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Smilodon family tree

Mike Thorn (UK) In his book, “Architects of Eternity: The New Science of Fossils”, Richard Corfield coins the term “reluctant palaeontologists”. He has in mind those chemists, biochemists and biologists who use the techniques and skills from their own disciplines to shed new light on our ideas about evolution. Ross Barnett, of the Department of Zoology at Oxford, might well be considered to be in this category. A biochemist by training, he has recently co-authored a paper on the DNA of three extinct cats which has helped to lay to rest some of the arguments about the feline family tree. Fig. 1. Smilodon skeleton. Ross came to Oxford in October 2002, to work on a PhD, after completing his biochemistry degree at Edinburgh. His supervisor, Professor Alan Cooper, was interested in cat genetics and had managed to raise funds to carry out research into the relationships of several extinct cats. In particular, there were questions about where the sabre-toothed cats, such as Smilodon and Homotherium, fitted in. Fig. 2. Ross Barnett in his office. As Ross explained: “There has been a lot of study done on these animals. For example, there is a huge collection of thousands of individuals of Smilodon from Rancho Le Brea in Los Angeles, so they’ve been really well characterised from their morphology. “What the palaeontologists had concluded from this was that there was a split at the base of the cat family tree between the group that goes on to form the sabre- tooths – … Read More

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Seeing dramatic folded strata from the car: Sideling Hill, Maryland, USA

Deborah Painter (USA) In many states of the United States and in many locales in the United Kingdom, there are historic markers at the site of an important historic home or event. However, I wonder if every accessible rock formation had its own historic marker, would more people take the time to learn about it? The entire history of the planet is seen in rock formations. Just west of the town of Hancock, in the state of Maryland, USA at Mile Marker 74 on Interstate 68 (coordinates 39° 43’ 11.54” N, 78° 16’ 58.29” W) is the Sideling Hill road cut, a textbook example of tight folds in a mountain (Fig. 1). Until relatively recently, the visitors centre located adjacent to the cut was a perfectly complete historic marker. It gave travellers not only a place to stop to buy refreshments and relax at a picnic table surrounded by shade trees. It also provided an opportunity to read about the history of a spectacular cut in a mountain resulting from a need for safer transportation through a difficult and rugged stretch of road. Fig. 1. View west along Interstate 68 and US Route 40 (National Freeway) from the Victor Cushwa Memorial Bridge as it passes through the Sideling Hill Road Cut in Forest Park, Washington County, Maryland. (Credits: Famartin, Wikimedia Commons.) The centre still helps motorists see a geological formation safely from a walkway and an enclosed bridge. Sideling Hill’s transportation story goes back to the earlier days of road … Read More

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Alluvial gold: A geological model (Part 2)

Philip Dunkerly (UK) In A geological model for the alluvial gold environment (Part 1), the first part of this article, I discussed how alluvial gold is found and suggested a geological model for alluvial gold deposits. (Readers are recommended to have another look at that part to remind them of the model.) In this second part, I now turn to the nature of the gold itself. Fig. 1. Gold bullion bars of 400 troy oz. Fig. 2. Sites from around the world. Gulch gold Gulch gold is the coarsest that exists in any part of a river system. If nuggets (pieces of gold weighing more than 0.1g) are present, they will mostly be found in gulches (narrow ravines), provided suitable traps are present, such as irregular bedrock. In gulch alluvium, the vast majority of the gold will be found on, or in crevices within, the bedrock. Gulch gold is often coarse and angular and may contain silicate debris, especially quartz. As examples, gold from Victoria Gulch on the Klondike was described as “sharply angular”. In the Ballarat gullies, some enormous nuggets were found and Canadian Gully yielded nuggets of 50.4, 34.7 and 31.4kg. At Bendigo, White Horse Gully, a 17.8kg nugget (including some quartz) was found. (Interestingly, of a list of 92 Victorian nuggets, 34 came from localities specifically named “gullies”.) Finally, in the Sierra Nevada of California, most of the gold is from gulches or minor streams close to croppings. Fig. 3. Old hydraulicking operation of terrace gravels, note … Read More

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Alluvial gold: A geological model (Part 1)

