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A Wooster Geologist in Tanzania

October 10th, 2015

IMG_0162Oscar Mmari (’14) is a Wooster Geology alumnus who did field work in Israel as part of his Independent Study. After his graduation he has had excellent geological experience in Africa and Europe, most involving mining and other resource-related industries. He has kindly given us this account of a field trip he took on August 4, 2015, near Dar es Salaam, Tanzania.

Appreciating the Rocks

By Guest Poster Oscar Joseph Mmari (’14)

A Dar es Salaam traffic jam, like those in most African cities, is a memorable experience for anyone who has braved the streets of the commercial capital. The narrow roads are constantly chocked with sluggishly moving cars and fumes suffocating the air. This can be inconvenient and people have missed flights let alone been tardy to momentous meetings. It is a far cry from the orderly multiple-lane highways spanning through Ohio. Equipped with this knowledge, our trip to four different outcrops spanning two regions all in one day had to be immaculately planned.

Geology field trips are vital to the growth of every geoscientist. The trips, apart from allowing geologists visit exotic places on earth, reinforce fundamental field skills important to the discipline. In addition, it underscores the scale difference between outcrops in the field and seismic wiggles in Petrel. This is why when my supervisor was in town, I organized a field trip. The overarching theme of the trip was to observe different sedimentary successions in the Coastal area around Dar es Salaam.  Additionally, one of the outcrops provided an analogue to Songo Songo gas field.  Geological outcrop analogues serve a great purpose in understanding new fields because of their capability of providing information at a scale and lateral that cannot be determined from seismic and well data in the subsurface. Songo Songo gas field is a Lower Cretaceous reservoir aged Neocomian to Albian sandstone reservoir producing 80 MMscf/day for gas plants in the United Republic of Tanzania.

The trip started early at 7:30 am and the first stop was just a few yards from the office in Dar es Salaam. Oyster Bay plays home to host of different marine organisms that congregate in and around an extensive coral environment.

IMG_0075Corals provide shelter and food for many organisms and can support enormous ecosystems. As the sea level changed, the effects of waves and tides on these rocks can be seen especially in the neatly exposed corals on the beach. Being geologists, we spent some time looking at fossils and the sedimentary fabrics pondering about the effects of deposition and erosion in the area.

The second stop was a little further from the office. The Pugu Hills are located about 15 miles south-west of the BG Tanzania office but the outcrops we were trying to find were elusive.  After asking several locals, making a few phone calls to colleagues and gingerly passing along overgrown ancient roads, where the GPS was not very helpful, we reached the former kaolinite quarries in Pugu. The Pugu Hills form one of the highest points in the region due to uplifts within the last 5 million years. The sediments in the quarry are amalgamated fluvial sandstones with gravel lags, which are cut by a number of NNE trending faults and joints. The intensely weathered sandstone-clay sequence is now dominated by the clay mineral kaolinite which provided raw material for the now dilapidated factory and was extracted for pottery manufacture.  It also contains refractory minerals such as quartz and zircon which are resistant to alteration.


IMG_0087The next stop, after an excellent lunch, was at Msolwa area were we looked at Lower Cretaceous fluvial and estuarine sand deposits, which are of similar age as the gas-bearing sands of Songo Songo. We spent some time discussing the direction of flow and the possible depositional environment. The last stop was in the Wami River valley where we observed metamorphic rocks uplifted to the surface and an impeccable sedimentary-metamorphic contact.



IMG_0136On our way back we saw several signs of the on-going hydrocarbon exploration in on shore Tanzania, which was an optimistic sign in the current oil price climate. When we got back to the city, it was dark, we were tired, but it had been a day well spent. The traffic was jammed solid and there was no clever planning that would get us out of this one. Well, at least we had to some rock stories to discuss.

