Friday 31 January 2014

Landslide - boulder smashes through farm in Italy

iGeology and iGeology3D



For some time the free app iGeology for all smart 'phones has been available. When you have a signal, it's wonderful, as it tells you the geology beneath your feet.
Have you also discovered iGeology 3D? You point your phone at a landscape and the app drapes the geology over the top!
BGS (British Geological Society) tells us that iGeology is now available for Kindle, but maybe only for certain models, e.g. Kindle Fire.

Thursday 23 January 2014

February 6th Naxos - geology explained

On Thursday February 6th, Bath Geological Society begins its 2014 programme with a short AGM followed by 'Naxos - geological evolution of a gneiss dome'
by Dr. Doug Robinson, University of Bristol
Naxos is the largest of the Cyclades islands, which an ancient fable indicates were formed in a "War of the giants", from enormous rocks that were thrown against each other by the Giants and the gods. This talk will explore the actual ~200 million year geological history of the island, which lies in a very active present-day plate tectonic setting. The geology of the island is dominated by a Mesozoic carbonate/detrital succession that has been deformed and metamorphosed in the orogenic collision between the African and Eurasian plates that gave rise to the overall Alpine chain. The metamorphism has converted the carbonate sediments into excellent marbles, which were widely used in building of Delphi and the famous Lion terrace in Delos, while former soils have been turned into the well-known emery deposits of the island.
AGM 7p.m. at BRLSI, 16 Queen Square, Bath
Everyone welcome, visitors £4 - free refreshment.
BGS Building Stone Guides available free - first come, first served.

Dinosaur being delivered to Boston Museum of Science, 1984


Bottle-brush arthropod - Enalikter aphson

A bizarre marine creature that roamed the oceans 425 million years ago has been revealed in unprecedented detail. The strange animal, named Enalikter aphson, was just under an inch (2.4cm) long and had a round head, no eyes and a whip like 'tongue' protruding from its mouth that it used to catch tiny sea creatures. At the end of its body there was a pincer attached to a primitive tail that may have been used as a weapon against predators. The extinct arthropod did not have a hard shell but was remarkably well-preserved after becoming encased in a nodule of minerals that acted, according to scientists, like a womb - preventing the fragile creature's deterioration. This enabled the specimen to be digitally recreated in 3D after researchers painstakingly used an X-ray technique to analyse a series of images pixel by pixel. Dr Derek Siveter, of Oxford University, described the specimen as "the jewel in the crown of palaeontology. In 3D it looks a bit like a tiny bottle brush, or even a Christmas tree. Its body was soft and flexible so it is incredible it has survived. It is beautiful."
Arthropods are a highly diverse family of invertebrates which include insects, arachnids and crustacea. They make up more than 90 per cent of the entire species within the animal kingdom. Enalikter aphson predates any known living arthropod and was discovered in rocks in Herefordshire at a site that has proven to be a treasure trove of fossils. The bizarre animal lived so long ago the UK was south of the Equator at the time. The temperature would have been warm and tropical.

Sunday 19 January 2014

Pangaea

 Map of Pangaea showing current international borders

Saturday 11 January 2014

2013 - The year in volcanic activity

2013 was a particularly eventful year for the world's volcanoes. Out of an estimated 1,500 active volcanoes, 50 or so erupt every year, spewing steam, ash, toxic gases, and lava. In 2013, erupting volcanoes included Italy's Mount Etna, Alaska's Mount Pavlof, Indonesia's Mount Sinabung, Argentina's Volcán Copahue, and a new island emerging off the coast of Nishinoshima, Japan. In Hawaii, the famed Kilauea volcano continued to send lava flowing toward the sea.
Collected here are scenes from the wide variety of volcanic activity on Earth over the past year. [36 photos]

Colour of ancient sea creatures


Oldest evidence for flowering plants

A 100-million-year-old piece of amber from mines in the Hukawng Valley of Myanmar (formerly Burma) has revealed the oldest known evidence of sexual reproduction in a flowering plant. The amber contains 18 tiny flowers of a previously unknown Cretaceous plant genus and species, named Micropetasos burmensis.  The perfectly-preserved scene is part of a portrait created when flowering plants were changing the face of the Earth forever, adding beauty, biodiversity and food. It appears identical to the reproduction process that flowering plants (angiosperms) still use today. The flower cluster is one of the most complete ever found in amber and appeared at a time when many of the flowering plants were still quite small. Even more remarkable is the microscopic image of pollen tubes growing out of two grains of pollen and penetrating the flower’s stigma, the receptive part of the female reproductive system. This sets the stage for fertilization of the egg and would begin the process of seed formation – had the reproductive act been completed.
More information.

