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Gobustan Rock Art Cultural Landscape in Azerbaijan

Khursheed Dinshaw (India) Gobustan in Azerbaijan is an interesting site depicting prehistoric rock art. The petroglyphs here vary in age from the Upper Palaeolithic Era to the Middle Ages (Fig. 1). A UNESCO World Heritage Site, more than 6,000 images can be seen here (Figs. 2 to 9). The petroglyphs are carved on three mountains called Beyukdash, Djingirdag and Kichikdash, respectively. Fig. 1. Petroglyphs varying from Upper Palaeolithic Era to the Middle Ages. Fig. 2. Gobustan Rock Art Cultural Landscape. There is also a museum where artefacts that have been excavated are exhibited (Figs. 10 to 14). The museum also provides information about the climate change periodization of Gobustan. About 21,000 years ago, juniper trees grew here. There is also a strong possibility of tugay forests in which wild cherries and pomegranates grew. (Tugay is a form of forest or woodland associated with fluvial and floodplain areas in arid climates.) Wild cherries and pomegranates grow in the region even today. Fig. 3. The UNESCO World Heritage Site of Azerbaijan. Fig. 4. More than 6,000 images can be seen here. Credit for the discovery of the petroglyphs goes to Prof I M Jafarzade. He found them in the 1930s on the Djingirdag Mountain. Fig. 5. Visitors learning about petroglyphs. Fig. 6. Prof I M Jafarzade discovered the images on these rocks. Most of the petroglyphs of Gobustan have been made by engraving an image contour on the rocks. On the Beyukdash Mountain, on rock No 67, there are a total of … Read More

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Book review: Cro-Magnon: The Story of the Last Ice Age People of Europe, by Trenton W Holliday

The Cro-Magnons were a population of early modern humans (that is, they were physically indistinguishable from us, today), who lived in Europe between about 40,000 and 10,000 years ago, during the Upper Palaeolithic period. This information comes from Trenton Holliday’s excellent book, which tells the story of these people in the context of recent scientific advances. However, while it does not shy away from complex scientific issues, the book is written with a light, understandable touch.

Shetland – an archipelago on the edge

Allen Fraser (UK) Shetland is a spectacular group of islands with a varied geology, a wonderful landscape and a special flora and fauna, peopled by a culture distinct within the British Isles. Shetland remains one of Britain’s natural treasures.” (J. Laughton Johnston) Fig. 1. St Ninian’s Isle. The islands Shetland sits on the edge of the European continental shelf and is sinking. Since the end of the last glaciation about 10,000 years ago, relative sea level has risen by about 120m and has fashioned an archipelago of over 100 islands. The island group extends over a distance of 110km from Muckle Flugga (Fig. 2) in the north to Fair Isle in the south, and a convoluted coastline, over 2,700km in length, means that no point on land here is more than 5km from the sea. Fig. 2. Muckle Flugga, a small rocky island north of Unst in the Shetland Islands. The landmasses of the larger islands are generally in the form of roughly north-south ridges of hills forming the ‘spine’ of Shetland. The hills, mainly composed of acidic granite, schists and gneisses, are treeless and are generally covered by peat or blanket bog. The valley floors between the hills of the central Mainland (the largest island) are composed of crystalline limestone and are generally more fertile. Together with sandy coastal areas, they form the best agricultural land. Fig. 3. The fertile valley of Tingwall. Fig. 4. The port of Scalloway, the largest settlement on the west coast of the Mainland, … Read More

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The how and why of Tiger’s eye

Deborah Painter (USA) Tiger’s eye is definitely an unusual semiprecious gem because of a phenomenon called “chatoyancy” seen in only a few minerals and stones. “Chat” is of course the French word for “cat”. The golden bands of polished specimens remind one of a cat’s eye. Chatoyancy refers to the way the distinctive bands of yellow and golden brown within the polished stone refract light as one tilts and moves the stone. It seems to possess an inner dimension. That inner dimensionality effect is due to the fibres of crocidolite asbestos (a variety of magnesio-riebeckite) locked within the stone (Fig. 1). Magnesio-riebeckite is composed of silicon, iron and sodium. Quartz is composed of silicon and oxygen. Quartz has impregnated the greater portion of crocidolite within Tiger’s eye and only a small percentage is crocidolite asbestos. This is why Tiger’s eye is known as one of the “pseudomorphs”, which is a mineral that transforms partly into a different mineral. Fig. 1. This specimen of crocidolite from the Mineralogical Museum in Bonn resembles a shimmering holiday decoration. Its beauty is in sharp contrast to its reputation as asbestos, which is listed as most hazardous to health. (Credits: Raimond Spekking.) A hydrothermal metamorphic process created the pseudomorph known as Tiger’s eye. In a hydrothermal condition during metamorphism of the bedrock in which crocidolite occurs, the mineral will experience tiny fractures. Quartz grows on the outer surface of the crocidolite. This process repeats itself until the crocidolite is surrounded completely in quartz and imbedded … Read More

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Yana’s rock formations in India

