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The first phase of an environmental geology investigation (Environmental scientists and geology: Part 1)

Deborah Painter (USA) I am an ecologist and general environmental scientist living in the USA and specialising in transportation, energy and industrial development planning to minimise deleterious environmental impacts. I have also written several articles for this magazine. As such, I appreciate just how much local geology is a vital consideration in many circumstances and especially during one of my routine responsibilities – undertaking a Phase I Hazardous Materials Site Assessment of an industrial or commercial property in the United States. This is the first of three articles on how I and other environmental scientists apply our knowledge of geology in our day to day work. But what is the purpose of these assessments? Companies such as my employer do these to benefit a person or business desiring a loan from a bank to purchase a property or to pay for upgrades. Cities and counties also contract with environmental companies for Phase I Environmental Site Assessments for properties they own and want to improve, or intend to acquire for resale to private parties. For example, city officials may have their eyes on an old former school and grounds as the future site for a new police station, and want to know how expensive it would be to renovate it as opposed to demolishing it to build a new structure. The assessment is done to satisfy the current American Society of Testing and Materials (ASTM) Standard E 1527-13: Standard Practice for Environmental Site Assessments (2013), and the United States Environmental Protection … Read More

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Geojunkets: a geologist returns to Fairbanks, Alaska (Part 1)

Jesse Garnett White (USA) “It is no measure of health to be well adjusted to a profoundly sick society” Jiddu Krishnamurti My Great Grandfather and his son both gave me some advice at a very young age. “Never trust anyone that won’t look you in the eye when they shake your hand” and “It’s OK to pick up hitchhikers while travelling the road”. These are all positive suggestions that have proved valuable both in the States and abroad. I’ve made a number of interesting decisions in my life. One I never thought I’d make was moving back to Alaska. I’ve told colleagues, dozens of friends, family members and myself, “I’ll never spend another winter in Fairbanks.”. Learning the lesson of ‘never say never’”, while travelling into the past and future simultaneously has been interesting to say the least. When a friend of 26 years heard the news, he said, “You can’t escape Covid-19, Jesse.” I completely blew that off and forged ahead. Since returning to Alaska, I’ve been fortunate to have worked with a lot of good folks, meet new friends, network, and travel around the interior and Alaska Range. I was blessed to work as a contract geologist at an open pit mine in both development and exploration roles, assist mom-and-pop miners with permitting, create an LLC, and work at what I consider the best pizza place in Alaska. Winter temperatures dipped below -50oF and snow depth at the cabin reached four feet in total. At the time of … Read More

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Los Angeles’ fractured and filled landscape: a field trip to the sites

Deborah Painter (US) The Los Angeles Times reported on 5 April 2021 that a magnitude 3.3 earthquake struck around 4:15a.m., followed by a magnitude 4.4 quake 29 minutes later. Several aftershocks followed. Seismologist Lucy Jones of the Lucy Jones Center reported that two quakes were 19.31km deep, with an epicentre around Inglewood, in the Los Angeles Basin. She reported that the movement was thrust, probably not on any mapped fault. Californians scarcely even notice an earthquake of magnitude 3.3 at that depth below the surface. That magnitude on the Richter scale is in the order of a large truck driving rather close by, but probably not intense enough to awaken them from sleep at that hour of the morning while being intense enough to warrant a news item. If one believes television programmes and movies, “The Big One” is going to happen sometime in the near future and part of California is going to slide into the Pacific Ocean and vanish beneath the waves, much like an overloaded barge. The trope of the sinking Golden State gained popularity sometime in the 1960s and should have been thoroughly discredited by now. The film industry helped get this into the general public’s mind and the general public keeps it alive. However, it would be impossible for two reasons: Firstly, tectonics is not going to cause the land to subside as though it were a huge chunk of the crust precariously teetering over the edge of the continent. California is firmly attached to … Read More

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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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A field guide to Barbados (Part 6): Central Barbados

