Gravel sheets in the suburbs of Washington, DC

Deborah Painter (USA) If you live in western Prince George’s County, Maryland in the USA, in the towns of Oxon Hill and Suitland and you want to dig to place a water line, plant a garden or excavate to construct a foundation for any building, chances are you will encounter sandy soil with hundreds of cobbles and boulders. Some boulders encountered could be in the form of large flattened slabs. You might be wondering why these are present, since these towns are in a coastal plain, far south and east of the rocky outcrops of the Piedmont area of Virginia and Maryland. For someone like me, who was born and raised in the Coastal Plain area of Virginia, these ubiquitous cobbles and boulders seemed out of character for the region. I discovered these odd boulders and cobbles when I joined a colleague from an office in a northern state to assist him in ecological studies for two small sites not too far from the United States Capital of Washington, in the District of Columbia (DC). Our goal was to help our client know if there were any threatened or endangered species, wetlands, hazardous materials or other site constraints, as this would assist the client to decide whether to purchase the properties. Our first Prince George’s County site for an ecological study was one of a few hectares in size in Suitland, a suburb of Washington, DC and approximately 8km southeast of the border of the capital city near the shore … Read More

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Clarkia Flora: 16-million-year-old plants offer a window into the past

Margret Steinthorsdottir and Helen K Coxall (Sweden) Near the small town of Clarkia in Shoshone County, Idaho in the USA, exists a rich and unique fossil deposit. The Clarkia fossils, or Clarkia Flora, as the deposit is mostly called due to the abundance of fossil plants, is so well preserved that the assemblage is referred to as a “lagerstätte”, a scientific term reserved for the world’s very finest fossil deposits. The Clarkia fossils are found in sediments that are now known to be about 16 million years old and belong to a period in Earth history called the Miocene. By this time, the (non-avian) dinosaurs were long extinct (the last of these dinosaurs disappeared about 66 million years ago), the Earth’s continents were more or less in the same position as today, and many of the animals and plants would have started looking familiar to modern humans (who emerged much later, about 200,000 years ago). Fig. 1. The entrance to the “Fossil Bowl” motocross racetrack and fossil locality near Clarkia, Idaho. Among the Clarkia fossils can be found various insects, fish and occasionally the remains of small mammals. However, most striking is the wealth of plant fossils in the form of exceptionally well-preserved leaves, nuts, seeds and wood. Impressively, one can find leaves of oak, laurel, pine and birch that look virtually identical to those we find today. If you look quickly when a new fossil is newly exposed from within the host sediments, you may occasionally even see the … Read More

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Boxstones: In search of Miocene Suffolk

Tim Holt-Wilson (UK) The date is 24 May 2014 and I am browsing across East Lane Beach at Bawdsey in southeast Suffolk. A brown lump of sandstone with a white fossil shell impression catches my eye. A boxstone. This is the first one I have ever found with a fossil in it. Looking closely, I see that the sea has abraded the shell’s outlines, although the margins have survived better than the rest, so it should be possible to identify the specimen (Fig. 1). Fig. 1. Boxstone, found 24 May 2014. Boxstones are fragments of a vanished world. They are all that remains of a lost geological stratum in Suffolk called the ‘Trimley Sands’ (Balson, 1990), although deposits of similar age are still present across the sea in Belgium and other parts of Europe. Boxstones are lumps or concretions of brown sandstone, which may contain shell fossils and – if you are extremely lucky – bones and teeth. They are beach-rolled and rounded, and typically measure between 5 and 15cm in diameter. The sand is mostly quartzose, with a rich assemblage of secondary minerals, and is cemented with carbonate-fluorapatite (a phosphate mineral) and calcite (Mathers and Smith, 2002). Boxstones can be found scattered sparsely across the shingle beaches at Bawdsey and Felixstowe Ferry (Fig. 2), and in situ as a common component of the basement beds (nodule beds) at the base of the Coralline Crag and Red Crag formations of southeast Suffolk (Fig. 3). They are eroding out of the … Read More

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Fossil crustaceans as parasites and hosts