Wooster’s Fossils of the Week: A rugose coral and its encrusters from the Middle Devonian of New York

October 9th, 2015

Heliophyllum halli Bethany Center Centerfield 2 585This week’s fossils were found on a most excellent field trip to the Niagara region of New York in August. One of our outcrops was a small patch of gravel in Bethany Center where the Centerfield Limestone Member of the Ludlowville Formation (Givetian, Middle Devonian) was exposed. My colleagues and I found many interesting fossils here. The largest specimen I collected was the above rugose coral.
1 Heliophyllum halli Bethany Center Centerfield 2 copyIt is Heliophyllum halli Milne-Edwards and Haime, 1850. This species is very common throughout the Devonian Hamilton Group of New York, Ontario and surrounding areas. The 90-degree bend in the specimen is a result of the living coral being knocked over onto its side and then twisting to grow upwards again.
3 Rugose Bethany Center Centerfield 3These corals are called “rugose” because of their “wrinkled” exteriors, easily seen in this view. The solitary forms, like this one, are a single corallite that held one polyp in life. Their conical growth form gives them another nickname: “horn corals”. Rugose corals also come in colonial varieties, which we’ve covered before in this blog. Their skeletons are made of thick calcite, so they are almost always well preserved. These corals are distinguished from others by their strong internal vertical walls (septa) and relatively few horizontal or angled partitions (tabulae and dissepiments). They lived like most other corals as sessile benthic (stationary on the bottom) predators catching food with their tentacles. It is still uncertain whether they had photosynthetic symbionts (zooxanthellae) like modern corals. Emily Damstra has a nice reconstruction of living Heliophyllum halli.
4 Encrusting Bryozoan Bethany CenterThis particular coral has a collection of encrusting organisms on its exterior. Above is a remnant of a bryozoan.
5 Microconchid Bethany CenterThe encrusting coiled shell in the lower left is a nice microconchid (a mysterious lophophorate) and at the top is another type of bryozoan. Many of these encrusters are found on eroded parts of the coral skeleton, so they likely encrusted it after death.

Heliophyllum halli was named by Milne-Edwards and Haime in 1850. We’ve introduced Henri Milne-Edwards (1800-1885) before, and even James Hall (1811–1898) for whom the species is named. Jules Haime (1824-1856) is less known. He died too young at age 32, which may explain why we have no images of him. HIs father was a prominent physician, Auguste Haime (1790-1877). Jules, like many 19th Century paleontologists, started in medicine (studying in Tours) but gravitated toward the excitement in natural history, becoming a zoologist and paleontologist. He specialized in corals, joining up early in his career with Milne-Edwards. Haime rose fast in his new profession. One year before his death he became a professor of natural history at the Lycée Napoléon in Paris. In 1856 he was appointed vice-president of the Société géologique de France, but died a few months later.


Baird, G.C. and Brett, C.E. 1983. Regional variation and paleontology of two coral beds in the Middle Devonian Hamilton Group of Western New York. Journal of Paleontology 57: 417-446.

Brett, C.E. and Baird, G.C. 1994. Depositional sequences, cycles, and foreland basin dynamics in the late Middle Devonian (Givetian) of the Genesee Valley and western Finger Lakes region. In: Brett, C.E., and Scatterday, J., eds., Field trip guidebook: New York State Geological Association Guidebook, no. 66, 66th Annual Meeting, Rochester, NY, p. 505-585.

Milne-Edwards, H. and Haime, J. 1850-1854. A monograph of the British fossil corals. London, Palaeontographical Society. 736 pages.

From Rittman to Apple Creek

October 6th, 2015


Geomorphology (Geology 300) has been taking advantage of the good weather this Fall traveling in the area. Above the full class stands on a point bar of the Apple Creek. Waves go out to Brian Merritt who experienced an injury earlier in the semester, we wish his a speedy recovery and sure could use his expertise in hydrology, carrying heavy equipment and doing much of the work (see below).

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Brian augers a hole in the Kame at Browns Lake, in the background is a 350 year old white oak and we hypothesize that this area may contain old soils that have never seen the plow.

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Surveying in the discharge transects and well locations.


The gaging team sets up another transect.


Taking notes – greatly appreciated when we return to the lab and try to make sense of what we measured.


The shallow wells were measured for relative water levels and water temperature.