Stephen K Donovan (The Netherlands) Stop 1. Waterford District, near Codrington Agricultural Station (approx. 59º 36’ 8” W 13º 6’ 49” N; Fig. 1) The area considered in the final part of this guide is outlined in A field guide to Barbados (Part 1): Introduction (Donovan & Harper, 2010, fig. 1e) and Fig. 1 in this article. As with other articles in this series, the starting point is Bridgetown. Fig. 1. Locality map showing the positions of Stops 1 to 6 in central Barbados. Only those roads relevant to this excursion are shown (after Donovan & Harper, 2005, fig. 12). This figure should be used in conjunction with the geological map of Poole & Barker (1983) and any tourist road map. Key: abc = ABC Highway; B = Bridgetown; 1 = Waterford district (Stop 1); 2 = Dayrells (Stop 2); 3 = Harrison’s Cave (Stop 3); 4 = Welchman Hall Gully (Stop 4); 5 = Horse Hill (Stop 5); 6 = Hackleton’s Cliff (Stop 6); coastline stippled. From the ABC Highway, turn southwest towards Bridgetown on Highway 3. In the area of the turnoff towards Codrington Agricultural Station (on the right), in the parish of St Michael, examine the road cutting, starting at the southwest corner and walking northeast. This is Stop 6 of Humphrey & Matthews (1986, p. 101), in the Middle Coral Rock, just above the First High Cliff and dated at 194,000 years old. The succession shows a range of reef-related biologically-determined facies (that is, sedimentary rocks … 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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A field guide to Barbados (Part 5): The Scotland District

Stephen K Donovan (The Netherlands) Stop 1. Chalky Mount (approximately 59º 33’ 15” W 13º 13’ 55” N; Fig. 1) The area considered in this part of the guide is outlined in Donovan & Harper (2010, fig. 1d) and Figs. 1 and 2. As with other articles in this series, the starting point is Bridgetown. Those wishing to examine the succession and structure of the Scotland District in considerably more detail than outlined below are referred to Speed (2002). This can be complimented by Patel’s (1995) discussion of the geomorphology. Readers are referred to the glossary in A field guide to Barbados (Part 2): The coastal geology of southeast Barbados Fig. 1 Locality map showing the positions of Stops 1 to 7 in the Scotland District of Barbados (after Donovan & Harper, 2005, fig. 11). Only those roads relevant to this excursion are shown. This figure should be used in conjunction with the geological map of Poole & Barker (1983) and any tourist road map. Key: C = Conset Point; H = Horse Hill; W = Welchman Hall; Stop 1 = Chalky Mount; Stop 2 = Bissex Hill; Stop 3 = Coconut Grove; Stop 4 = exposures on East Coast Road; Stop 5 = oil seep; Stop 6 = Bathsheba; Stop 7 = Bath Cliff; coastline stippled. Fig. 2 Geological map of the Scotland District of Barbados (after Donovan & Harper, 2005, fig. 2; Donovan, 2010, fig. 3; simplified after Speed, 2002, fig. 9). Key: open stipple = basal complex; … 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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A field guide to Barbados (Part 4): Bridgetown and the South Coast

Stephen K Donovan (The Netherlands) The area considered in this part of the guide is outlined in Donovan & Harper (2010, fig. 1C) and Fig. 1 of this article. As in other articles in this series, the starting point is Bridgetown. Fig. 1. Locality map showing the positions of Stops 1 to 5 on or near the south coast of Barbados (after Donovan & Harper, 2005, fig. 8). Only those roads relevant to this excursion are shown. This map should be used in conjunction with the geological map of Poole & Barker (1983) and any tourist road map. Key: A = Grantley Adams International Airport; abc = ABC Highway; C = Six Cross Roads; O = Oistins; 1 = the Barbados Museum, Bridgetown (Stop 1); 2 = South Point Lighthouse (Stop 2); 3 = Foul Bay (Stop 3); 4 = Woodbourne Oilfield (Stop 4); 5 = Chapel Quarry (Stop 5); coastline stippled. Stop 1: The Barbados Museum The Barbados Museum and Historical Society was founded in 1933. Its museum occupies St Ann’s Garrison, a nineteenth century British military prison. It is situated in the parish of St Michael, southeast of the central part of Bridgetown, behind the Garrison Savannah racetrack. The museum has displays covering many aspects of Barbadian history and life, including natural history, prehistory and maps. The library is an important research resource, containing 5,000 books, monographs and articles on the culture and natural history of the island. Articles about the island’s natural history, culture and history are … Read More