Philip Dunkerly (UK) Mankind almost certainly first found gold when a yellow, glint from the bottom of a stream bed attracted the attention of one of our ancestors in pre- historic Africa. Ever since, the allure of gold – its colour, improbable density, malleability and scarceness – meant it has been prized, and great efforts have been made to accumulate it. Most ancient peoples venerated and coveted gold and used it for decoration, and empires used gold as a store of value and a medium of exchange. The Egyptians are known to have used gold as early as about 5000 BC, followed by many others, including the Romans, the Incas, the Spaniards and, of course, the Anglo-Saxon invaders of North America, Africa, Australia and New Zealand. Fig. 1. Spectacular Roman paleogravel workings at Las Medulas, NW Spain, now a World Heritage site. The mouth of one of the tunnels through which water was released from a header tank is visible in the shadow. Fig. 2. Panoramic view of Las Medulas, worked by sluicing using water brought through canals up to 60km long. Though gold was won from hard-rock deposits in ancient times, most gold until perhaps 1900 was won from riverbeds, and was traditionally called alluvial or placer gold. Prospecting for alluvial gold required relatively little equipment and always attracted hardy pioneers willing to forego the comforts of society in the hope of ‘getting rich quick’. The gold they found – if they were lucky – could almost instantly be … Read More

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Check those damaged ‘Megalodon’ teeth

Michael E Howgate (UK) Back in the days when I gave my ‘Doctor Dinosaur’ talks to museums, school groups and ‘gifted children’, I would take with me: a plaster cast of the Baryonyx claw; a beach rolled Iguanodon vertebra; and, star of the show, ‘a fossilised dinosaur poo’ (which, in reality, was an Ichthyosaurus coprolite from Lyme Regis). These were some of my collection of props, which helped engage the children through what might otherwise have been a run-of-the-mill slide presentation. Some of the bits-and-pieces I picked up to pass around among the children were a selection of broken and hence dirt cheap Carcharodon megalodon teeth (Fig. 1). (I use Carcharodon instead of the more correct Carcharocles as it is still in common use. The term ‘Megalodon tooth’ is often used by fossil dealers as a short-hand term.) These stood in for the teeth of every child’s favourite dinosaur, the fearsome Tyrannosaurus rex. I would pass the teeth round and get the children to feel the serrated edge as a prelude to explaining how a serrated blade was better at cutting steak – or even a loaf of bread – than a sharper carving knife. “Only try this at home if you are supervised by both parents” was my health and safety rider at the end of this explanation. Fig. 1. Half of a C. megalodon tooth. A cheap and cheerful stand-in for a T. rex tooth. Carcharodon (now Carcharocles) megalodon, which used to be considered the ancestor of the … Read More

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Philadelphia fossils and ferns

Paul Murdoch and Clay Carkin (USA) Our hectic, 48-hour adventure had its beginning many years ago, courtesy of the WWW. My friend, Clay, a sixth grade science teacher in Freeport, Maine, had originally contacted the Calvert Marine Museum fossil club’s website about purchasing fossils to use in his classroom. Although I live outside of Philadelphia in Pennsylvania, I visit the Calvert County Maryland area quite frequently and have a keen interest in the fossils there. Clay and I chatted a few times, and I subsequently agreed to stop by his school and do a fossil presentation. We also discussed going fossil hunting together. However, our schedules never worked until this year. Clay will tell you that Maine is a poor state to live in, if your passion is fossil collecting. Therefore, he and I planned a 48-hour blitz of the better-known fossil localities within a 100 mile or less radius of my home. My wife and I met Clay and his wife Joye at the airport at noon on Friday and, immediately, Clay and I set off to some fossil-hunting grounds. On Friday, the first and only stop for Clay and me was a trip up I-95 and the New Jersey turnpike to the Cretaceous outcrops of marine fossils in the brooks of Monmouth County, New Jersey. After a short detour due to road construction, we were in the Ramanesson Brook, sifting through the sand and pebbles and finding sharks’ teeth. Clay was a natural, finding a shark’s tooth, Squalicorax … Read More

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On the origins of buffalo wings and chicken fingers by means of unnatural connexion, or the preservation of flavoured races in the struggle for clarity

