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Artist unknown: The dilemma of the Nottoway Stone Image

About 61 years ago, a boy wandered among loblolly pines near an agricultural field not far from the Nottoway River in southern Virginia in the USA. His eyes fell upon a tan coloured rock atop a thick layer of old needles at the bases of the pines. It was a curiosity – the coastal plain Southampton County does not feature rocks reposing at the surface. Young Lloyd Bryant turned over the rounded chunk of stone and was jolted to see an etched human face staring back (Fig. 1).

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Shining hill in the Arizona desert

Deborah Painter (USA) In the area east of the small community of Bagdad and on the northeast edge of the Arrastra Mountain Wilderness of central Arizona in the USA, my friends, Terril, Yvette and David, stood with me at the base of a vision in the desert of a rockhound’s dream. This was a colourful, irregularly shaped hill, standing alone in the arid wildlands, its bright whites, reds and greens standing out against a blue and white March sky. The entire hill seemed composed entirely of loose stones of quartz, caliche (a mineral deposit of gravel, sand and nitrates found in dry areas of the USA), basalt, travertine, green quartzite, tuff and gabbro. One whole side of the hill was white from quartz. We had attempted to climb this amazing thing. But, like wonderful things in a dream, most of it eluded us. We could climb but a metre or so, before we slid back down, unable to secure a foothold. However, the four of us collected about a bucket full of the rocks on this Bureau of Land Management land. Fig. 1. Our eyes were transfixed by a shining green, brown, red and white hill (a volcanic neck), standing alone in the Central Highlands of Arizona. The side facing east (to the right in this photograph) was white from quartz. (Credits: Deborah Painter.) Just across the roadway to the south, we had hiked a short distance across an arroyo (a Spanish word for a dry creek or stream bed). … Read More

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Very down-to-earth Vasquez rocks portray the surface of alien planets for the media

Deborah Painter (USA) They have become associated with stark alien or other-dimensional landscapes since the 1960s, when the popular American television programme Star Trek used them as dramatic backdrops in two episodes, “Arena” and “Friday’s Child”. Prior to that, the Vasquez Rocks of Agua Dulce in California were a favoured location for American Western programmes, such as Branded, Cheyenne, Zorro and The Adventures of Champion, as well as motion pictures like One Million BC (1940) and Apache (1954), when rocky areas with hiding places, wide overlooks and an overall arid, rugged look were needed. More recent films and television programmes tend to exploit their odd appearance (Star Trek IV: The Voyage Home (1986), Army of Darkness (1993) and John Carter (2012)). Some films with no fantasy elements also use the rocks as a backdrop, one example being the family “road” comedy, Little Miss Sunshine, released in 2006. Fig. 1. The much-photographed side of the Vasquez Rocks pinnacle and main film staging area. (Photo: Michael Ramsey.) In fact, the Vasquez Rocks now have the distinction of being an overexposed outdoor location simply because of their proximity to the big city of Los Angeles’ filmmaking industry, hence their presence in scores of films, television programmes and music videos. Only about 64.5km from Los Angeles, the Vasquez Rocks are off State Highway 14, between Acton and Santa Clarita in California, USA and can be seen from Highway 14. The signs will direct the motorist to the exit that leads to the Vasquez Rocks … Read More

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Golden Dinosaur from the depths of the London Mine: Mystery of Genevieve

Steven Wade Veatch and Teresa L Stoiber (USA) The legend of “Genevieve”, a fossilised dinosaur not only made of stone — but also of gold — began on 3 July 1932. That was the day WK Jewett, owner of the London Mine near Alma in Colorado, stopped at the Antlers Hotel in Colorado Springs and made the official announcement of its unearthing. The story was picked up by the news services and word of the fantastic find spread through the scientific world like a prairie fire. The golden dinosaur was discovered by William White, 700 feet (213m) underground — deep in the London Mine (WK Jewett, 1932). Curiously, the miners had been using the creature’s nose as a lamp holder, not realising there was a ‘dinosaur’ (if that is what it was) there. White, a hard rock miner, believed at first he was looking at two stumps. In reality, it was a dinosaur lying on its back with its limbs at an angle of 75 degrees. Eager to retrieve it from its rocky tomb, miners blasted it out of rock at the 700-foot level of the London Mine with dynamite. The blast shattered the specimen. Bits and pieces of the dinosaur were hoisted to the surface, where curious crowds gathered to see the prehistoric monster. As the story goes, a geology professor at Colorado College, Robert Landon, travelled to Alma so he could examine Genevieve – an extraordinary record of a former world. The measurements he made revealed that the … Read More