A surprise the team discovered – Roy takes a sample from the upper unit as Julia takes careful notes. The hypothesis is that this layer, which lies uncomformably on top of fluvial gravels, is in the class of legacy sediments, eroded soils and windblown dust empounded at the site when a mill was operating in the valley.


Possible Mill or dam site?


Much of the class at Zollingers Pit in Rittman – Krysden and Andrew are not present as they were excavating sediment for their project.


The group at Browns Lake.


Discussing why we install a shallow and deep well side by side.


Returning to the vans after work in Wooster Memorial Park (aka Spangler).


A bald eagle circled overhead at the Apple Creek site.


Wooster’s Fossil of the Week: A spherical bryozoan from the Upper Ordovician of northeastern Estonia

October 2nd, 2015

1 Esthoniopora Kukruse 585Way back in July 2007 we had our first Team Estonia doing geological field research. Andrew Milligan (’08) and I, with our friend Dr. Olev Vinn of the University of Tartu, explored the Upper Ordovician of the northeastern part of the country, perilously close to the Russian border. Most of our work was stratigraphic and related to echinoderms, but I picked up several of these beautiful spherical bryozoans. This specimen comes from the Kiviõli Member, Viivikonna Formation, Kukruse Stage, Upper Ordovician, of Kohtla-Nõmme Quarry (N 59.35665º E 27.22343º). You won’t find the quarry on a map, though, because it was soon afterwards erased by continual mining. Now it is a grassy field. Since we are studying bryozoans this week in my Invertebrate Paleontology course, I’m bringing these specimens to the blog.

2 Esthoniopora subsphaericaThis is what two specimens of this bryozoan look like before cutting. They have the size and shape of golf balls.

3 Esthoniopora subsphaericaHere are the same two specimens cut in half and polished to show the growth rings and tubular zooecia (which held the feeding zooids of the living bryozoan).

4 Esthoniopora subsphaericaIn this closer view you can see the polygonal outlines of the zooecia, now filled with calcite. In the lower right is a boring that cut through the skeleton soon after the bryozoan’s death on the Ordovician seafloor. It has a bit of sediment that filled the boring except for the very center, which apparently held the body of the borer.

This bryozoan is the trepostome Esthoniopora subsphaerica (Bassler, 1911). Bassler originally called it Hemiphragma subsphaericum, which is a nod to its abundant hemiphragms (curving partitions in the zooecial tubes). As bryozoans go, this one has a fairly simple structure with no exozone, endozone, monticules or spines. How it lived on the seafloor with such a spherical shape is a bit of a mystery. A slightly flattened patch is probably where the sphere contacted the sediment. The borings in these bryozoans were studied by Wyse Jackson and Key (2007).

5 Ray BasslerThe species author, Raymond S. Bassler (1878-1961), was an American paleontologist prominent in the study of bryozoans and other encrusting organisms. He was born in Philadelphia and became very interested in fossils from childhood. He received his bachelor’s degree from that paleontological bastion the University of Cincinnati in 1902, followed quickly by his master’s (1903) and PhD (1905) degrees from George Washington University, where he served as a professor for over forty years. He also began work at the United States National Museum in Washington in 1910, rising through the ranks to become Head Curator in 1929. His main interests were bryozoans from the Cenozoic of the Gulf and Atlantic coasts, on which he had long collaborations with the French bryozoologist Ferdinand Canu. He also worked closely with Charles Schuchert, Carl Ludwig Rominger, and Edward Oscar Ulrich. Ray Bassler died in 1961.


Bassler, R.S. 1911. The Early Paleozoic Bryozoa of the Baltic Provinces. Bulletin of the US National Museum 77: 1-382.

Koromyslova, A.V., Fedorov, P.V. and Ershova, V.B. 2009. New records of bryozoans from the Lower Ordovician of the Leningrad Region and intercolonial variability in Esthoniopora lessnikowae (Modzalevskaya). Paleontological Journal 43:39–45.

Wyse Jackson, P.N. and Key, M.M. 2007. Borings in trepostome bryozoans from the Ordovician of Estonia: two ichnogenera produced by a single maker, a case of host morphology control. Lethaia 40: 237-252.