Carl Mehling (USA) Things aren’t always what they seem. The fluidity of information and the frailties of human memory allow for a lot of corruption. Innocent assumptions are made. Sloppy mistakes take place. Unforeseeable accidents occur. And deliberate subterfuge is always there as an option when these others fail. Throw a little time at them and mis- and disinformation get lithified, entrenching them in the human psyche and culture. Fighting for accuracy is a continuous battle. A wing and a prayer Once almost considered throw-away parts of the bird, chicken wings have soared to unimaginable heights since their transformation into ubiquitous bar food in the 60s. Buffalo wings are so absurdly popular in the US that possibly-calculated rumours often circulate that a wing drought is coming, causing the requisite panic. Sports bars riot over this dearth, prompting half-serious suggestions of breeding chickens with more than the pathetic pair that their lineage has provided. Anything this popular inevitably spawns feuds over priority: Who gets to claim bragging rights for such a powerful, lasting and lucrative phenomenon? Fig. 1. Were the origins of Buffalo Wings in a science pub or a brew pub? This certainly happened with Buffalo wings. I’ll spare you the gory details, but although hard to prove definitively, most have settled on the idea that the Anchor Bar in Buffalo, NY began this tangy trend in 1964. However, as it turns out, it can be demonstrated that the origin of buffalo wings actually happened elsewhere, and in 1962. Or, … Read More

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Baths and batholiths

Deborah Painter (USA) “Look over there!” I exclaimed as I stood on the grounds of a manufacturing plant and stared across the tracks of the Atchison, Topeka and Santa Fe Railroad to the east of the plant. I was pointing at several mountains a few kilometres in the distance. “That mountain is glowing!” Standing alongside me was James, the plant’s maintenance supervisor. “I guess because I’ve seen this for the past 14 years, I don’t even pay attention anymore” was his reply. The mountain was not glowing due to any internal source but because exceptionally light toned granites captured and reflected rays of sun streaming from behind a December cloud cover (Fig. 1). Fig. 1. The mountain glowed in the shaft of light, as the sun peeked from behind a cloud. (Credits: Deborah Painter.) The mountains looked like this for most of that chilly day and the glow shifted from mountain to mountain (Fig. 2). Fig. 2. A remarkable combination of December light and greyish-white toned granites produced this day-long glow in the Bernasconi Hills. (Credits: Deborah Painter.) The granitic mountain cluster was in Perris, a city in Riverside County, California in the USA. I have had the good fortune to visit this county twice recently on two separate and unrelated trips a few years apart. And my friend, Mike Ramsey, had been with me on both trips to this same county. He was with me and a friend late in November when we visited another friend in nearby Moreno … Read More

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Plenty of geological fun at Cornwallis’ Cave

Deborah Painter (USA) Cornwallis’ Cave, a feature along the bluffs overlooking the York River in historic Yorktown, Virginia in the USA, is not a real cave and may not even have sheltered British General Charles Cornwallis during the final weeks of the American War of Independence. The National Park Service, which oversees the feature, has little historical evidence that Cornwallis ever used it as a meeting place or as shelter. He probably used a bunker located elsewhere along the river. It is one of the United States’ best-known man-made ‘caves’ and, though composed of Pliocene epoch coquina – a type of sandstone composed mainly of fossil shells – it is unrelated to actual karst features in the area. This feature is a cultural resource that contains holes carved in the stone cave walls for wooden beams to enable storage of supplies during the later American Civil War and is part of the Colonial National Historical Park encompassing many hectares. The cultural history Cornwallis’ Cave is approximately 12.19m in length. It has been sealed off partially by the National Park Service and one can only enter approximately a meter into the cave and view its interior through a wrought iron gate. Were it not for the historic value of the feature and its proximity to the site of testing of mid-nineteenth century hot air balloon warfare, the ‘cave’ might have been levelled long ago. Thankfully, it has not. It is rich in fictional lore, including its reputation for ghosts. A regular … Read More

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Along the Chain of Craters Road, Big Island, Hawaii: Part 5