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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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Rudists: A fossil story

Jack Shimon (USA) This article is adapted from a presentation given at the Denver Gem Show, September 17, 2016 by me, Jack Shimon. When I was six and a half years old, my Grandpa took me fossil hunting in central Texas. We went to a Carboniferous Limestone quarry that he had visited earlier and was given permission to enter and collect from. This was one of my first fossil hunting trips and I really enjoyed it. The ancient reef we went to (now a quarry) had huge boulders of limestone and tube-like things in it we later to be found to be rudist bivalves. This article is all about these finds and the efforts we went to, to find out what they were. Fig 1. The author at the quarry. (Photo credit: Mike Hursey.) Fig. 2. This Google satellite image shows the reef we collected from. Two of the three lobes have been excavated for limestone. You can also see smaller pinnacle reefs marked with the short arrows. All of the reefs rise above the flat Texas landscape. (Permission from Google.com: ‘Special Use Guidelines’.)Fossils We spent a lot of time at the quarry observing the massive specimens onsite and then collected some smaller pieces to bring home and look at closer. A simple way of thinking about fossils is to consider them either as a cast or a mould. A mould is formed when an object is placed into a soft substrate and then decomposes or is washed away leaving … Read More

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Important Green River Formation fossils come to New York

Stuart Wilensky and Douglas Miller (USA) In the early Eocene Epoch, drainage from the newly uplifted Rocky Mountains filled an inter-mountain basin to form what geologists call Fossil Lake. The climate of Fossil Lake was subtropical, similar to the climate of Florida today. The lake persisted for about two million years, and was home to palm trees, turtles, birds and an abundance of fish. On numerous occasions, unique conditions came together to result in some of the best-preserved fossils ever discovered. The sediments of Fossil Lake were first discovered in the 1860s, near the town of Green River Wyoming, and the area was named the “Green River Formation,” which is well-known in the scientific community and by amateur collectors. Palaeontologists have long theorised that the lake was deep enough to be anoxic (devoid of oxygen) at the bottom. This prevented scavengers from disturbing the plants and animals, and inhibited decomposition. Algae, and other plant and animal life, would die and fall to the bottom as in lakes and ponds today. Storms brought runoff from the mountains, covering the flora and fauna with mineral-rich material that would ensure their preservation. Recently, scientists have asserted that a kind of “red tide” may have been responsible for the many perfectly preserved fossils found. (“Red tide” is a common name for algal blooms, which are large concentrations of aquatic microorganisms, such as protozoans and unicellular algae. These can cause a severe decrease oxygen levels in the water column, leading to mass mortality events.) We … 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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Colourful bluffs in Long Island recall the most recent ice age

Deborah Painter (USA) Imagine a tremendous piece of land moving equipment that scraped up the soil and some of the surface bedrock from four states within the United States’ Eastern Seaboard, carrying and dragging it all the way, before dumping it on a ridge off the shoreline. That is what essentially occurred with the final advance of the Wisconsinian ice sheet, the only one which left glacial deposits visible in New York State today. Long Island is a ridge of Cretaceous bedrock with glacial deposition. The moraines there have not been ground into sandbars and spits along the western end of the north shore as much as elsewhere, because of the sheltered nature of the Long Island Sound. Therefore, shoreline bluffs expose rocks as well as glacial loess. Fig. 1. Fishermen’s Drive takes you to the loess deposits. To park at the beach requires a permit. (Photo by JB Steadman.) If you find that your journeys take you to New York City, one of the world’s largest metropolitan areas, try to make time to visit Caumsett State Park at Long Island Sound. My own visit began when planning a visit to New York State’s Long Island to see my friend, Joyce Raber. She suggested various things that we might do: go to a Broadway play, go shopping and so forth. However, my list of things to do was typically “eco-tourist”. I wanted to visit the famed American Museum of Natural History in Manhattan, then see nearby Central Park, where the … Read More

