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The violent story of Cumbria’s ancient volcanoes

Ian Francis and Bruce Yardley (UK) The violent eruption that occurred near the Pacific island of Tonga in January 2022 reminded the world of the ferocious power of volcanoes. The most destructive eruptions can bury huge areas in layers of ash and lava, generate tsunamis, and even alter the Earth’s climate by injecting vast quantities of ash and aerosol droplets high into the atmosphere. Modern Britain is luckily far from any active volcanoes (Vesuvius in Italy, and the volcanoes of Iceland are the nearest to us), but this was not always the case: geological evidence shows that around 455 million years ago, during the Ordovician Period,an intense, but short-lived, periodof volcanic activity took place inwhat is now the Lake District. The geological record of that activity is mainly found in Lakeland’s high and rugged central fells, stretching from Ennerdale and Wasdale in the west, across to Haweswater in the east. Most of the Lake District’s highest fells are found in this central belt, including the Coniston fells, Pillar, Great Gable, Kirk Fell, the Sca Fells, Esk Pike, Crinkle Crags, the Langdales, Helvellyn and High Street (Fig. 1). Fig. 1. Volcanic rocks form the high central fells of the Lake District. The image shows banded volcanic ash beds (tuffs) on the flank of Glaramara, looking east over Heron Crag (in shadow), Ullscarf, and beyond the Helvellyn range. (Photo: Stuart Holmes.) As far back as the early nineteenth century, those familiar with the rocks and landscape of the Lake District (such as … Read More

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The mud volcanoes of Azerbaijan

Khursheed Dinshaw (India) The first time I saw a mud volcano at close range was in Rotorua in New Zealand. I was fascinated – the raw energy of the erupting mud massively appealed to me. Once back home, I read up on mud volcanoes and learnt that, out of the almost 700 present in the world, about 300 of which are located in Azerbaijan and the Caspian Sea. No wonder scientists call Azerbaijan ‘the region of mud volcanoes (Fig. 1). These mud volcanoes reach heights of 200 to 500m and temperatures of 1,000 to 1,2000C. They include active and extinct underwater, island-type and oil producing volcanoes. In Azerbaijan, one can find these natural wonders on the Absheron Peninsula, at Gobustan and the Shirvan plain. Fig. 1. A map of the mud volcanoes of Azerbaijan (© Mark Tingay and Google Earth). Recently, I was fortunate enough to visit the country and booked a tour to Gobustan to experience the famed mud volcanoes, which are locally known as ‘Pilpila’ (Fig. 2). One can drive up to the designated spot in any vehicle, but the last few kilometres necessary to reach the volcanoes is only possible by authorised cars driven by locals who know the landscape like the back of their hand. This is important, because the terrain is barren and there are no marked roads, routes or signposts to get to the mud volcanoes. Fig. 2. Mud volcanoes are called Pilpila in Ajerbaijan. My driver was born and brought up in a … Read More

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That Arizona hot spot might be a volcanic field

Deborah Painter Let’s see, when I say “Arizona hot spots”, what might come to mind for many people are the restaurants, nightclubs and sports events in Phoenix (the US state’s largest city), the Grand Canyon of the Colorado River, attracting visitors from around the world, Tombstone (the infamous “town too tough to die”, where the equally infamous 1881 gunfight at the OK Corral took place), and any portion of the desert in the daytime during August. But how many people think of the many volcanoes in Arizona USA, part of a volcanic field that is likely not finished erupting? Arizona, USA has seven young (Quaternary Period) volcanic fields. The three youngest fields are the San Francisco, Uinkaret and Pinacate volcanic fields. The first two of these young fields are on the Colorado Plateau of northern Arizona; the Pinacate Field is much farther south on the Arizona-Mexico border. The San Francisco Field is the focus of this article. It is situated near Flagstaff and Williams in northern Arizona (Fig. 1). It extends approximately 5,0002km from Williams to the Little Colorado River. There are slightly over 600 cones. The field was active as recently as 932 BP (Before Present), with the eruption that formed Sunset Crater at Sunset Crater Volcano National Monument. Fig. 1. The San Francisco Volcanic Field. (Credits: United States Geological Survey/Wikimedia Commons.) The spectacular San Francisco Peaks within this field are originally a single stratovolcano that experienced deep erosion (Fig. 2). Mount Elden near Flagstaff is a large volcanic … Read More

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Lake District: Landscape and Geology, by Ian Francis, Stuart Holmes and Bruce Yardley

I recently reviewed another of the guides in Crowood Press’s excellent “Landscape and Geology” guides, which was undoubtedly a great read. And this one is equally good, with great, full colour pictures, maps and diagrams, and easy to read text, with descriptions of interesting walks and what can be seen on them.That is, there are easy-to-understand explanations of how the rocks formed and how the geology affects the landscape, and there is also an n exploration of the long human story of the landscapes.

Iceland: Classic Geology in Europe (3rd edition), by Thor Thordarson and Ármann Höskuldsson

reviewed the 2nd edition of this guide a while ago and, as I said then, Iceland seems to set the hearts of certain geologists racing and, reading this field guide and that previous incarnation, it is abundantly clear why. Iceland’s fascinating geology is clearly set out in this concise and authoritative book. The island, astride the Mid-Atlantic Ridge, is a ‘natural laboratory’ where the earth sciences can be watched in real-time. Rifting of the crust, volcanic eruptions and glacial activity are among a host of processes and features that can be observed in this fascinating land.

Book review: Introducing Geophysics, by Peter Styles

Notwithstanding the somewhat daunting use of the word “geophysics” in the title, this is another great book in Dunedin’s Introducing Earth and Environmental Sciences series of guides. In fact, In fact, the only real way to understand the Earth, in all its large and slow-moving immensity, is to study its physics and that means using the classical disciplines of heat, gravity, magnetism, electricity, vibrations and waves. That is, everything we know about the deep Earth has been learnt from geophysics.