Adiël Klompmaker (USA) Who would like to carry a parasite? I bet not many people would like to have one or more. They are nevertheless very common in humans and in other organisms, and can affect entire food webs including keystone species. They tend to be small compared to the host and the vast majority of them are soft-bodied. Despite their small size and soft appearance, they can affect the host substantially, for example, leading to a reduced growth rate and less offspring. Much of the same holds true for crustaceans – they are affected by parasites and can act as parasites themselves. For example, parasitic crustaceans are found among the isopods and copepods. Given the widespread occurrence of parasitism in and by crustaceans today, a fossil record of such parasitism may be expected. Swellings in fossil crabs and squat lobsters So what does the fossil record look like? I have been fortunate to have worked on this under-studied field of research. During my PhD research, I found various swellings in fossil crabs and squat lobsters (decapods from the superfamily Galatheoidea) during and after field work in northern Spain in reef carbonates from the mid-Cretaceous (upper Albian). They appeared to occur regularly in the back part of the carapaces of these crustaceans. Fig. 1. Bopyrid isopods from the species Orthione griffenis (large female and small male), removed from the right gill chamber of a modern mud shrimp (Upogebia pugettensis). (Photo by Stephen Ausmus, USDA Agricultural Research Service, http://www.bugwood.org.) This swelling … Read More

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Highlights from the Museum am Löwentor in Germany

Jack Wilkin (UK) The Museum am Löwentor in Stuttgart, Baden-Württemberg, is one of the world’s greatest depositories of fossils. The museum was founded in 1985 and, since then, it has built up a vast collection of over 4.1 million fossils and has a 3,500m2 exhibition space, spilt over two levels. It is organised in chronological order. As you progress through the building, you can trace the evolution of life on Earth from the first cells all the way to the present, telling a more-or-less complete story of Germany’s geological history. This brief article will focus on just a few of the highlights at the museum. The amber collection The museum houses roughly 30,000 amber specimens from around the world, including samples from the Dominican Republic, the Baltics and the Lebanon, to name just a few places. The highlights of the collection include the largest piece of amber in the world from the Miocene of Borneo, as well as the world’s biggest damselfly and dragonfly inclusions. Triassic vertebrates There is an extensive collection of Triassic vertebrates from Baden-Württemberg, including, not just complete skeletal reconstructions, but also realistic life models. Fig. 1. Exhibits at the museum.One group that is featured in the exhibit were the placodonts – an enigmatic group of marine reptiles that superficially resemble turtles, although the two groups are unrelated. Many species, such as Placodus gigas, had large, flat teeth designed for crushing shells. The apex land predator of Central Europe at the time was the 5.6m, Batrachotomus. It … Read More

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Jamaica’s geodiversity (Part 1): Introduction and some older highlights (Cretaceous to Miocene)

Stephen K Donovan (The Netherlands) and Trevor A Jackson (Trinidad) With a length of only about 240km, Jamaica cannot be considered a large island. It is also relatively ‘young’ geologically, the oldest rocks being only about 140myrs old. This might sound old enough, but contrast it with, for example, rocks in the islands of the Scottish Outer Hebrides, which are about 2,000myrs old. But Jamaica is nevertheless noteworthy in having a rich diversity of rock types and geological features, and it is rightly known for its high biodiversity, both on land and in the surrounding seas. To give one example, the 500 or more species of extant land snails make Jamaica a biodiversity ‘hot spot’ for these familiar molluscs. However, Jamaica should similarly be recognised as a geodiversity hot spot, with a range of geological and physiographic features, strata and fossils that make it an unusually fruitful focus for earth sciences research. We could support our bold assertion by a detailed exposition with tabulation of principal features and comparison with similar-sized islands elsewhere, although such an approach would perhaps be better suited to a dry research journal. The potential for producing such a long, boring discursion is large and we intend to avoid the temptation to do so. Rather, we want to illustrate Jamaica’s geodiversity by reference to a dozen key features. These are available for inspection to anyone who is interested and which we will describe in two articles in Deposits. The choice of these features is personal – … Read More

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Geoscience highlights from the Harvard Museum of Natural History