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Colorado mountain memories

Steven Wade Veatch (USA) While headed for the California Gold Rush of 1849, George Giggey (who was my great-great-grandfather) first made his way through the mountainous and untamed wilderness of what would later become Colorado. He was among a group of young men, who were determined to make a new life, fortune and future in the American West. After working in the Californian goldfields, he turned his attention to Colorado, where he prospected for gold for a while and then returned to the East. In 1865, George Giggey returned to Colorado with his family of ten children and built a homestead in the wilderness near what would become, in just a few years, the town of Caribou. The town developed around the Caribou silver mine that was discovered by Sam Conger in 1868. George Lytle, one of Conger’s partners, was from British Columbia and named the mine after his caribou hunting trips in Canada. By 1870, the Caribou Mine was in full production and was shipping ore down Coon Trail, to the nearby settlement of Nederland for processing. By 1872, the frontier town of Caribou built a much needed schoolhouse. Three of George Giggey’s boys attended Caribou’s first school session. They were: George Leon (my great-grandfather), who was 14 years old; Adelbert, age 7; and Charley, who was only 6 years old. I can feel the boy’s excitement when they took their seats in the one-room schoolhouse, with new furniture, blackboards, maps, globes and a new teacher – Miss Hannah … Read More

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Volancoes of Big Island, Hawaii (Part 3)

Dr Trevor Watts (UK) This is the last of a three part article about the volcanoes of Big Island, Hawaii. In the first part, I discussed their background and explained some of the terms used to describe the lava that can been seen there. In the second, I discussed some of the highlights that my wife and I saw during our several trips to the island, including in October 2014. And in this part, I will continue to describe what we saw. Fig. 1. One of the kipukas (that is, untouchedby- lava areas of forest). The abandoned lava cliff at Kalapana This is a stretch of old cliff face that is now several hundred metres from the sea. It is located among the flows of February 1992 to October 2003, but the area was re-flooded with lava between 2007 and November 2013, when the ocean entry hereabouts was blocked. The site is just under 5km southwest of present-day Kalapana near Poupou, where the Royal Gardens lava flow reached the coast. The walk is well worth the effort for the variety of lava formations, the many tumuli or blisters of lava, and the coastal scenery along the present cliffs. We were guided here by Gary Sleik, who lives on the lava at Kalapana. Fig. 2. The first section of cliff face, with the lens-shaped tube blocked by cindery flow. The cliffs are backed up by a small kipuka, which is an area that was left untouched, as the lava flowed around … Read More

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Volancoes of Big Island, Hawaii (Part 2)

Dr Trevor Watts (UK) This is the second of a three part article about the volcanoes of Big Island, Hawaii. In the first, I discussed their background and explained some of the terms used to describe the lava that can been seen there. In this part, I will discuss some of the highlights that my wife and I saw during our several trips to the island, including in October 2014. A night walk to the flowing lava from Kalapana This was one of the major highlights of our previous trip in 2013. Several local guides conduct walks across the old lava (mostly 1981 to 2013 flows) to wherever the current flow is best viewed. Our lead guide was Dave Ewing (postewing@gmail.com or (808) 315-2256) and our group met up at his house, located on private properties beyond the “End of the road” signs at Kalapana. This house is one of the very few to survive the 2010 flow, which came through the Royal Gardens subdivision and into Kalapana. Fig. 1. A going away party to mark the long-expected event of the house burning at Kalapana on the night of 25 July 2010. My thanks to Darlene Cripps and Gary Sleik for this picture. We began in late afternoon, with around a dozen people in the group. The walk initially passed the remnants of some of the other homes – a corrugated roof, a fridge, some pilings, and so on, before getting onto the fresh lava. It was almost five kilometres … Read More

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Volancoes of Big Island, Hawaii (Part 1)