Wooster’s Fossil of the Week: “Lapis Judaicus” from the Middle Jurassic of southern Israel

September 25th, 2015

Pseudocidaris spine 371Paul Taylor (Natural History Museum, London) is, along with his other talents, an expert on the folklore of fossils. His accounts of how fossils have been used and imagined in the past are fascinating, especially to paleontologists who work with them every day. (We had an example this summer at Whitby, England, with Saint Hilda and the ammonites.) So I was primed when Tim Palmer told me about an article on “Lapis Judaicus” or “Jews’ Stone” by Christopher Duffin (2006). Tim thought the medicinal value of these things was particularly appropriate for me.

At the top of this post is a clavate (club-shaped) spine from the echinoid Pseudocidaris. I collected it years ago from the Matmor Formation (Middle Jurassic, Callovian) exposed in Makhtesh Gadol, southern Israel. In classical and medieval times this would have been a Jews’ stone (or jewstone). Its shape is critical, of course, but also its provenance in the Middle East.
Gesner 1565 figureThis is an illustration from Gesner (1565) showing a set of Jews’ stones (taken from Duffin, 2006, fig. 2). The image on the right (“.3”) is very close to our Pseudocidaris spine. The range of shapes for Jews’ stones was broad; all simply had to have this general clavate appearance and be from the Holy Lands.

Jews’ stones are examples of a kind of sympathetic magic attached to natural objects. It was thought that the globular shape of these spines resembled a bladder, and so these stones could be used to treat urinary disorders of various kinds. Sometimes the ancient prescriptions called for them to be sucked, but more often the stones were ground into a powder and combined with other exotic ingredients for consumption either orally … or other ways. The Jews’ stones were thought to have both preventative value as well as curative.

And that is why Tim recommended them to me. One of their primary uses was for the cursed kidney stones.

Nice to know I could have a potential treatment available right there on the outcrop!


Duffin, C.J. 2006. Lapis Judaicus or the Jews’ stone: the folklore of fossil echinoid spines. Proceedings of the Geologists’ Association 117: 265-275.

Gesner, C. 1565. De Rerum Fossilium. Lapidum et Gemmarum maxime, figures et similitudinibus Libel’: non solum Medicis, sed omnibus rerum Naturae ac Philologiae studiosis, utilis et jucundus futurus. Publisher unknown, Zürich.

Gould, S.J. 2000. The Jew and the Jew Stone. Natural History 6: 26-39.

Team Yorkshire gets all geochemical

September 20th, 2015

1 MMlab091915BRYN MAWR, PENNSYLVANIA–When we last saw Mae Kemsley (’16) and Meredith Mann (’16) in this blog, they were celebrating the end of their Senior Independent Study summer fieldwork on the coast of North Yorkshire, England. This weekend the three of us traveled to Bryn Mawr College and the geochemistry lab of Professor Pedro Marenco to start the geochemical analysis phase of our research. We learned a lot under Pedro’s kind and generous direction.

2 CW715 090315 belemnitesBoth Mae and Meredith have belemnite fossils in their field collections. Meredith has just a few from the Passage Beds Member of the Coralline Oolite Formation (Upper Jurassic, Oxfordian); Mae has dozens from the Speeton Clay (Lower Cretaceous). A belemnite was a marine squid-like cephalopod that had a hard, bullet-shaped internal structure called a guard (shown above). These guards are made of almost pure calcite which took in trace elements from the seawater as they grew. The carbon and oxygen isotopes in their calcite crystals also reflect the isotopic composition of the seawater. These fossils are thus geochemical repositories from ancient seas. We are interested in what our belemnites tell us about the ambient chemical conditions in their environments, which in turn are proxies we can use to interpret paleotemperatures and other factors.

3 Belemnite cut sampleIn our Wooster geology labs we cut small disks from a series of belemnites, then polished the surfaces and cleaned them thoroughly. We brought these prepared disks to Pedro’s lab in Bryn Mawr.