Ruel A Macaraeg (USA) Harvard University in Cambridge, Massachusetts, is among the world’s leading academic institutions and natural science is one of its most celebrated programs. Since its founding in the seventeenth century, the university has been a repository for specimens of scientific curiosity. Over time, these grew into three comprehensive reference collections – the Museum of Comparative Zoology, the Harvard University Herbaria and the Harvard Mineralogical Museum. Selections from these were eventually gathered into the Harvard Museum of Natural History, which, in 1998, opened to the public alongside the Peabody Museum of Archaeology and Ethnology with which it shares a building. Though retaining separate names and administration, the HMNH and PMAE are physically connected, and visitors to either gain entry to both with a single ticket. As one of these more recent visitors, I will share some brief impressions of the major palaeo and geoscience exhibits below. Mineralogical and geological gallery Geology displays worldwide tend to look the same – rows of labelled rocks grouped into categories in ascending shelves. Harvard’s geological gallery follows this pattern, but is distinguished by the inclusion of several large and notable mounts. Chief among these are two very large rocks, a gypsum crystal (Fig. 1) and an amethyst (Fig. 2). Fig. 1. Gypsum. Fig. 2. Amethyst. There are also several, well-preserved meteorites from locations across North America, some of which are shown in Fig. 3. Fig. 3. Meteorites. Fossil mammals A narrow, winding hallway somehow manages to display quite a few large Cainozoic … Read More

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West Coast Fossil Park, Western Cape, South Africa

Margaret A Dale (UK) While planning a touring holiday, which encompassed part of the west coast of South Africa, I spotted the words “fossil park” on the map, about 150km north of Cape Town, some distance from a village called Langebaanweg. Intrigued to find out more, I searched the Internet to determine if it was accessible to the public and, if so, its opening times. I found nothing. Not to be deterred, my husband and I decided that, once we were in the country, the usual tourist literature would give us the required information. Unfortunately, once again, there was nothing. So, determined not to be defeated, we drove to the area in the hope we could find it and visit it. Fortunately, we managed both. The fossils in the park date back to the late Miocene and early Pliocene eras (Fig. 1). These are important periods in human evolution, since it is believed that the last common ancestor of humans and our closest living relatives – chimpanzees – lived during this period. Mio-Pliocene hominid fossils are extremely rare and have only ever been found in East Africa and not among the deposits found at the West Coast Fossil Park to date. Fig. 1. One of the many partly excavated fossil beds. With more than 200 different kinds of animals being identified, the park possibly represents: The greatest diversity of 5 to 5.2myr-old animal fossils found anywhere in the world; andThe richest fossil bird site older than 2myrs in the world.The … Read More

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On fossil beaked whales, phosphorites and ocean floors

Klaas Post (The Netherlands) In 2007, the vessel, Anita, was fishing with bottom gillnets in about 400m-deep waters northwest of the island of Mykines in the Faroe Islands (about 62˚05’N-09˚28’W). One day, fisherman Bjarni Jacobsen from the village of Sumba in the Faroe Islands, observed a strange object in the nets. At first sight he thought it was a peculiar stone (stones often get entangled in the nets). However, he soon realised that it had to be something different and put the object aside. He later believed it to be a bone or a head of a large animal or reptile and – acknowledging that fossils of large mammals or reptiles are unknown in the Faroe Islands – handed it over to a local museum. After time and much travel, the enigmatic object was identified as a rostrum – the anterior part of the skull – of the 10 to 8myr-old extinct beaked whale, Choneziphius planirostris (Post & Jensen, 2013). Fig. 1. The Anita rostrum; dorsal and lateral view.Beaked whales The shy, deep diving and squid-eating beaked whales (Ziphiidae) are, after the dolphins (Delphinidae), the most species-rich family of extant cetaceans (with 22 living species). Their obscure behaviour is the reason that some of the species were – until a few years ago – never seen and just known from skulls found on distant beaches. They range from medium sized (3m – the pygmy beaked whale, Mesoplodon peruvianus) to up to very large animals (12m – Baird’s beaked whale, Berardius … Read More

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Miocene, mud and more: Miste 2013

