who have made such trips possible.

Nabataean water management in the northern Negev (circa 2nd Century BCE)

March 18th, 2012

MITZPE RAMON, ISRAEL–We had an earlier post about water management techniques by Iron Age peoples in the northern Negev. Today during our last period of fieldwork on this trip we ran into a complex Nabataean system in a valley a few kilometers north of Mitzpe Ramon. Nabataeans were an Arab people based in Jordan who spread in influence and settlement through this region from roughly the third century BCE to the third century CE. They are most remembered here for their water systems to support their small villages. The infrastructure they built is still used in many places by the Bedouin.

Today while exploring more Upper Cretaceous sites, we came across the cistern pictured at the top of this entry. It is a Nabataean structure because it is cut into solid rock (the Iron Age equivalents were mostly in clays) and it had a roof held up by the central pillar and interior walls. There are also steps cut into the rock for climbing in and out. The Nabataeans inherited the earlier Iron Age technology and improved on it by better water retention in the container, and reduced evaporative loss.

The cistern we just saw is pictured here from a distance. It is indicated by the tailings of rock debris produced in its construction. On the left hand side you can see a diagonal line of rock indicating part of the water catchment system. There is a similar line on the right, but it is very hard to see.

This even more distant image shows the cistern again as a cone of tailings in the upper left. The valley below is where the irrigated fields were. They are a bit complicated by a series of trenches dug across them recently. (This is an Israeli Army training ground.)

The low rock wall here held in soil for an irrigated field on the left side. The soil has been modified by the original farmers, who built it up with water-holding loess deposits. Some of these fields are still in occasional use by Bedouin who plant wheat in the ancient ground.

Wooster’s Fossil of the Week: A curving scleractinian coral (Middle Jurassic of Israel)

March 18th, 2012

Since Melissa Torma and I recently returned from our expedition to southern Israel (see immediately previous posts), I thought our weekly fossil highlight should be one of our specimens collected from the Middle Jurassic Matmor Formation of Makhtesh Gadol.

This is a colonial scleractinian coral, a group that first appeared in the Triassic. It was originally made of aragonite and is now recrystallized to calcite. The exterior is well preserved, but the interior is coarsely crystalline. You can just make out faint outlines of the individual corallites that make up the colony.

The distinctive feature of this specimen is that it shows different growth directions. Apparently it was disturbed on the seafloor as it grew, so it periodically had to change its direction to keep growing upwards towards the sunlight. It needed the light because it had photosynthetic symbionts in its tissues.

This coral is one of many indications of the shallow paleoenvironment we’ve proposed for the Matmor Formation. It is also encrusted by a variety of sclerobionts, so it is a bit of a community all on its own.

 

Wooster Geologists as guests in a Bedouin village

March 17th, 2012

MITZPE RAMON, ISRAEL–Melissa and I had a fantastic day, much of which will stretch over at least another couple of blog entries. We traveled to the Dead Sea region with our Israeli geologist colleague and friend Yoav Avni and his wife Noa (an education specialist and botanist). We saw extraordinary things at the Dead Sea itself, and then on the way back we visited with some Bedouin friends of the Avnis in a tiny village of three families a few kilometers north of Mitzpe Ramon. In the image above we see the family patriarch Ali, one of his sons, and two visiting neighbor boys. We are gathered around glowing coals in their tent — welcome warmth in the cold. Note that we have just been served sweet Bedouin tea in glasses. (Empty your glass and it is immediately refilled.)  Ali, Yoav and Noa conversed in Hebrew and occasionally translated for us the stories Ali was telling in a very animated way. Melissa and I later commented to each other how interesting it was to watch a conversation we could not understand. So many moving hands!

We were served this Bedouin goat cheese. It is very hard so you nibble off small bits. It is also very salty, so the tea was quite welcome!

This is the inside of the tent. It is made of diverse materials, including cotton sheets and canvas. The rugs are laid on packed soil.

Ali wanted to demonstrate for us the traditional Bedouin way of grinding wheat grains between two carefully-fashioned limestone disks. Here he is adding grain to the hole in the top block.

Ali is rotating the top stone across the surface of the bottom stone with an inserted stick. The limestone must be coarse enough to grind the grain and hard enough not to add rock to your meal!

Here is the product — whole-grain flour! They often mix this with warm water to make a simple porridge.

This is a view of the small village from Ali’s tent. The buildings are made from diverse materials. In the foreground is a donkey pen.

We enjoyed this brief cultural moment very much. The Bedouin are in transition from their original nomadic state to settlement. Ali and his family wish to preserve some of the old ways to educate others (like us) and pass down traditions to succeeding Bedouin generations who will not know life in a tent.

A tribute to our Garmin Montana 600 GPS

March 17th, 2012

MITZPE RAMON, ISRAEL–This isn’t a product review — it’s a love note. We’ve mentioned our field equipment on this blog before, most notably while using iPads in Estonia and Iceland. I just want to express a little gratitude for the technology and national effort that brought the Garmin Montana 600 GPS into my needy hands. (And to thank the Luce Fund at The College of Wooster for buying it!)

You can find many formal reviews of the Garmin Montana online, and some excellent instructive videos on YouTube. As usual with my electronic gear and fancy software, I use less than 10% of their actual capacities. I need a GPS to record sample locations, remember where I parked the vehicle, and figure out how to get from here to there before sunset. The Garmin Montana has made all of this so much easier and intuitive than with my many past GPS devices.

The Garmin Montana is touchscreen-operated, which makes a huge difference when you need quick measurements and want to record waypoints. The screen is also plenty large and in color. I can now record a waypoint and then edit its name (015 becomes “camels be here”, for example). I can also add a long note to each waypoint, all done with a qwerty typepad in landscape mode. So easy. The map and go-to functions are also easily accessed and used. There is a real magnetic compass inside to supplement the one based on the GPS system. There are many other extras, from waypoint averaging (increasing the accuracy of a waypoint) to sunrise/sunset local times, a calculator, alarm clock, stopwatch, calendar … you get the idea. You can even use the device to pace out a polygon and measure its area.

I use a free app called “Garmin BaseCamp” on my MacBook Pro laptop to download and upload waypoints and other data through a USB cable supplied with the GPS. This can include photos for reference in the field. There is also a free software program to connect your device to the Garmin website to receive updates and new free gizmos. (My previous GPS systems did not like the Mac — this one uses the interface quickly and easily.)

Melissa is currently using my old Garmin because of all its stored waypoints from Israel, so we’ve been able to see the two devices in action together. The Garmin Montana receives data from the satellites much faster, and I suspect it is more accurate. My test is to stand at an easily recognized point and take a measurement, then look at it on Google Maps. Above you see a Google Map view of an acacia tree along a wadi in Makhtesh Gadol. I stood beside it and took the measurement shown by the green arrow. At most there is a meter or so difference between where I was standing and what is indicated, so Google Maps has a little correcting to do!

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