4 Drilling 091915Mae is here in the Bryn Mawr petrography lab using a small drill to excavate fine calcite powder from the belemnite disks. This powder, measured in fractions of a gram, was then collected into sheets of weighing paper, folded like origami and taped to keep it in place.

5 Weighing091915Mae and Meredith are here weighing the powder samples with Pedro’s fancy balances. Each plastic sample vial had to be paced through an ion generator to reduce static charge and improve measurements to the microgram. A lot of chemwipes, weighing sheets, and gloves are used in the process to reduce contamination.

6 Mae tubes 091915After dissolving the powder samples in acid, and then diluting the liquids in carefully-measured ways, we finally ended up with these precious tubes filled with essence de belemnite. We learned how much work goes into preparation of geochemistry samples — a lot!

7 ICP MS 0091915The liquid samples are now ready for analysis in a device called an ICP-MS, which stands for Inductively Coupled Plasma Mass Spectrometer. This is the process and equipment Wooster geologists Mary Reinthal (’16) and Chloe Wallace (’17) described in their recent geochemistry blogpost. We’re doing the same thing: assessing the trace elements in our samples. Pedro will later run our samples through this magic machine and give us the results. We have a duplicate set of drilled belemnite powders to send to another lab for carbon and oxygen isotope analysis.

8 Katherine Pedro 091915Thank you very much to our Bryn Mawr hosts Dr. Katherine Nicholson Marenco (’03) and Dr. Pedro Marenco. We are very much looking forward to our continuing collaboration. Thanks as well to Dr. Paul Taylor of the Natural History Museum in London who was our Essential Companion in the field.

Wooster’s Fossils of the Week: calcareous sponges from the Middle Jurassic of southern Israel

September 18th, 2015

1 Four Matmor SpongesThis post is in honor of Yael Leshno, a graduate student at The Hebrew University of Jerusalem who is beginning her dissertation on the Middle Jurassic marine fossils of Israel. I’m proud to be on her committee. She will have some fascinating material to work with, and she has great ideas to test. This will be a fun and productive project.

Among the Jurassic groups Yael will concentrate on are the calcareous sponges. This is ambitious because they are poorly known and the literature is replete with outdated names and concepts. Her work will be of great value, though, because sponges can tell us a lot about the environments in which they flourished. They may also give us much needed information on the biogeographical context of the Jurassic faunas of the Middle East.

Above are four sponges from the Matmor Formation (Callovian, Middle Jurassic) of Makhtesh Gadol, southern Israel. These types of sponge are fun because they actually look like sponges with their porous exteriors and central osculum (excurrent hole). They are the least complicated type of fossil sponge. (Yael will see plenty of the challenging ones!)
2 Matmor calcisponge Peronidella 585In this closer view of one of the Matmor sponges you can see the complex spicular network of the exterior (the structure that held the living cells). You will also note near the base the coiled tube of a sabellid worm named Glomerula gordialis (Schlotheim, 1820).
3 Matmor Peronidella osculum 585Here is a top view looking into the osculum of the largest specimen. Sponges are filter-feeders, sucking in water through their exterior pores, filtering the organic material out, and then sending the used water out an osculum like this.