Bram Langeveld (The Netherlands), Colin van Elderen (The Netherlands) and Stef Mermuys (The Netherlands) ‘Miste’… This word has an almost magical meaning for many fossil collectors in The Netherlands and neighbouring countries. That is because the extremely fossiliferous Miste Bed lies close to the surface around the municipality of Winterswijk-Miste, which, in turn, lies close to the Dutch-German border in the Eastern Netherlands (Fig. 1). The Miste Bed (Aalten Member, part of the Breda Formation) was deposited about 15Ma (during the Middle Miocene), in a shallow subtropical sea. The fossils preserved in the sandy sediments are extremely diverse: over 600 species of molluscs (Janssen, 1984; Parren, 2005) and dozens of species of sharks, rays (Bor et al, 2012) and bony fish (Hoedemakers and Van Hinsbergh, 2013) have been found, but also marine mammals (Schneider & Hessig, 2005), sea stars (Jagt, 1991), sea urchins, bryozoans and corals. Fig. 1: Overview of the Miste dig, with many enthusiastic collectors (photo by Ronald Pouwer). Inset: map of The Netherlands (drawing by Jerry Streutker) showing the location of Miste (red dot). However, this fossil wealth is not easily accessible. To be able to assemble a decent collection, you need to dig a rather large exposure. Establishing a large hole reaching into the Miste Bed is a lot of work, because you need to excavate approximately 4m on private property. A number of digs have previously been organised at Miste, of which at least three were by the Dutch ‘Werkgroep voor Tertiaire en Kwartaire Geologie’ … Read More

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Palaeocene lagerstätte in France

Dean Lomax (UK) A Lagerstätte is a sedimentary deposit that exhibits exquisite fossil richness, detail and/or completeness, often preserving fine details, including soft parts, which wouldn’t normally be found as fossils. There are two main types of fossil Lagerstätten: concentration Lagerstätten, which simply consists of large concentrations of fossils found together in deposits such as bone beds; and conservation Lagerstätten, where the defining feature is the preservation of quality rather than the quantity of fossils. A few examples of famous Lagerstätten include the Eocene Green River Formation, which is primarily known from Wyoming, but can also be found in Colorado and Utah. Famous European Lagerstätten include the Solnhofen Formation of Bavaria, Germany. This has produced some spectacularly preserved fossils, including Archaeopteryx, which is considered to be a transitional fossil between dinosaur and bird evolution. Another famous Lagerstätte, situated in central Germany, is the Messel Pit (Grube Messel). This quarry contains Eocene-aged strata and has produced specimens such as Darwinius masillae, identified as a basal primate and described in 2009. Fig. 1. A group searches for fossils in one of the privately owned quarries. (Photo by Dean Lomax.) Geological setting and location Menat is a small village located within the department of Puy-de-Dôme, Auvergne in central France, near the town of Gannat, a town famous for Oligocene and Miocene-aged fossil deposits. The geology of Menat consists of sedimentary rock that includes soft shale layers (including bituminous, pyritious and oil shales) and hard layers consisting of diatomite. The preservation of the fossils … Read More

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Coping with coprolites

Carl Mehling (USA) Generally, we have no use for it, or at least we convince ourselves we don’t, conveniently ignoring the fact that faeces of one kind or another (even our own) have fertilised our food for millennia. Organic waste products are an integral part of the living system and don’t tend to sit around for long. And it’s a good thing too, because, without the recycling of waste in Nature, we’d certainly be swamped by the stuff. Fig. 1. Ammonnite chamber steinkern composed of tiny invertebrate coprolites (Carl Mehling). Fig. 2. A probable Cretaceous crocodililian coprolites Fig. 3. The real thing? (Carl Mehling). Alas, this is a problem for students of coprolites – those droppings from Deep Time – as it reduces the probability of good coprolite fossils. However, everything in Nature has a story to tell, and there’s usually someone eager to listen, whomever or whatever that storyteller might be. I am one of those palaeontologists drawn to make order out of ordure and, thanks to the whims of the fossil record, enough of these now-inoffensive offerings have fortunately survived to the present. Fig. 4. A Triassic coprolite filled with fish bones (Carl Mehling). My first coprolite emerged from the Late Cretaceous marine sediments of Big Brook, New Jersey. It was a coprolite of spiral morphology – surprisingly common, once one’s search image is tuned – which my mentors credited to a shark. All ‘experts’, both amateur and academic, reflexively parroted this identification. Later, I learned that other … Read More

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