Dr Trevor Watts (UK) We (my wife Chris and I) enjoyed our fourth visit to Big Island Hawaii in May 2013 so much that we decided to return to the same places in October 2014. We were hoping to see similar events and activities, which we had found particularly interesting and accessible over the years. Every time we visit, something changes or isn’t possible, but this time was a little more changeable than most. The intervention of three ladies altered a few of our plans – Iselle, the hurricane that visited the southeast of Big Island two months before we arrived; Madame Pele, the Hawaiian Goddess of the Volcano; and Ana, the hurricane that hit the area during our stay. The three interventions illustrate the simple fact that we and our little plans have to be adaptable and show that some of the great locations will be discussed in these articles and will be missed if you only make one visit. This is the first of three articles on Big Island in Hawaii. In them, I will talk about the major highlights of our visit in connection with the volcanic activity of this wonderful island. This first part will mostly illustrate the different volcanic concepts that need to be understood to appreciate what can be seen, and will also provide a general background to the location and the significant summer 2014 flow towards Pahoa. About lava Traditionally, lava is described as pahoehoe or a’a. These are taken to mean ropey … Read More

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Great Plains geology: A personal journey

Professor Emeritus Robert F Diffendal, Jr (USA) I grew up in the 1940s and 50s in the eastern US state of Maryland and went to cinemas on my own from the age of six, mostly to see what were then to me exciting western movies. In 1962, I was off to graduate school in the Great Plains state of Nebraska, a place that I pictured in my mind as it had been depicted in some of those films. Imagine my surprise when it looked nothing like the outdoor scenes in most of those films. Silly me, to have thought that films were made as closely as possible to the real subject area. From graduate school in 1962 to now, I achieved my goals and became a geologist and professor, travelling and doing research in the Great Plains and western Central Lowland physiographic provinces, and looking at geology in exotic places like the UK, China, Australia and New Zealand. Fast forward to 2013. I had enough experience and expertise on Great Plains geology by then that I was asked to write a short book of about 35,000 words on the geology of the Great Plains by the director of the Center for Great Plains Studies at the University of Nebraska, Dr Richard Edwards. After visiting and studying sites in Alberta and Saskatchewan in Canada, and in south-western Texas that I had not previously studied, I started working on the book now titled Great Plains Geology that is reviewed in this issue … Read More

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Fulgurites: With the look and shape of lightning bolts

Deborah Painter (USA) If the characteristics referred to in the title were their only quality, fulgurites would be fascinating. However, they have other unusual qualities that make them even more amazing. For example, some hold ancient air within that can offer a window into palaeo-environments. Fulgurites are natural tubes or, in the case of rock fulgurites, crusts of glass formed by the fusion of silica (quartz) from a lightning strike. They are categorised in four main types: clay, sand, caliche and rock fulgurites. In the case of the sand or clay fulgurites, the shape mimics the path of the lightning bolt as it enters the ground. All lightning strikes hitting the ground are capable of forming fulgurites, but not all lightning strikes will do so. A temperature of 1,800oC is required to melt sand and form a fulgurite, but this is not usually an impediment, since most lightning strikes have a temperature of 2,500oC. Fig. 1. North Carolina’s sand dunes are a popular place to find sand fulgurites. (Photo by D M Maxos.) In addition to the four main types mentioned above, there are the droplet fulgurites, which obviously resemble droplets, but, in composition, are similar to the clay and caliche fulgurites. Sand fulgurites tend to have rather fragile glass walls. Rock fulgurites are found not as discrete structures, but as veins or branching channels on a rock surface, or as a lining of fractures, which existed before the lightning strike. Fig. 2. A large (9cm) specimen. (Photo by Mark … Read More

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Worm monstrosity: A giant extinct worm