This sponge type is traditionally named Peronidella Hinde, 1893; it would be then placed within the Family Peronidellidae WU, 1991. I’m suspicious of this name because it used for sponges from the Devonian through the Cretaceous, so it is likely a form-genus (meaning a named form that may not have particular systematic value). Yael will no doubt section these common Matmor sponges and find enough internal detail to come up with a more useful name.
4 GJ Hinde imageGeorge Jennings Hinde (1839-1918; image from Woodward, 1918) named the fossil sponge genus Peronidella in 1893. Hinde grew up in a farming family in Norwich, England. He was clearly a self-starter, studying classical languages and science on his own as a boy. When he was about 16 he listened to a lecture given by a clergyman on the Scottish geological polymath Hugh Miller (1802-1856), who had recently died tragically. Hinde was intrigued and began to explore geology. In 1862, after beginning his own farming, Hinde visited the geological collection at the British Museum in London. He began an acquaintance there with a family relative, the famous geologist and paleontologist Henry Woodward (1832-1921). In that same year Hinde sold his farm and moved to Argentina to raise sheep. A few years later he traveled to North America and began an epic seven years studying geology, traveling across the eastern half of the continent. (He must have had a considerable source of income for this!) He enrolled as a student in Toronto University under the paleontologist H.A. Nicholson (1844–1899) and began to produce his first geological papers. When he returned to England in 1874 he was elected a Fellow of the Geological Society of London. He continued to travel, this time over much of Europe and the Middle East. In 1880 he finished his PhD under Professor Karl Alfred Ritter von Zittel (1839-1904). He had a long career after that with numerous papers and scientific awards. Long et al. (2003) adds to this biography that Hinde very much wanted women to be allowed membership in the Geological Society of London, a point neglected in the obituary by Henry Woodward (1918). Hinde did not, alas, live to see the success of his progressive quest. The first woman was elected a Fellow of the GSL on May 21, 1919, a little more than a year after his death.


Hinde, G.J. 1893. A monograph of the British fossil sponges, Part III. Sponges of the Jurassic strata, p. 189-254. The Palaeontographical Society, London.

Hurcewicz, H. 1975. Calcispongea from the Jurassic of Poland. Acta Palaeontologica Polonica 20: 223-291.

Long, S.L., Taylor, P.D., Baker, S. and Cooper, J. 2003. Some early collectors and collections of fossil sponges represented in The Natural History Museum, London. The Geological Curator 7: 353-362.

Vinn, O. and Wilson, M.A. 2010. Sabellid-dominated shallow water calcareous polychaete tubeworm association from the equatorial Tethys Ocean (Matmor Formation, Middle Jurassic, Israel). Neues Jahrbuch für Geologie und Paläontologie 258: 31-38.

Woodward, H. 1918. Obituary: George Jennings Hinde, Ph.D.(Munich), FRS, FGS, VP Pal. Soc. Geological Magazine (Decade VI) 5: 233-240.

Zittel, K.A. 1879. Studien über fossile Spongien, Teil 3. — Bayer. Akad. d. Wiss., math. naturwiss Cl. Abb. 13: 91-138.

ICP-MS OSU Adventure

September 14th, 2015

[Guest bloggers: Mary Reinthal and Chloe Wallace]

In five days, three Wooster geologists prepped and analyzed over 50 samples, ate tons of food, and learned a lot of science. Okay, maybe not tons of food, but we did eat a lot. For three solid days, rising junior Chloe Wallace and rising senior Mary Reinthal were able to dabble in wet chemistry at the Ohio State University under the guidance and supervision of Dr. Pollock. The days were spent in geochemistry labs preparing sieved whole rock samples for ICP-MS analyses.

For those not familiar, ICP-MS stands for Inductively Coupled Plasma-Mass Spectrometer. ICP-MS is a system that allowed us to determine trace elements in our samples, which better help us separate lithofacies units into distinctive geochemical groups. This, then, allows for a broader understanding of how and when these units were emplaced in relationship to one another. That’s a lot of information from some geochemistry.

Chloe and Mary in the clean lab.

Chloe and Mary in the clean lab.

One of the days, Chloe and Mary were able to get outside and venture around campus and check out some of the sights. But most days at OSU main campus were spent not in the sun, but in the basement, measuring solutions, precisely weighing powders, wearing clean-lab gear, or inputting data into the computer.

Chloe weighing whole-rock powders.

Chloe weighing whole-rock powders.

Mary pipetting acids into the vials to digest the samples.

Mary pipetting acids into the vials to digest the samples.

After long days of work, however, we got to peruse the campus scene, and we ate somewhere new every day. It was exhausting work, but the hope is for some good data.

Mary and Chloe celebrating the completion of sample preparation!

Mary and Chloe celebrating the completion of sample preparation!

