Monday, 30 January 2017

Earthquakes in time

Animations (with Music) of When and Where Earthquakes Occurred


HERE are all the earthquakes between 1st January 2001 and 31st December 2015.

And HERE are the largest Earthquakes since 1900.

The music is not (in my opinion) all that great but the animations are great!

Saturday, 28 January 2017

Next Week Monday 30th January to Sunday 5th February


NEXT WEEKS EVENTS

30th January to Sunday 5th February 2017


The following is an extract from Bristol Geology Calendar

More details can be found in the Calendar and on the web sites of the relevant Society or organisation.


Monday



Tuesday

19:00
 DIGS Meeting
WhenTue, 31 January, 19:00 – 20:00
WhereDWT HQ Forston, Dorchester (map)
DescriptionMeeting at DWT HQ Forston, Dorchester.

Wednesday



Thursday

19:15
 Bath Geol Soc AGM and Lecture - Greenhouse to Icehouse
WhenThu, 2 February, 19:15 – 20:45
WhereBath Royal Literary and Scientific Institution, 16 Queen Square, Bath (map)
DescriptionGreenhouse to Icehouse: reconstructing temperature change during the Eocene Dr. Gordon N. Inglis, Postdoctoral Research Associate, Organic Geochemistry Unit, School of Chemistry, The Cabot Institute, University of Bristol Throughout the Phanerozoic, and possibly throughout geological time, the Earth’s climate has oscillated between greenhouse and icehouse climate states. The most recent transition, from a greenhouse to an icehouse climate state, occurred during the Eocene-Oligocene transition. However, it remains unclear whether CO2 drawdown or some other factors were responsible for long-term cooling during the Eocene (56 to 34 Ma). In order to determine the primary driving mechanisms responsible, we compile and generate new records of marine and terrestrial temperature change during the Eocene epoch using a biomarker approach. Proxy estimates are compared to modeling simulations spanning each stage of the Eocene to help better constrain the drivers of long-term cooling during this time interval. Our results indicate that terrestrial and marine settings were characterized by a long-term temperature maximum during the early Eocene. During the middle and late Eocene, there is a gradual decline in marine temperatures, especially at high-latitudes. The magnitude of cooling indicated by TEX86 is not supported by fixed-CO2 HadCM3L model simulations and provides indirect evidence that drawdown of CO2 (or some, as of yet unidentified, other factor(s)) was the primary forcing for long-term surface water cooling during the Eocene. This hypothesis is consistent with a new high-fidelity record of CO2 concentrations which constrains the relative decline in CO2 concentration through the Eocene to about fifty per cent (from ~1400 to ~770ppm).
19:30
 Dave Green's microscope course
WhenThu, 2 February, 19:30 – 21:30
WhereThe Chantry, Thornbury. (map)
DescriptionRocks and Minerals under the Microscope.  This 10 week course aims to introduce you to the identification and description of rocks and their component minerals under the petrological microscope. This is a practical course, each participant will be provided with a microscope and a set of thin sections of rocks, and will work through a course at their own pace. Held at The Chantry, Thornbury. First meeting 7.30 – 9.30, Thurs 12th January until March 23rd (not Thurs 16th Feb) in the Buckingham Room. Max. numbers 20, “first come, first served” due to number of slide sets. Cost £75

Friday



Saturday

10:00
 Teme Valley Geol Soc - GeolLab
WhenSat, 4 February, 10:00 – 11:00
WhereMartley Memorial Hall B4197 by Sports Ground (map)
DescriptionGEOLAB 4th February 2017 at Martley Memorial Hall 10am For all those, young and old, who have never dared to enrol in a class on the mysterious subject of geology, this day is for you! A morning session in the classroom learning under expert tuition simple facts about the rocks that surround us. After a bring your own lunch, an afternoon in the field examining real rocks and how they shape the landscape. A moderate charge applies of £10 for adults, free to anyone in full time education. This will be a really worthwhile day that will enhance your understanding of the world around you and ad a whole layer of interest to future countryside exploration. Register your interest with me, John Nicklin, 01886 888318 or email martleypfo@gmail.com.

Sunday

Friday, 27 January 2017

Old Faithful WebCam

Live Video of Old Faithful


While writing up my trip to the North West USA with WEGA last summer, I came across this web page which shows what Old Faithful Geyser in Yellowstone National Park is doing now. The quality of the video is very good (especially if you watch in daylight hours!)