Dr Trevor and Chris Watts (UK) This is the last of five articles on the ‘Chain of Craters Road’ on Hawaii’ Big Island. The articles are in the form of a road trip that you can follow if you are lucky enough to go to this wonderful part of the world to see its volcanic scenery. Being a road trip in the USA, distances along the road and by foot are given in yards and miles, while measurements are provided in more European and scientific metric units. Hawaiian pronunciationA word about Hawaiian pronunciation – Hawaiians do not say ‘Morna Ulu’ for the Mauna Ulu volcano. They split most vowels up separately: thus, ‘Mah ooner Oo loo’. Similarly, ‘Kill ow eh uh’, for Kilauea; and, ‘Halley mah oomer oo’, not ‘Halley mow mow’, for Halema‘uma‘u; and, ‘Poo ooh Poo ah I’, for Pu’u Pua’i.3.7 miles: the pahoehoe flow Adjacent to the road, this is a wide-spreading series of flows dating mainly from 1969 to 1974, from Mauna Ulu. In the southern part, the lavas also originate from the smaller volcano of Mauna Loa o Mauna Ulu. These are varied, but mainly formed as thin, smooth sheets. They were often broken up after solidifying by being pushed upwards into low mounds by fresh lava invading beneath them and also by the lava beneath them draining away, causing the thin skin to collapse. The forest that existed here is now seen as tree moulds. These are generally in an excellent, fresh condition, and … Read More

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Along the Chain of Craters Road, Big Island, Hawaii: Part 4

Dr Trevor and Chris Watts (UK) This is the fourth of five articles on the ‘Chain of Craters Road’ on Hawaii’ Big Island. The articles are in the form of a road trip that you can follow if you are lucky enough to go to this wonderful part of the world to see its volcanic scenery. Being a road trip in the USA, distances along the road and by foot are given in yards and miles, while measurements are provided in more European and scientific metric units. Hawaiian pronunciationA word about Hawaiian pronunciation – Hawaiians do not say ‘Morna Ulu’ for the Mauna Ulu volcano. They split most vowels up separately: thus, ‘Mah ooner Oo loo’. Similarly, ‘Kill ow eh uh’, for Kilauea; and, ‘Halley mah oomer oo’, not ‘Halley mow mow’, for Halema‘uma‘u; and, ‘Poo ooh Poo ah I’, for Pu’u Pua’i.3.7 miles: Mauna Ulu A short road to the east finishes in a large car park. The trail continues eastwards through the woodland (Fig. 1) for a few hundred yards until it opens out to a view of the twin peaks of nearby Pu’u Huluhulu and the more distant, and much higher, Mauna Ulu (Fig. 2). Fig. 1. A side trail into the forest close to Mauna Ulu car park. Fig. 2. Where the trail divides left and right. The dark a’a lava spreads across the lighter ash and lapilli flow. The twin peaks form Mount Pu’u Huluhulu; the more distant low rise is the shield volcano, Mauna … Read More

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Along the Chain of Craters Road, Big Island, Hawaii: Part 3

Dr Trevor and Chris Watts (UK) This is the third of five articles on the ‘Chain of Craters Road’ on Hawaii’s Big Island. The articles are in the form of a road trip that you can follow if you are lucky enough to go to this wonderful part of the world to see its volcanic scenery. Being a road trip in the USA, distances along the road and by foot are given in yards and miles, while measurements are provided in more European and scientific metric units. Hawaiian pronunciationA word about Hawaiian pronunciation – Hawaiians do not say ‘Morna Ulu’ for the Mauna Ulu volcano. They split most vowels up separately: thus, ‘Mah ooner Oo loo’. Similarly: ‘Kill ow eh uh’, for Kilauea; and, ‘Halley mah oomer oo’, not ‘Halley mow mow’, for Halema‘uma‘u; and, ‘Poo ooh Poo ah I’, for Pu’u Pua’i.2.6 miles: the Hi’iaka lava field and lava tree forest This is just across the road from the Hi’iaka Crater and is the later (May 1973) lava flow. It is very extensive and is little explored beyond the first 100 yards from the road. Before the eruption, there was a forest here, mainly of ʻŌhiʻa trees, but, on 5 May 1973, a series of fissures opened up and vast amounts of lava gushed forth (Fig. 1). Spreading over several miles, it devasted the forest, filled several former collapse craters, became ponded up at the Koa’e Fault cliff, and flowed away. It drained back almost to the original surface … Read More

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Along the Chain of Craters Road, Big Island, Hawaii: Part 2