Wednesday 8 January 2014

January 12th - Ramble and fossil hunt

Ramble and fossil hunt led by Judy Hible in an area described by William Smith (February 6th Cirencester to Bath ,1803)
This will be a 7.5km walk with 400m of ascent from Cold Ashton, down St Catherine's Valley to Monkswood Reservoir, which provides water for Bath. Up the Limestone Link and on a path cut through Great Oolite with potential for fossil collecting.
Time : approx 2.5 hours (1.5 hours walking).
Please wear stout, waterproof boots with good grip. Some stiles and wet fields.  No need for hard hats. Bring refreshments.
Contact Judy by email or 07765 266908
Park in Cold Ashton and meet near the church, ST 751 727 at 10.30am

January 14th - WEGA and WRGS lectures

WEGA
Tuesday January 14th
Three graduate students presentations:
Chris Rogers - The taphonomy and sedimentology of the Jehol biota
Marit Van Zalinge - Unravelling the ignimbrites of the Oxaya formation,
North Chile

Pete Spooner - Deep-water corals: improving the tool kit for unravelling
past oceanographic change

7.30 Wills Building, University of Bristol - all welcome

WRGS
Tuesday 14th January -
The Origin, Evolution, and Future of a Mud Volcano Disaster in Java
by David Shilston
On 29 May 2006, a new mud volcano erupted adjacent to an exploratory gas well in the Porong District of Java. Colloquially called LUSI (Lumpur Sidoarjo), the mud volcano is unlike naturally occurring mud volcanoes, as it has until recently maintained continuous and high mud flow-rates at high temperatures. Although there is much debate amongst geoscientists about the cause of the mud volcano, it is the social and economic impact that is of greatest importance to the many thousands of people made homeless and to the economy of the area.
David Shilston’s talk will describe LUSI, its evolution, its impact and what can be said about its future development.
6.30 Wills Building, University of Bristol - all welcome

Please note: Arrangements will be made for people to attend all lectures

Tuesday 7 January 2014

Field Geology on the Outer Hebrides & in Northern Scotland

Dr. Nick Chidlaw is currently offering two 1–day courses for next March; these are indoor-based, and describe field areas to which he has run courses in the past. They may be attractive particularly to people who are not in a position to visit these field areas, e.g. insufficient time available because of family / work commitments, or health problems.
Each course would comprise powerpoint-based lectures, together with examination of hand specimens of relevant mineral and rock types, and published geological maps of the field areas. The hand specimens have been collected by the tutor in the field areas described. 
The venue would be in the Buckingham Room (single storey building by the car park) at The Chantry, 52 Castle Street, Thornbury, South Glos. BS35 1HB.  Tel: (01454) 414268. See venue website for further details, including location map. On each course attendees would bring their own packed lunch and other refreshments, or go into the town for lunch.
These two 1–day courses have a fee of £25.00 each. 

If you / anybody else you know, would like to attend either or both of these offered courses, please contact Nick.
Please note: these courses are to run on the same weekend, but are independent of each other; you can enrol on both if you wish to, or one of them, according to your interests / availability.  
The deadline for the minimum number (10) of enrolments is Saturday 8th February (4 weeks before the courses are due to run). Maximum number of attendees 30. If the minimum number for each course is reached by this deadline, the arrangements will be able to continue, if not, the course(s) not reaching viability will be cancelled, and fees received will be returned to those who sent them in, soon after. Enrolments above the minimum numbers for each course will be able to continue for up to 1 week before it is due to run.  