Mats E Eriksson (Sweden) In a new study published in Scientific Reports (Earth’s oldest ‘Bobbit worm’ – gigantism in a Devonian eunicidan polychaete) by Luke A Parry of Bristol University in the UK, David M Rudkin of the Royal Ontario Museum in Canada and me (Mats E Eriksson of Lund University in Sweden), an extraordinary new species of polychaetes (that is, bristle worms – the marine relatives of earthworms and leeches) is described. The new species, Websteroprion armstrongi, is unique among fossil worms and possessed the largest jaws recorded from all of earth history, reaching over one centimetre in length and thus easily visible to the naked eye. Typically, such fossil jaws are only a few millimetres in size and must be studied using microscopes. Despite being only knows from the jaws, comparison of Websteroprion armstrongi with living species suggests that this animal achieved a body length in excess of a metre. This is comparable to that of ‘giant eunicid’ species, colloquially referred to as ‘Bobbit worms’, a name that is bizarrely enough derived from the infamous story of eye-watering amateur surgery involving Lorena and John Wayne Bobbitt. Living ‘Bobbit worms’ are fearsome and opportunistic ambush predators, using their powerful jaws to capture prey, such as fish and cephalopods (squids and octopuses), and drag them into their burrows. Fig. 1. A photograph showing the holotype of Websteroprion armstrongi. (Photo by Luke Parry.) Gigantism in animals is an alluring and ecologically important trait, usually associated with advantages and competitive dominance. It … 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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New look for Utahraptor

Kenneth Carpenter (USA) One hundred and twenty eight million years ago, a killer stalked eastern Utah. Known as Utahraptor, this distant relative of Velociraptor of Jurassic Park fame was also equipped with a sickle-claw on its hind feet. The name means “Utah’s raptor” with “raptor” being the informal name commonly (but incorrectly) used for the sickle-clawed dromaeosaurid theropods. Utahraptor was named in 1993 by Dr James Kirkland for bones from the Gaston Quarry (also known as Yellow Cat Quarry), north of Arches National Park. The Gaston Quarry occurs in the lower part of the Yellow Cat Member of the Cedar Mountain Formation. The presence of an ankylosaur related to Polacanthus at the Gaston Quarry suggests that the Yellow Cat Member is the same age as the Wealden Formation on the Isle of Wight, in other words, it lived 125 to 130mya. A radiometric date of 126 +2.5mya was obtained from the Yellow Cat Member which supports the dinosaur evidence for the age. Utahraptor has been found at several other sites in the Yellow Cat Member, so must have been relatively widespread in the region. Nevertheless, most of this material remains undescribed. Fig. 1. Some of the bones used in the original description of Utahraptor (scale is 10cm). Casts of these and other bones were used to make a new reconstruction. Until recently, what Utahraptor looked like relied a great deal on imagination. Several recent scientific studies have shown that Utahraptor is related to Achillobator, a dromaeosaurid from the middle of … Read More

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Dinosaur track investigation

Jack Shimon (USA) My “Fossil Grandpa” took me to visit this neat site when I was in Texas last summer (2013). We drove to a small rural community, where it seemed there wasn’t anything to find. However, my Grandpa pointed out me to a small trail, full of flowers that Jane (my sister) had stopped to admire, which eventually led down a steep trail into the riverbed. This was definitely not a popular hiking trail and I doubt many people (except geologists) have been to this spot. The site is an ‘Earthcache’, which, in the USA, is a type of geological site that teaches you about a unique geoscience feature. I have been to several Earthcaches in Texas and to at least four in other states (Colorado, Iowa, North Carolina and Florida); and have learned some interesting lessons. Here, our job was to study the dinosaur tracks and answer some questions. Fig. 1. Jane and me at the dinosaur tracks. We are each standing by a footprint. (Photo by Julie Shimon.) What type of dinosaur made these tracks? A theropod like Velociraptor or T-rex, or maybe even the recently discovered Lythronax argestes? It must have been some type of carnivorous predator; and to think I was standing right where it walked so long ago. It was a little frightening to imagine one coming along and what that would be like in real life. Fig. 2. Dinosaur track. (Photo by Julie Shimon.) The first task was to measure the stride. The … Read More