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A field guide to Barbados (Part 3): Northern Barbados

Stephen K Donovan (The Netherlands) Stop 1: Arawak Cement Quarry The area considered in this part of the guide is outlined in Donovan & Harper (2010, Fig. 1b) and Fig. 1. As with other articles in this series, the starting point is Bridgetown. Drive north from the Bridgetown area on Highway 1, the main west (or leeward) coast road, which is constructed on the Lower Coral Rock and overlies superficial deposits. Fig. 1. Locality map showing the positions of Stops 1 to 4 in northern Barbados (after Donovan & Harper, 2005, fig. 7). Only those roads relevant to this excursion are indicated (including the track to Stop 4). This map should be used in conjunction with the geological map of Poole & Barker (1983) and any tourist road map. Key: C = Content; Ch = Checker Hall; G = Greenidge; T = Trents; 1 = Arawak Cement Quarry (Stop 1); 2 = Animal Flower Cave, North Point (Stop 2); 3 = limestone cliffs west of North Point (Stop 3); 4 = Cluff’s Bay (Stop 4); coastline stippled. The First High Cliff and the Middle Coral Rock are close by in the east (Speed & Cheng, 2004). This coast has been developed for tourism and has neither the magnificent sea cliffs of the east coast, nor the impressive Atlantic breakers seen in the previous excursion. To the west, two submerged barrier reefs, at 22m and 70m water depth, are separated from the coast by a submerged wave cut terrace (MacIntyre, 1967). … Read More

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A field guide to Barbados (Part 2): The coastal geology of southeast Barbados

Stephen K Donovan (The Netherlands) and David AT Harper (Denmark) Introduction This article is the second part of a field guide to Barbados, the first part of which is A field guide to Barbados (Part 1): Introduction. The areas visited by different the excursions outlined in Parts 2 to 6 of this guide are shown in Fig. 1. All itineraries commence from the Bridgetown area and the itinerary outlined in this part is rewritten after Donovan and Harper (2002). The words in italics and bold appear in the glossary at the end of the Part 1. Fig. 1. Relative positions of field excursions described in this field guide (after Donovan & Harper, 2005, fig. 5). (a) Southeast Barbados (Part 2). (b) North Barbados (Part 3). (c) South Barbados (Part 4). (d) Scotland District (Part 5). (e) Central Barbados (Part 6). Charles Taylor Trechmann DSc, FGS (1885-1964) (Fig. 2) was an anachronism, a twentieth century gentleman geologist and archaeologist. He was an amateur with sufficient private means to dedicate his time and use his scientific abilities to make an original contribution to his chosen field of study, an original thinker with a desire to use his observations to interpret broad geological phenomena. He devoted his time to research on Malta, Gibraltar, New Zealand and, particularly, northeast England and the Caribbean. He published over 80 monographs and research papers on geology and archaeology, including at least 40 on the Caribbean (Donovan, 2003, 2008, 2010a). Fig. 2. Charles Taylor Trechmann, DSc, FGS (1884-1964) … Read More

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A field guide to Barbados (Part 1): Introduction