Wooster’s Fossil of the Week: A starry bryozoan from the Upper Ordovician of southern Ohio

September 11th, 2015

Constellaria polystomella Liberty Formation 585At this time of the year I pick out one interesting specimen from the fossils my Invertebrate Paleontology class collected on their first field trip into the Upper Ordovician of southern Ohio. They did so well this week that I may be choosing a few more later! Our Fossil of the Week is the above bryozoan given the beautiful name Constellaria polystomella Nicholson, 1875. It was found by Jacob Nowell at the Caesar Creek Emergency Spillway in the Liberty Formation.
Constellaria Liberty closerConstellaria is a beautiful form, and one of the easiest bryozoans to recognize. Like all bryozooans, it was a colonial invertebrate with hundreds of filter-feeding individuals (zooids) housed in tiny tubes called zooecia. In Constellaria some of the zooecia are regularly grouped together and raised into star-shaped bumps called monticules. (The name Constellaria is clever.) This genus is a cystoporate bryozoan in the Family  Constellariidae.
JD Dana by Daniel Huntington 1858I was surprised to learn that Constellaria was named in 1846 by James Dwight Dana (1813-1895), one of the most accomplished American scientists of the 19th Century. He is best known for his Manual of Mineralogy (1848) which is still in print (greatly revised) and known as “Dana’s Mineralogy”. Dana (shown above in 1858) studied geology on scales from crystal structures to continents, with volcanoes and mountain-building in between. He had an affinity for “Zoophytes” (animals that appear to be plants), thus entangled him briefly with bryozoan systematics. Dana was born in Utica, New York, and attended Yale College, working under Benjamin Silliman, a famous chemist and mineralogist. After graduating from college he had a cool job teaching midshipmen in the US Navy, sailing through the Mediterranean in the process. For four years he served in the United States Exploring Expedition in the Pacific region. He made numerous important geological observations in Hawaii and the Pacific Northwest that he later published in books and papers. He even dabbled in theology with books like Science and the Bible: A Review of the Six Days of Creation (1856). Dana died in 1895 having received numerous accolades and awards for his research and writing.


Brown, G.D., Jr., and Daly, E.J. 1985. Trepostome bryozoa from the Dillsboro Formation (Cincinnatian Series) of southeastern Indiana. Indiana Geological Survey Special Report 33: 1-95.

Cutler, J.F. 1973. Nature of “acanthopores” and related structures in the Ordovician bryozoan Constellaria. Living and Fossil Bryozoa. Academic Press, London, 257-260.

Dana J.D. 1846. Structure and classification of zoophytes. U.S. Exploring Expedition 1838-1842, 7: 1-740.

Wooster Geologist in New Zealand

September 7th, 2015

1 IMG_0692Many of our students enjoy a semester or year abroad during their college time. Andrew Wayrynen ’17 is right now in New Zealand, one of the favorite destinations of Wooster geologists. He has generously shared some of his recent geological images with this blog. The striking section above is part of the “Pancake Rocks“, which are exposed on the west coast of the South Island of New Zealand near the village of Punakaiki. This is an Oligocene limestone that has been diagenetically altered by compaction and eroded into steep-sided shapes by freshwater dissolution and marine influence.
2 IMG_0700What looks like bedding in the Punakaiki Limestone is actually the effect of dissolution of the carbonate caused by immense overburden. One of our favorite Wooster geologists, structural guru George Davis, has a recent paper on this process (Davis, G.H. 2014. Quasi-flexural folding of pseudo-bedding. Geological Society of America Bulletin 126: 680-701.)
3 IMG_0978Andrew also visited the Moeraki Boulders on the Otago coast of the South Island. These are large spherical concretions weathered out of a Paleocene mudstone known as the Moeraki Formation.

4 IMG_0979These are septarian concretions, a type characterized by a three-dimensional network of mineral-filled cracks, as shown in Andrew’s image above.

6 IMG_0987Like the liberally-educated geologist he is, Andrew did not neglect to show the marine organisms encrusting some of the intertidal boulders. These, of course, are barnacles.

5 IMG_0986And finally, here is Andrew, happily seated on a Moeraki Boulder in a geologist’s paradise!

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