My write up is taking considerably longer than the trip but I hope to get beyond the Yellowstone pages soon and onwards to the Rockies!


Here is my photo of Old Faithful doing its thing

Monday, 23 January 2017

Set in stone

Fossilised Sunspots



The Economist reports on a study looking at tree rings in Permian fossilised trees and finding evidence of sunspot activity.

Articles on the Economist web site tend to disappear with time (unlike petrified tree rings) so I have uploaded it to the blog and you can read it below.


An ancient forest reveals the sun’s behaviour 290m years ago


The sunspot cycle was little different then from what it is now



EVERY 11 years or so, a new sunspot cycle begins. Sunspots are apparent blemishes in the sun’s photosphere, the layer which emits its light. Though still hot (about 3,500°C), they are cooler than their surroundings (about 5,500°C) and thus appear dark by contrast. A cycle starts with spots appearing at mid-latitudes in both northern and southern hemispheres. Over time, the spot-generating areas migrate towards the equator. As they do so, the amount of light and other radiation the sun emits first increases to a maximum and then decreases to a minimum, until the spots vanish and the cycle renews.

On Earth, the increased illumination of solar maxima drives photosynthesis, and thus plant growth. That permits botanists to use trees’ annual growth rings to work out what sunspot activity was like hundreds, and occasionally thousands, of years ago. Determining solar activity millions of years ago, though, has not been so easy. But it is of interest to solar physicists, who wonder how far back into the past the oscillations of the sun’s magnetic field that drive the cycle go, and how they might have changed over the course of time.

Now, Ludwig Luthardt and Ronny Rössler of the Natural History Museum of Chemnitz, in Germany, have cracked the problem. They have been able to apply the tree-ring method to petrified trunks from a nearby fossil forest. This forest (imagined in an artist’s impression above) was buried by a volcanic eruption 290m years ago, during the Permian period. And, as they report in Geology, Mr Luthardt and Dr Rössler have found that the sunspot cycle was little different then from what it is now.
The Chemnitz fossil trees, mostly conifers and ferns, are particularly well preserved. Volcanic minerals seeped into them soon after the eruption and petrified them before bacteria and fungi could rot their tissues away. Mr Luthardt and Dr Rössler selected 43 of the largest specimens and looked at their growth rings.

They found 1,917 rings which were in a good enough state to be measured under a microscope. They knew that the trees had died simultaneously, giving them a baseline to work from, and so were able to compare the rings from different plants. They were stunned by how clearly they could see the cycles.

About three-quarters of their specimens showed synchronous growth peaks like those caused by modern sunspot activity. In total, the rings they measured let them study 79 years of forest growth before the eruption. During this period, the solar cycle averaged 10.6 years. That compares with 11.2 years in the modern era, although this figure conceals wide variation in the lengths of individual cycles. Within statistical limits, then, it seems that the sunspot cycle was the same in the early Permian as it is now, suggesting that the sun’s magnetic oscillations were the same then as they are at present. Whether that is a coincidence has yet to be determined, but there is no reason why the method Mr Luthardt and Dr Rössler have developed should not be applied to other petrified forests, from different periods, to find out.

Assynt Geology

A North-West Highlands Geology Video


Bruce Buswell has brought THIS video to my attention. Its rather good! It promotes the North West Highlands Geopark.

Saturday, 21 January 2017

Next Week Monday 23rd to Sunday 29th January

NEXT WEEKS EVENTS

23rd January to 29th January 2017


The following is an extract from Bristol Geology CalendarMore details can be found in the Calendar and on the web sites of the relevant Society or organisation.



Monday



Tuesday



Wednesday

19:30
 Bristol Nats Geology AGM
WhenWed, 25 January, 19:30 – 21:00
WhereS H Reynolds lecture Theatre, Wills Memorial Building, University of Bristol, BS8 1RJ (map)
DescriptionThe Geology Section’s Annual General meeting will consider the report on Section activities during 2016 and appoint the officers and committee to serve for 2017. It will be followed by presentations or short talks by members of the Section. It is hoped that this will include an account of the findings from the recent excavation at Welton Hill near Paulton.