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Geology of islands

 Stephen K Donovan (The Netherlands) Islands are attractive places to visit, not just for geologists. Nonetheless, for us, they provide three advantages that favour collecting and research in the Earth Sciences. One of the attractions of an island is its small size in comparison with continents. The corollary of this small size is its relatively long coastline. Assuming that our island is not the mound of sand with a palm tree so loved by cartoonists, a long coastline indicates abundant exposures of rock, commonly well-exposed and accessible. Second, because of their relatively small size, islands offer a limited possible area of outcrop. The island may be volcanic in origin, so you may have one (or a few) volcanoes and its deposits to map, log and sample, producing a self-contained study. A particular sedimentary deposit may be (probably will be) limited to a single island. If you want to determine the palaeontology or palaeoenvironments of this deposit, the only place it can be studied is on one island. To give one example (among many), the Middle Miocene Grand Bay Formation, exposed on the east coast of Carriacou in the Grenadines, Lesser Antilles, includes the only crinoid-rich deposits in the Caribbean Islands. I had been studying the few Antillean fossil crinoids for ten years until I went to Carriacou and the sum total of specimens I had collected until then could have rested, comfortably, in the palm of one hand. From Carriacou, I collected bags of crinoid-rich bulk sediment samples (Donovan and … Read More

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Nebraska, USA: Wonderful fossils, natural history museums and public art depicting fossils

Robert F Diffendal, Jr (USA) Nebraska is known by vertebrate palaeontologists as the place in North America where there is a very complete Cenozoic geologic record of mammalian evolution over the last thirty-five million years or so. All you have to do is visit any of the many major natural history museums in the USA and in many countries around the world, including the UK, to see fossil skulls, articulated skeletons and large slabs of rock containing bones of fossil mammals from Nebraska to verify this assertion. Nebraska is also the site of Cretaceous rocks containing the oldest known Cretaceous fossil flower and many other parts from fossil plants. It also contains dinosaur footprints and trackways, and skeletons of marine plesiosaurs, mosasaurs and large marine fish, as well as terrestrial and marine invertebrate fossils and marine microfossils. Upper Carboniferous rocks exposed at the surface in parts of south-eastern Nebraska have yielded fossil terrestrial plant fossils, marine stromatolites and other marine plant fossils, marine invertebrates, fish and even some fossil bones of amphibians and early reptiles. All in all, Nebraska is a vast storehouse of wonderful fossils that continues today to yield them up to collectors, both professional and amateur. These fossils can be found on both private and public lands, and in state and federal parks and museums. To match this geological heritage, Nebraska (a large state in area with a small population) has a wonderful natural history museum – the University of Nebraska State Museum (UNSM) – on the … Read More

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Ute arrow straightener made of Jurassic dinosaur bone

Gavin Noller (USA) I am currently studying an arrow straightening tool left behind by the Ute Indians of the Northern Colorado Plateau long ago. The artefact is made of an unusual material – a Jurassic dinosaur bone. As I work with this object (which is more than 13 decades old), I imagine a scene when it was used: A group of Ute braves are sitting on a forested mountain slope that overlooks the plains where the braves and their families have camped. They are manufacturing arrowheads and straightening the shafts of their arrows for hunting. The day is quite peaceful. The sun is shining – showering the landscape with its blissful, gratifying warmth and light. In the distance, the dark silhouette of a herd of grazing bison is visible. One brave – Leaf Who Rides on the Wind – has a tool for straightening the shafts of arrows. It is made of a peculiar material that is like bone, but is as hard as rock, and all the other braves believe it contains great medicine. The arrow straightener that Leaf Who Rides on the Wind uses is part of a large dinosaur bone. The bone was smoothed, so it could fit into his hand. A single long groove was put in to the bone to straighten the shafts of arrows, so they would hit their intended target, straight and true. Fig. 1. View of arrow shaft straightener made of dinosaur bone from a Jurassic bone bed. (From the G Noller … Read More

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Florissant fossil spider discovery