Stephen K Donovan (The Netherlands) This is the first of six articles that will introduce the geology of the Antillean island of Barbados. It is an expanded and more detailed guide derived from two earlier publications (Donovan & Harper, 2005, 2009). The structure of the guide will include a summary of the geology of the island (in this part) and five, one-day field excursions for the geologically-biased tourist. These excursions will introduce the stratigraphy, structure and geological history of Barbados (Figs. 1 and 2), a small Antillean island shaped like a contorted teardrop, about 34km long by 24km at its widest. Fig. 1. The principal features of the geological history of Barbados summarised in a single section at Spring Bay, parish of St. Phillip, on the southeast coast. Professor David Harper (University of Copenhagen) is looking northwest, towards Ragged Point (Fig. 2) and admiring the angular unconformity between the allochthonous Palaeogene basal complex (=Scotland Beds) and the overlying autochthonous bedded limestones of the Pleistocene Coral Rock. A visitor to the island, who wants to undertake fieldwork, should hire a car. The only other reliable forms of transport are bus and taxi. While cheap, buses tend to stick to the main routes, particularly in the countryside. However, the size of the island means that localities are rarely more than a few kilometres from a bus stop. If money is no object, a taxi driver will be happy to drop you at a site in the morning and collect you at a … 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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From the wet clays of Peterborough to the sunny Caatinga of Brazil

David M Martill (UK) After several gruelling years of working in the sticky wet Jurassic clay pits of the Peterborough district for their gigantic marine reptiles and even more massive fishes, it was a refreshing change to fly south and investigate the sun-baked Caatinga of South America. The Chapada do Araripe, on the borders of the Brazilian states of Ceará, Pernambuco and Piaui, had always fascinated me (Fig. 1). Fig. 1a (left). A map showing the location of the Chapada do Araripe in the northeast of Brazil. Fig. 1b (above). Detail of the Chapada do Araripe. This is one of the most important sites in the world for Cretaceous Gondwanan fossil fauna and flora. I had seen specimens of the fabulous fossil fishes (I hope you like the alliteration) in limestone concretions (Fig. 2) that kept turning up in European fossil shops, but what had really caught my eye was a short letter to the scientific journal Nature that described fossil ostracods from those very same concretion horizons. Fig. 2. A typical concretion from the Santana Formation, with a not so typical fish. This is one of the rare fossil rays. I am not an aficionado of ostracods: who is? They mostly look like small baked beans, and it is so tedious trying to mount them on stubs so that you can see them under the electron microscope. No, it was the remarkable quality of their preservation that caught my eye. The specimens in question were described by Ray Bate, … 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 … 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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Palaeontology and caves in Jamaica

Stephen K Donovan (The Netherlands). Although it has a rock record that only extends back to the Early Cretaceous, the geology of Jamaica is sufficiently diverse to satisfy most appetites (Donovan & Jackson, 2012a, b). It lies within the North Caribbean Plate Boundary Zone and displays a range of geological structures, commonly faults, both ancient and modern. There are about 25 Cretaceous inliers, from small to large, each including a sequence of volcanic and/or sedimentary rocks that are rarely metamorphosed. The half-graben Wagwater Belt in the east, flanking the western margin of the Blue Mountain inlier, is a Paleogene succession of terrestrial red beds, shallow to deep water siliciclastics and volcanics. These older rocks are draped by thick sequences of Eocene and younger rocks, which are mainly sedimentary (Robinson, 1994). Of the sedimentary rocks, limestones from the Cretaceous to the Quaternary are particularly widespread (Fig. 1), covering about two-thirds of the island’s surface. Although only subaerially exposed for about the last ten million years, these limestones have been strongly karstified under conditions of tropical high temperatures and seasonal extreme precipitation (Donovan, 2002). This has produced widespread, and magnificent, karst topography. Fig. 1. Simplified geological map of Jamaica, showing the principal stratigraphical units (after Donovan, 1993, fig. 1). Key: B=Blue Mountain inlier; C=Central inlier. Stratigraphy of principal Cenozoic units: granodiorite=Upper Cretaceous to Paleocene; Wagwater Formation, Newcastle Volcanics=Paleocene; Richmond Formation=Paleocene to Lower Eocene; Yellow Limestone Group=Lower to Middle Eocene; White Limestone Group=Middle Eocene to Upper Miocene; Coastal Group=Upper Miocene to Quaternary; alluvium=Quaternary. … 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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