Thursday

19:30
 Dave Green's microscope course
WhenThu, 26 January, 19:30 – 21:30
WhereThe Chantry, Thornbury. (map)
DescriptionRocks and Minerals under the Microscope.  This 10 week course aims to introduce you to the identification and description of rocks and their component minerals under the petrological microscope. This is a practical course, each participant will be provided with a microscope and a set of thin sections of rocks, and will work through a course at their own pace. Held at The Chantry, Thornbury. First meeting 7.30 – 9.30, Thurs 12th January until March 23rd (not Thurs 16th Feb) in the Buckingham Room. Max. numbers 20, “first come, first served” due to number of slide sets. Cost £75

Friday



Saturday



Sunday

O.U. Geol Soc South West Branch Geoweekend and AGM - Field Trip
WhenSunday, 29 Jan 2017
WhereField-trip – location to be confirmed (map)
DescriptionField-trip – location to be confirmed, but plans are afoot to have a leader from Exeter University, Tremough Campus. (In case of bad weather, the field-trip may be shortened or cancelled) For more information contact Trevor by email: trevorlockwood25@gmail.com

Non Uniformitarianism in Geology and Politics

How Geology Won the Election for Trump


HERE is a very interesting YouTube video showing how geology gave the recent election to Donald Trump. And he gives a good account of various aspects of geology too! His YouTube channel looks quite interesting too!

I have a personal interest in this video because a picture he uses is MINE!!! At about 4 minutes 36 seconds is a picture of mine which has, with my permission, got onto Wikipaedia and which he makes good use of.

Banded Iron Formation, in Dales Gorge, Karajini National Park, Western Australia

Saturday, 14 January 2017

Next Week Monday 16th to Sunday 22nd January

NEXT WEEKS EVENTS

16th January to 22nd January 2017

The following is an extract from Bristol Geology Calendar

More details can be found in the Calendar and on the web sites of the relevant Society or organisation.

Monday

Teme Valley Geol Soc - Lecture
WhenMonday, 16 Jan 2017
WhereMartley Memorial Hall B4197 by Sports Ground (map)
DescriptionThe Anthropocene with Professor Ian Fairchild Contact Janet 01886 821061 Mem £1 Non £3

Tuesday

18:30
 Geological Society - Western Region
WhenTue, 17 January, 18:30 – 19:30
WhereTBC (map)
DescriptionRedcliffe Caves Tour

Wednesday



Thursday

19:30
 Dave Green's microscope course
WhenThu, 19 January, 19:30 – 21:30
WhereThe Chantry, Thornbury. (map)
DescriptionRocks and Minerals under the Microscope.  This 10 week course aims to introduce you to the identification and description of rocks and their component minerals under the petrological microscope. This is a practical course, each participant will be provided with a microscope and a set of thin sections of rocks, and will work through a course at their own pace. Held at The Chantry, Thornbury. First meeting 7.30 – 9.30, Thurs 12th January until March 23rd (not Thurs 16th Feb) in the Buckingham Room. Max. numbers 20, “first come, first served” due to number of slide sets. Cost £75


19:30
 Bath Geol Soc AGM
WhenThu, 19 January, 19:30 – 20:30
Where16 Queen Square, Bath (map)
DescriptionAnnual General Meeting 2017


19:30
 Thornbury Geology Group meeting
WhenThu, 19 January, 19:30 – 20:30
Description Thornbury Geology Group, The Chantry, Thornbury, 7.30pm, contact 01454 416882 The group is is an offshoot of Thornbury and District Museum and we welcome new members. Previous geological knowledge can be helpful but is not necessary as members are very willing to share their own knowledge with anyone keen to learn more about Earth Science. The group is loosely following a pre-recorded lecture series which is supplemented by use of other material and geological specimens. On occasions a guest speaker will talk on their specialist topic. Costs are met from attending members' monthly contributions and the group does not have membership subscriptions or a committee

Friday



Saturday

11:00
 South Wales Geologists' Association
WhenSat, 21 January, 11:00 – 12:00
WhereLectures at University of Wales Swansea are held in the department of Geography in the Wallace building. We meet on the landing area inside the main entrance to the building for refreshments with lectures in the main lecture theatre. (map)
DescriptionSaturday 21st January: (Swansea) Volcanic ash and rapid climate change, piecing together the past. Professor Siwan Davies (Swansea)

Sunday

Thursday, 12 January 2017

Early Scottish Fossil

Tetrapod Evolution

An informed source has told me of a very interesting, and well written, article in the Guardian about fossil finds in Scotland. You can find it HERE.