Dr Trevor and Chris Watts (UK) This is the second of five articles on the ‘Chain of Craters Road’ on Hawaii’s Big Island. The articles are in the form of a road trip that you can follow if you are lucky enough to go to this wonderful part of the world to see its volcanic scenery. Being a road trip in the USA, distances along the road and by foot are given in yards and miles, while measurements are provided in more European and scientific metric units. Hawaiian pronunciationA word about Hawaiian pronunciation – Hawaiians do not say ‘Morna Ulu’ for the Mauna Ulu volcano. They split most vowels up separately: thus, ‘Mah ooner Oo loo’.Similarly: ‘Kill ow eh uh’, for Kilauea; and, ‘Halley mah oomer oo’, not ‘Halley mow mow’, for Halema‘uma‘u; and, ‘Poo ooh Poo ah i’, for Pu’u Pua’i.Down the Chain of Craters Road 0.3 miles: the July 1974 flow This flow, which was mostly pahoehoe lava, covered several hectares. It came from the nearby cone of Ma’una Ulu, a subsidiary cone of Kilauea. The eruption began in May 1969 and lasted until July 1974. It featured many periods of spectacular fire fountains, including one that reached 300m high on 30 December 1969 (Fig. 1). Fig. 1. Mauna Ula fire fountain 1968. (Source: USGS.) Spreading as far as the sea, it added 94 hectares of new land to Big Island – more than 230 hectares. In addition to spreading across the surface, much lava sank, returning into … Read More

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Along the Chain of Craters Road, Big Island, Hawaii: Part 1

Dr Trevor and Chris Watts (UK) This is the first of five articles on the ‘Chain of Craters Road’ on Hawaii’s Big Island. The articles are in the form of a road trip that you can follow if you are lucky enough to go to this wonderful part of the world to see its volcanic scenery. Being a road trip in the USA, distances along the road and by foot are given in yards and miles, while measurements are provided in more European and scientific metric units. Introduction Kilauea volcano dominates the southeast of Hawaii’s Big Island. At 1,247m high, it is by no means the biggest or highest of Hawaii’s peaks, but it is easily the most active. It doesn’t have a peak. Instead, there is a caldera – a huge, oval-shaped collapse crater that formed 500 years ago in the space of a few days – perhaps a few hours. It now measures about 5km long by 3km wide, and is 165m deep (Fig. 1). Fig. 1. Regional sketch of Kilauea’s caldera and the Chain of Craters Road. Its appearance and dimensions have changed considerably over the years as different parts of the caldera have erupted at different times and in different ways. The most spectacular event in the past century was the 600m-high, fire-fountain episode in 1959, which filled the caldera floor with a lava lake and created the ‘side caldera’ of Kilauea Iki. The main eruptive point now is the fire pit known as Halema‘uma‘u that … Read More

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Timeless trees at Florissant, Colorado

Steven Wade Veatch (USA) The huge petrified redwood stumps near Florissant stretch the limits of my understanding. I’m left with only wonder, like a poem I can’t explain. Under the dominion of a clear blue sky, the afternoon light ricochets off the stone, displaying the myriad beige and brown hues of the fossil stumps. Their stony surfaces contrast with tufts of grass that surround them. The nearby orange-red bark of ponderosa pine and the scent of the forest adds another layer of magic, while silent mats of pine green moss cluster in the shadows. Pale lichens cover some of the stone tree rings. The warm summer air buzzes with insects. Fig. 1. View of the Florissant Fossil Beds National Monument’s iconic “Big Stump”. (Photo by S W Veatch.) For me, the stone trees are a portal where the past joins with the present, and time seems to have stopped. I imagine how it all began 34 million years ago when a cluster of nearby volcanoes, once dormant, erupted. It started with a blast of ash and fiery molten rock shooting out from awakened vents. The air became heavy and dark, as plumes of grey ash hazed eastward towards what would become Florissant. Rainfall mixed with loose sediments on volcanic slopes, forming mud – the colour of morning coffee – that rushed down the slopes of the volcanoes at speeds of up to 145km an hour. Ash rained out of the sky and mixed with the spreading mud. The mud popped … Read More

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Cresson Mine: The untold stories