Khursheed Dinshaw (India) “Let’s organize a hike to Yana to see its impressive rock formations,” suggested Ramesh V, the wellness consultant at Gamyam Retreat, which is a luxury wellness resort located an hour’s drive from Yana. My interest piqued. The next day, I headed to Yana located in Uttara Kannada district in the state of Karnatake in India. The area is surrounded by the thick forests of the Western Ghats. Fig. 1. Mohini Shikhara is 300 feet (91.5m) in height. After parking the vehicle, my hike began through the forest along the demarcated trail for hikers. Hardly a few minutes had passed before I was rewarded by the spectacular view of a sharp-edged peak. It was made up of hard and compact siliceous limestone of Late Archean age, that is, around 2.65 billion years old. Known as Mohini Shikhara (Fig. 1), this imposing rock sentinel is 300 feet (91.5m) in height. Fig. 2. A rock formation of the Late Archean age. After admiring it for a while, I continued ahead and spotted other rock formations along the way (Figs. 2, 3 and 4). Fig. 3. A rock formation surrounded by the thick forests of the Western Ghats. By this time, the trail had turned into a series of steps with railings for support. I enjoyed the solitude of the forest, the cascading streams and the bird calls everywhere along the way. And there are close to 60 rock formations at Yana, which are scattered throughout the forest. From among those … Read More

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Stones that illustrate themselves

Deborah Painter (USA) Earlier in the month of September 2022, my friend David and I spent an afternoon with a fellow named Ellery, a long-time member of a rock collecting club we joined a year ago. Ellery allowed me to photograph some of his rock and mineral specimens, including a rough piece of ‘wonderstone’ of approximately 30cm in length and 19cm in width, from southern Utah, USA (Fig. 1). Fig. 1. Shinarump Wonderstone is a variety of chalcedony that features swirls and other decorative patterns. (Credits: Deborah Painter; specimen from the collection of Ellery Borow.) The piece contained what looked like a painting of the flanks of a slot canyon one might see in the very area where it is found (Fig. 2). Fig. 2. A slot canyon in Page, Arizona USA, just 180km to 185km from known sources of Shinarump Wonderstone. It reminds one of the ripples and swirls in the Wonderstone in Fig. 1. (Credits: Brigitte Werner, Pixabay.) On the opposite side of the same specimen was a fish’s head, complete with an ‘eye’ (Fig. 3). Fig. 3. This ‘fish head’, complete with a fishy ‘eye’ is the image that greets you when you turn over the Shinarump Wonderstone specimen in Fig. 1. (Credits: Deborah Painter; specimen from the collection of Ellery Borow.) None of the images were artificial or cut in a particular way to bring out these ‘images’. I was instantly reminded of the pietra paesina stones of the Florence area of Italy. The latter have … Read More

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Book review: Minerals of the English Midlands, by Roy E Starkey

Goodness me! This is a massive work (432 pages) – but written with enthusiasm from the heart, with authoritative text, lovely photos throughout, fascinating anecdotes and history, with detailed geological descriptions of all the relevant counties. Now, I’m no expert on minerals, which fall well outside the scope of my interests. However, I cannot praise this book too much.

Book review: Introducing Geomorphology: A Guide to Landforms and Processes (2nd edition), by Adrian Harvey

As I said in my review of the first edition of this guide, I love geomorphology. In fact, I have loved it since my school days and deeply regret not having studied it at university. However, as I said in that review, I suspect many people are discouraged by its scientific name, but all it means is the study of the earth’s landforms and the processes that create the landscapes we see today.

Environmental scientists and geology (Part 3): Geology and soil science in the ‘National Environmental Policy Act document’ process in the USA

Deborah Painter (USA) I am an ecologist and general environmental scientist, specialising in transportation, energy and industrial development planning to minimise deleterious environmental impacts. I live in the United States and have also written several articles for this magazine. I appreciate just how important local geology and soil science are … Read More

Environmental scientists and geology (Part 2): Geology and soil science in the ‘Wetlands and Waters Permitting’ process in the USA

Deborah Painter (USA) I am an ecologist and general environmental scientist specialising in transportation, energy and industrial development planning to minimise deleterious environmental impacts. I live in the United States and have also written several articles for this magazine. One of the things I really appreciate is just how important … Read More

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

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 … Read More

Book review: Trilobites, Dinosaurs and Mammoths: An introduction to the prehistory of the British Isles, by James McKay (for the Palaeontological Association)

This is an interesting little booklet and very much a new departure for the Palaeontological Association. You will be aware that I have reviewed several of its many excellent fossil guides in this magazine. However, this recently published tome is somewhat different.

Book review: Recreating an age of reptiles, by Mark P Witton

I like palaeoart. I recently went to the ‘Dinosaurs of China’ exhibition in Nottingham (reviewed in Issue 51 of this magazine) and bought myself a copy of the Chinese palaeoartist, Zhao Chuang’s ‘The Age of Dinosaurs’ – a veritable picture-fest of up-to-date reconstructions of ancient beasts and plants, complete with fuzzy raptors and other bird-like therapods.

Book review: Measures for Measure: Geology and the Industrial Revolution, by Mike Leeder

I sat down to read this over Christmas and what a good read it turned out to be. The appropriate word is ‘eclectic’ – because Measures for Measure is written for all us with an interest in the industrial history of Great Britain, and its impact on the landscape, economy, social history and culture. It’s a great read as it dots about linking places and ideas together, with the link always being the geology.