Aytonerpeton microps, also known as “Tiny”. A fossil from the Early Carboniferous of Scotland. The rock was CT scanned and the head printed at twice "life" size. It is still in the rock!

Tuesday, 10 January 2017

Courses by Dave Green

Dave Green's Programme


It can be a little difficult to navigate Dave's website so the following slipped my notice until it was brought to my attention. The original can be found HERE.

Contact details for Dave are:-
Email Dave Green, dave@geostudies.freeserve.co.uk 

Rocks and Minerals under the Microscope. 

This 10 week course aims to introduce you to the identification and description of rocks and their component minerals under the petrological microscope. This is a practical course, each participant will be provided with a microscope and a set of thin sections of rocks, and will work through a course at their own pace. Held at The Chantry, Thornbury. First meeting 7.30 – 9.30, Thurs 12th January until March 23rd (not Thurs 16th Feb) in the Buckingham Room. Max. numbers 20, “first come, first served” due to number of slide sets. Cost £75


Tuesday evenings in the summer: Field Course: Tues 6th June - Tues 18th July June 2017 Geology and Landscape in Gloucestershire (evening field course Tuesdays 7-9 First meeting point:- Haresfield Beacon: Meet at the roadside pull-in just before the steep descent towards Haresfield village GR SO 824 090 . Further sessions on website, separate leaflet, and/or by contacting Dave Green.


Field Course February 2017 : probably a bit late for this but.... 
The Geology of Northern Sardinia Dates will be for a week to 10 days trip around a period from Fri 10th to Monday 20th . The two terranes making up Sardinia were separate parts of Gondwana during most of the Palaeozoic. They participated in the continental collisions at the start and end of the Carboniferous to produce the Variscan Orogenic Belt, across which it provides a classic cross-section showing different styles of folding and faulting, and different grades of metamorphism, together with the intrusion of vast volumes of granite. Following a long period of erosion it became a carbonate shelf environment during the Jurassic and Cretaceous. During the Tertiary and Quaternary, subduction of Tethys oceanic crust produced extensive volcanic activity. LET ME KNOW BEFORE CHRISTMAS IF YOU WANT TO COME to take advantage of cheaper air fares 

The Geology of the Oceans past and present (including plate tectonics, environments, and current/developing ideas on oceanography and marine geology). Often termed the last frontier to be explored on Earth, there have been great advances in our understanding of the oceanic realm over the past half century. This course aims to study the main developments and what we might expect in the future, based on current research. Monday 24th April, for 10 weeks, until 10th July (not 1st nor 29th May). Held at Wynstones School, Stroud Road, Whaddon, Gloucester from 7.30-9.30pm on Mondays. Cost £70. 

Friday, 6 January 2017

Next Week Saturday 7th to Sunday 15th January 2017

NEXT WEEKS EVENTS

7th January to 15th January 2017



The following is an extract from Bristol Geology Calendar

More details can be found in the Calendar and on the web sites of the relevant Society or organisation.


Saturday

South Wales Geologists' Association
WhenSat, 7 January, 11:00 – 16:00
WhereSaturday 7th January 2017: (Cardiff) Holiday Geology – 11:00 to 16:00 (map)
DescriptionSaturday 7th January 2017: (Cardiff) Holiday Geology – 11:00 to 16:00


Sunday



Monday



Tuesday


WEGA Lecture
WhenTue, 10 January, 19:30 – 20:30
WhereEarth Sciences Lecture Theatre, Wills Memorial Building, Park Street, Bristol (map)
DescriptionDr. Frances Cooper, Copper Porphyry deposits in Chile Tectonics, Climate, and Copper in the Central Andes The Atacama Desert, on the western side of the Central Andes in northern Chile is one of the driest places on Earth and is thought to have been dry since at least the middle Miocene. The region is also notable for its abundance of giant copper deposits, many of which have been enriched by the interaction with groundwater when the climate was wetter. It has been suggested that the onset of aridity in the region was caused by uplift of the Andes, which blocked moisture travelling from the east. However, others have suggested that the arid climate could have been established much earlier, long before Andean uplift. In my talk, I will explore the relationship between Andean uplift, aridity, and the end of copper enrichment in northern Chile, which is important not only for our understanding of tectonic and climatic processes, but also for mining company exploration strategies, and where they might seek to find the next “big one”.