Benjamin Hayden Elick and Steven Wade Veatch (USA) The Cresson mine (Fig. 1) – situated between Cripple Creek and Victor in Colorado – was established in 1894 (MacKell, 2003). No one is certain who started the mine, but records show that two brothers, insurance agents, J R and Eugene Harbeck from Chicago, were early owners. After a hard night of drinking, they sobered up the next day and learned of their new acquisition (MacKell, 2003). The Cresson Mining and Milling Company was organised a year later, in 1895, to raise capital and operate the mine (Patton and Wolf, 1915). The mine continued operating through several leases with low but steady proceeds. Fig. 1. Early view of the Cresson mine, Cripple Creek, Colorado. Photograph date, circa 1914, courtesy of the Cripple Creek District Museum. The Cresson mine became profitable when Richard Roelofs, a known mining innovator, was hired by the Harbecks as mine manager in 1895. Roelofs wrote in an undated letterhead: “I was a prospector, a leaser, a miner, an assayer and chemist, an underground shift boss, foreman, superintendent and then general manager of one to the greatest of Colorado’s mines” (Roelofs, n.d.). Roelofs (Fig. 2) was a newcomer to Colorado, as many were when the Cripple Creek gold rush ignited in 1891. He moved to Cripple Creek in 1893 with his wife Mabel. They had one child, Richard Jr, who was born on 19 August 1894 in Cripple Creek. Fig. 2. Richard Roelofs, manager of the Cresson mine. Photograph date, 1914, … Read More

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Michigan Puddingstone

Steven Wade Veatch USA) Michigan’s puddingstones are intriguing rocks that look like a glob of pudding stuffed with raisins, nuts and bits of cranberries. These white rocks with small red, brown, purple and black pebbles are not a Michigan product. During the last ice age, they hitched a ride into Michigan on an ice sheet and got off in the southern part of the state when the ice melted. Puddingstones went through several steps in their formation (in what is now part of Ontario, Canada) before they went on their journey to Michigan. First, a network of rapidly flowing streams tumbled red and coffee-brown jasper, funeral-black chert, hematite and quartz in their churning water. Next, the streams deposited the material as sedimentary fill in eroded troughs and as alluvial fans when the streams reduced their velocity, and scattered the colorful pebbles onto mounds of sand (Lowey, 1985; Baumann et al, 2001). Fig. 1. An unpolished puddingstone from Michigan. Some contain trace amounts of gold and diamonds. These rocks are commonly found just after farmers plough their fields in Michigan.  Puddingstones were brought to Michigan by ice age glaciers. (Jo Beckwith specimen. Steven Veatch photograph.) Then, the sand and pebbles hardened beneath the Earth’s surface and, over time, formed sedimentary rocks known as conglomerates (Slawson, 1933). Later, intense heat and pressure metamorphosed the matrix of sand into a light-coloured, coarse-grained, sugary-textured quartzite that tightly held the pebbles (Schaetzl, n.d.). These geological forces formed the puddingstones around 2.3 billion years ago. Today, … Read More

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Fossiliferous Florida

Deborah Painter (USA) Seated on the jet heading south to Florida, I thought of my upcoming field work in the central portion of the state. I also hoped to see some monkeys during my brief stay. I knew they were ‘invasives’ but I still wanted to see them. I had read that, many decades ago, rhesus monkeys were brought in for atmosphere in the Silver Springs area by an entrepreneur named “Colonel” Tooey, who was running a glass bottom tour boat operation named “The Jungle Cruise”. By now, the animals have established a breeding population. I also knew that the Withlacoochee, a river yielding vertebrate fossils from several Cenozoic epochs, was not far from where I would be. Therefore, I had my collecting permit from the state of Florida just in case I had a few hours to spare to look around the riverbanks. Upon arrival at the Orlando International Airport, I became instantly aware that most of the travelling public was going to, or coming back from, Walt Disney World and the Epcot Center. I was headed to a mostly wooded area in western Sumter County to do an ecological survey and wetland delineation on Federal lands, and was glad to leave the crazed traffic of the airport behind me, as my rental car sped toward the setting sun of a late September day in 2019. It did not take long for me to enter the agricultural lands where Brussels sprouts, cassava, pears and ornamental house plants were cultivated, … Read More