Zachary J Sepulveda (USA) and Steven Wade Veatch (USA) The Florissant Fossil Beds National Monument is known worldwide for its late Eocene (34Ma) fossil plants and insects. Recently, a fossil spider was discovered at the commercial quarry, which is near the fossil beds (Fig. 1). Due to the condition of the fossil, it can only be assigned to the family Lycosidae (see table) (Rasnitsyn, 2012). If correct, this classification would make it a wolf spider. This fossil wolf spider lived 34Ma under Florissant rocks, within the forest litter or on short herbaceous plants (Meyer, 2003). Based on its modern relatives, it would have had colours that helped camouflage it, allowing it to hide from its prey (Meyer, 2003). According to the Florissant Fossil Beds National Monument fossil database, only one other member of the family Lycosidae (from the Greek word for ‘wolf’) has been discovered there. Petrunkevitch (1922) described this fossil and assigned it to the species Lycosa florissanti, from a well-preserved fossil specimen. Spiders belong to the class Arachnida. Unlike insects, arachnids have eight legs instead of six, have two body sections instead of three, and do not have antennae or wings. Taxonomy of wolf spider from the Florissant Fossil QuarryKingdom:AnimaliaPhylum:ArthropodaSubphylum:ChelicerataClass:ArachnidaOrder:AraneaeSuborder:LabidognathidaeFamily:LycosidaeThese spiders are incredibly successful – with a lineage stretching back millions of years. With over 100 genera and 2,300 species, they are capable predators spread throughout the entire globe and can inhabit almost every type of environment. From shrub lands to coastal forests, from gardens to alpine meadows, … Read More

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Geology of East Greenland

James Cresswell (UK) Eighty percent of Greenland is covered by ice and, in places, this is up to 3.4km thick. So, Greenland might not immediately spring to mind as a place to go to observe rocks. However, it is a huge country and the ice-free area, at 410,000km2, is nearly twice the size of the UK. This is generally sparsely vegetated, leaving the rocks beautifully exposed and the geology incredibly easy to see. The area of East Greenland around Scoresby Sund, Kong Oscar and Kejser Franz Joseph Fjords is the largest ice-free area in Greenland. It also has incredible geodiversity, with basement rocks as old as three billion years, an almost complete sedimentary record of the last 1.6byrs and huge volumes of flood basalts from the splitting of the Atlantic. If you were an alien and wanted to try to piece together the geological story of Planet Earth – but could only visit one area – East Greenland would be the place to go. Fig 1. A simplified geological map of East Greenland. The geological history of Greenland is vastly long and spans 3.8byrs. Its oldest rocks are the 3.8byr-old Isua Complex, situated in West Greenland, near the capital Nuuk. These rocks are the Earth’s oldest, most well-preserved sedimentary and volcanic rocks, and they contain carbon particles that most likely originate from the oldest known life on the planet. To put into perspective just how old these rocks are, try to imagine that the planet is only one year old. … Read More

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Utah: A geologist’s wonderland

Chetan Patel (USA) Often referred to as the Red Rock Country, the state of Utah boasts some of the most breathtaking landscapes formed from years of erosional artistry. Dominating this impressive landscape is the Colorado Plateau that spans the four states of Colorado, New Mexico, Arizona and Utah. Adjacent to the Colorado Plateau, separated by the Wasatch Fault Zone, is the Basin and Range Province, another expanse of geological wonder formed during the Laramide Orogeny. These spectacular landscapes, dominated by the eponymous red rock, offers geologists a great opportunity to study both modern and ancient processes in great detail. With favourable weather and easily accessible outcrops, Utah serves up an exciting geological journey. Fig. 1. Map showing extent of the Colorado Plateau. Within Utah, resides what is commonly referred to as the mecca of sequence stratigraphy, the Book Cliffs. These offer a wonderland of stratigraphic sequences to the travelling geologist. In fact, hosting a wide variety of easily-accessible outcrops, Utah has become a premier location for the study of sequence stratigraphy, specifically in the oil and gas industry. The well-exposed outcrops offer a detailed look into facies relationships providing the perfect outcrop analogues to subsurface exploration. The name “Book Cliffs” was coined by the early settlers of the region to which the alternating layers of shale and sandstone resembled the pages of a book on its side. Fig. 2. The Book Cliffs in the foreground. The Book Cliffs lay within the Colorado Plateau, with the escarpment spanning over 250km and … Read More

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Book reviews: Fossils on the floor in the Nebraska State Capitol

Nebraska has an excellent geology record, which is celebrated by some fine mosaics at the Nebraska State Capitol. When the building was being constructed, and at the request of Prof Hartley Burr Alexander of the University of Nebraska Philosophy Department and from drawings by his colleague Dr Erwin H Barbour (former director of the University of Nebraska State Museum), the artist, Hildreth Meière, was asked to create a series of mosaics.