FIELD GEOLOGY ON THE OUTER HEBRIDES
Saturday 8th March. 10.00 am – 5.00 pm
The Outer Hebrides (also known collectively as the ‘Long Island’) off NW Scotland are some 130 miles in length, possess striking landforms, and are underlain mostly by the oldest rocks in the British Isles. This day course will introduce you to these islands, from the largest, Lewis, in the N with its rolling moorlands, through the mountainous Isle of Harris, the diverse country of the Uists and Benbecula, to the rocky island of Barra in the S. The hardness of much of the bedrock, former glacial cover and subsequent marine erosion have created widespread exposures; both coastal and inland. Here are found the most extensive outcrops in the British Isles of the Lewisian Complex, parts of which were formed around 3000 million years ago, over half the age of the earth itself. These rocks have similar characteristics and geological history to parts of northern Canada and Greenland, to which they were once joined. Today, the Lewisian Complex is understood to be composed of a series of distinct crustal units or ‘terranes’, which were formed / progressively amalgamated, through a series of plate tectonic collisions between 3000 – 1500 million years ago. Subsequent erosion has removed great thicknesses of these rocks, so that today we can walk across what formed 10s kms below the crust’s surface in high pressure/high temperature environments: including varieties of gneiss with striking deformation structures. In Permo-Triassic times, around 300 - 200 Million years ago, the British crust was being stretched as the North Atlantic Ocean Basin began to form. Rift basins developed to the E and W of what is now the Outer Hebrides, into which sediments accumulated, under a hot desert climate. Near Stornoway on the Isle of Lewis, occurs an arm of one of these rifts, providing the only place on the Outer Hebrides where these rocks can now be studied on land. 
A handout outlining the day’s programme, and a list of optional suggested reading, will be provided on the course. No prior knowledge of geology or the study area is assumed. 

 FIELD GEOLOGY IN NORTHERN SCOTLAND: THE GRAMPIAN OROGENIC BELT
 Sunday 9th March. 10.00 am – 5.00 pm.
 In late Precambrian times, c. 750 million years ago, northern Scotland was located in the mid latitudes of the S. hemisphere, and was part of a large area of continental crust comprising much of what is now Greenland, N America, Scandinavia and northern S America. Across this continental mass a linear zone of plate tectonic extension was developing, within which lay the crust that is today northern Scotland. The crust that now lies between Scotland’s Great Glen in the N, and the Highland Border in the S, began at this time to stretch, rupture, and episodically subside, and sediments began to be deposited on top. This tectonic setting and accumulation of sediments continued into Early Ordovician times, these strata forming the Dalradian Supergroup, over 25 km (15 miles) thick. The Dalradian Supergroup records a wide range of environments from river plains to deep sea, and are locally interbedded with volcanics and metalliferous ores; some of these strata represent glacial deposits laid down during submarine avalanches. In Mid Ordovician times, a plate tectonic collision event, known as the Grampian Orogeny, affected the Dalradian Supergroup: in some areas there was little deformation and alteration, but in others the rocks underwent intense deformation to form colossal folds and faults, and some were metamorphosed to the point at which they began to melt.
A handout outlining the day’s programme, and a list of optional suggested reading, would be provided on the course. No prior knowledge of geology or the study area is assumed.

Saturday 4 January 2014

Ichthyosaur at Charmouth discovered by former member of Bath GS


The fossilised remains were spotted by hobby collector Alan Saxon, from Chippenham in Wiltshire, who was on a post-Christmas visit to the Jurassic Coast.
The near-complete ichthyosaur discovered after Christmas storms, was hours away from destruction. Storms uncovered the 1.5m (5ft) fossil at the base of Black Ven near Charmouth on Boxing Day. The giant marine reptile fossil was painstakingly removed over eight hours, shortly before another storm was due. Professional fossil hunter, Paul Crossley helped excavate it.
With only part of the snout missing, but with most vertebrae and its rib cage in place, it is one of only a few ichthyosaur fossils found in such a complete condition on the Jurassic Coast in the past decade. Ichthyosaurs (literally 'fish-lizards') were predatory dolphin-like reptiles that swam the world's oceans 200 million years ago, at the time of the dinosaurs.
Read more

Winter storms

We were buying ice-creams here at Caswell Bay on our field trip in October.


More images here.

Earth Heritage Magazine

Our efforts in helping to clear the de la Beche unconformity in Vallis Vale have been reported in the latest Earth Heritage Magazine, no. 41, page 35.
You can download your free copy here.