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Tunnelling for dinosaurs in the High Arctic

Dr Thomas H Rich (Australia) Fig. 1. Location of the Liscomb Bonebed. (© Thomas Rich.) I have no idea what made me look up at that moment. But, when I did, I saw a flash of light reminiscent of the sun glinting off the wings of a flock of birds abruptly and simultaneously changing direction. However, the light was not from a flock of birds. Rather, it was from thousands of individual, fist-sized lumps of rock, together with lumps of half-frozen mud on the steep slope above me. They were glistening due to a film of meltwater covering them and they were simultaneously starting to roll because the tonnes of rock on which they lay had suddenly started to collapse and plummet down towards me on a journey that would end in the frigid waters just below my feet. At that moment, I was digging into permafrost at the base of the steep slope forming the left bank of the Colville River that flows across the North Slope of Alaska and terminates in the Arctic Ocean about 40km further downstream. (The North Slope is the tundra covered coastal plain in northernmost Alaska bordered on the north by the Arctic Ocean and 250km to the south by the east-west Brooks Range.) Like my companions, my efforts were directed towards recovering ‘polar dinosaurs’, at a locality named the Liscomb Bonebed in honour of the geologist who found it in 1961. Fortunately, the tonnes of mud and claystone that cascaded down the bank … Read More

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Glacial rock flour and the preservation of Greenland fossil fish

Deborah Painter (USA) The island of Greenland is now an independent nation called Kalaallit Nunaat in the language of the native-born people. Almost totally covered in ice, the world’s largest island can be compared to a bowl of ice having a rim of ice-free hills and mountains. The southern tip supports agriculture in the form of small sheep farms and cultivation of kale, strawberries and other crops, mostly for local consumption, but fish and allied products reign, accounting for about 89% of exports. To anyone other than someone who calls this land home, much of Greenland might seem remote and perhaps forbidding. My father, the late Floyd Painter, might have thought the same about the great island before he was a master sergeant stationed there for a year. Yes, it was very cold and dark for part of the year, but conversations with him about his time there revealed that he actually had an interesting time in the land of the Midnight Sun. My late father served in the US Navy and Army before his careers as an archaeologist and marine engineer. When in his early thirties, his Army career took him to Camp Lloyd on Michigan Bay, a part of the North Fork of Sondrestrom Fjord (“Deep Stream Fjord” in Danish). It is located 670 38’ North, 500 43.33’ West, HO Chart 5796. Sondrestrom Fjord now appears on maps as Kangerlussuaq (pronounced “kanger-loo-soo-ack”) and is located along the west-central coast. It is the world’s longest fjord. Camp Lloyd, the … Read More

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Pathway to the past: A miner’s photograph

Steven Wade Veatch (USA) Fig. 1, Robert Plews (32), with two daughters, Elizabeth (4) and Mabel (3) and his wife Janet (25), stand in front of their small home in Elkton, Colorado, one of the towns in the Cripple Creek Mining District. (Photo date circa 1899, from the S W Veatch collection.) This photograph, taken around 1899, shows my ancestors posing at their modest frame home, where they lived one step away from Cripple Creek’s gold rush world of cardplayers, whisky drinkers, and midnight carousers. The scene depicts my great-grandfather (Robert Pickering Plews), my great-grandmother (Janet Plews), and two of their daughters in front of their miner’s cabin, built from pine boards, on a hillside in the newly established mining town of Elkton, Colorado. My great-grandparents were from England. Two years after my great-grandfather married my great-grandmother, he left England – by himself – to build a better life in Cripple Creek’s goldfields for the family that he left behind. Robert Plews was a hope-chaser. He carried his dreams from England across the Atlantic and then 1,700 miles to the Front Range and Cripple Creek. He arrived in the gold mining district in 1897. Victoria was the Queen of England, William McKinley was the US President, and Marconi had sent his first wireless transmission. The Colorado Rockies meant a new chance for him at a place with unlimited opportunities. He went to work at the busy Elkton mine. After my great-grandfather established himself in the mining camp, he sent for … Read More

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geology historical / biographies north america urban, art, anthropology

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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geology north america urban, art, anthropology

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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dinosaurs historical / biographies mining north america palaeontology

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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geology north america

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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