Geology of the Falkland Islands

Phil Stone (UK) Plate tectonics have produced some surprising juxtapositions, as the earth’s continental fragments have drifted and jostled over the eons. Microplates seem to have enjoyed most freedom of movement and none more so than that supporting the Falkland Islands. Though this archipelago is situated in the south-west corner of the South Atlantic Ocean, about 650km east from Tierra del Fuego and the Strait of Magellan, its geology tells of an African heritage. Charles Darwin provided the first evidence for that – although he didn’t appreciate it at the time. Fig. 1. A reconstruction of the Gondwana supercontinent at about 300mya. (© BGS/NERC.) HMS Beagle visited the Falkland Islands twice, in 1833 and 1834, and during the first visit Darwin discovered fossil shells, mostly brachiopods. His first impression had been unfavourable, but, after that discovery, he noted in his diary: “The whole aspect of the Falkland Islands were however changed to my eyes … for I found a rock abounding with shells; and these of the most interesting age.” Darwin published his account of Falklands’ geology in 1846. The “interesting age” proved to be Devonian and, as more data were acquired, a close and surprising similarity was established with the fauna of equivalent age in South Africa. This similarity was soon extended to other aspects of the Falklands rock succession, while the geology of neighbouring Patagonia proved to be quite different. These relationships were not readily explicable without recourse to continental drift, so were largely ignored for many years, … Read More

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Diadematoid echinoids: A cryptic part of the tropical fossil record

Stephen K Donovan (The Netherlands) The writers of holiday brochures invariably fail to mention, let alone emphasise, the bad points of a location. For example, I’ve lived in both Jamaica and the Netherlands, and, for me, the thing that unites these two countries is the number of mosquitoes. However, as mosquitoes aren’t a good sales point with tourists, they are carefully ignored in holiday brochures and advertisements. Another Caribbean critter that doesn’t get mentioned until you actually arrive and want to go for a dip in the sea is the sea urchin, known in Jamaica as a sea egg. In truth, any danger to the unwary swimmer comes from the few species of regular echinoid that have long, pointed spines. These are found in many shallow water habitats, but are best concealed (and, therefore, most dangerous to the swimmer) in seagrass beds. The best protection from these echinoids is to wear an old pair of training shoes that you’d be happy to dispose of at the end of the vacation. However, without prior knowledge, who would take such a thing on holiday with them? Among these echinoids, the one most likely to ruin your holiday is the black, long-spined urchin, Diadema antillarum (Phillipi) in the Caribbean; which is broadly similar in morphology to the figured specimen, Diadema setosum (Leske) from Indonesia (Fig. 1). These echinoids have relatively small bodies, but numerous long, needle-like spines. These are, essentially, single calcite crystals. The unsuspecting swimmer treading on such an urchin will have … Read More

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Thomas Jefferson’s mammoth problem

James Smith (USA) Author of the Declaration of Independence, creator of the University of Virginia, a Founding Father and third president of the USA, Thomas Jefferson was a pioneer. Of this, you are undoubtedly aware. And, like most pioneers, Jefferson fostered an interest in virtually every aspect of science. This appetite for knowledge propelled him to organise the Lewis and Clark Expedition into the then-uncharted western area of the continent, brought under American governance by the Louisiana Purchase, which took place during his presidency. Considered an expert in civil engineering, anatomy, architecture, anthropology, physics, mechanics, meteorology, navigation, ethnology, botany and geography, it is not surprising that Jefferson was also a pioneer in our own field – palaeontology. “Science is my passion,” Thomas Jefferson wrote, “politics is my duty”. It could almost be said that he was as much of a pioneer in science as in law and politics – indeed, although we may remember his political pursuits as his most historically-resonant, his scientific achievements were pretty admirable. “Nature intended me for the tranquil pursuits of science,” he wrote, “rendering them my supreme delight.” Christopher Hitchens thought that, were Jefferson born a decade later, he would have been one of the finest palaeontologists in history. However, as it was, Jefferson was still looking at mountains and asking how shells got so high up on the mountaintop. The side project of many an eighteenth century American scientist was the study of mysterious teeth, bones and seven-foot tusks yielded by swamps and riverbeds. … Read More

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