Wednesday



Thursday



Friday



Saturday



Sunday


Courses by Nick Chidlaw

March 2017 – Two one-day courses – Scotland and Wales

Nick Chidlaw is offering two 1-day courses in March, using a format that has pleasingly attracted many attendees on previous occasions. These courses are indoor-based, and describe field areas to which Nick has run field courses in the past. One of them describes the striking geology and landforms of the north-west of the Scottish mainland between Durness and Skye, the other focuses on the deposition and subsequent deformation of the Late Carboniferous coal-bearing strata in the main south Wales coalfield. Coal seams and adjacent strata are rarely exposed, but are described here from extensive opencasts . The courses may be attractive particularly to people who are not in a position to visit field locations, e.g. insufficient time available because of family / work commitments, health problems, or may be interested in the opportunity to study lithologies from exposures that are no longer accessible / extant. 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 is the Buckingham Room (single storey building by the car park) at The Chantry, 52 Castle Street,Thornbury, South Glos. BS351HB. 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 / anyone else you know would like to attend either or both of these offered courses please contact Nick Chidlaw   
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 either one of them, according to your interests / availability.
The deadline for the minimum number (10) of enrolments is Saturday 4th February (4 weeks before the courses are due to run). Maximum number of attendees on each course 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 have sent them in, soon after. Enrolments above the minimum number for each course will be able to continue up to 1 week before it is due to run.

Field Geology in North West Scotland

Saturday 4th March 10.00 am – 5.00 pm


This course focuses on the bedrock geology of the mainland of north-west Scotland; the area includes the oldest rocks in the British Isles and some of the oldest exposed on the surface of the earth. The youngest are of Early Ordovician age, but these crop out over a relatively small area, and the majority of the rocks seen are of Precambrian age. Huge (and frankly unimaginable) lengths of time are represented. It is undoubtedly the most complex geology in the British Isles, but also the most striking and fascinating. The landforms associated with this geology are impressive: particularly notable is the almost treeless ice-scoured plateau of the coastal fringe, studded with small lochs and intervening rounded hillocks, and the isolated fin-like mountains rising up from this a few miles inland. It is a very different place from anywhere else in the British Isles.
A key feature of north west Scottish geology is that a major part of it developed when the earth was a radically different planet to that seen today. This includes the stability of the crust (more fluid), allowing magmatic activity and deformation to be more extensive; also the composition of the atmosphere (carbon dioxide rich with little oxygen) allowing different sedimentary rocks to form e.g.. Banded Iron Formations (BIF’s). Another key feature of the geology is its provenance, which belongs to that of Canada, Greenland and northern Scandinavia (all of which were at one time joined together) rather than much of the rest of the British Isles. Along the entire eastern margin of the study area is an enormous and impressive complex of stacked thrust sheets containing associated rocks such as mylonites, which developed during the Caledonian mountain-building in Silurian times, and known as the Moine Thrust Zone.        
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 are is assumed.

Late Carboniferous Coal-bearing strata in south Wales: natural exposures, quarries and opencast mines 

Sunday 5th March 10.00 am – 5.00 pm


During the Carboniferous period (359 – 299 million years ago) conditions became established for the first time for coal deposition to occur on a global scale. Coal-bearing strata were laid down in a variety of latitudes and under a variety of climates: in the northern hemisphere mostly during Carboniferous times, and in the southern hemisphere mostly in the following Permian period ( 299 - 252 million years ago). This has left a legacy of major coal deposits distributed widely across our present continents. Although land plants had evolved to form the first forests during the preceding Devonian period, it was during the Carboniferous period when they became widely distributed on earth; this, coupled with the persistent development of mires across extensive areas, allowed peat deposits to form time and again, during burial these converted to coal.
Our understanding of the deposition of coal-bearing strata has been hugely increased by the mining of coal as an energy resource, particularly from the beginnings of the Industrial Revolution in Britain and Europe in the 18th century. Britain has an abundance of coal-bearing strata, and this was extensively mined until alternative resources of energy and economic globalisation increased from the early 20th century; today, large-scale deep mining is no longer operational in Britain, but extensive opencast mines continue to work, mostly in Scotland with some in Wales and England.
On this course, you will be introduced to the deposition of the coal-bearing strata of Late Carboniferous age in Britain, and their deformation during the mountain-building events (Variscan Orogeny) at the end of the period. The tutor has run field courses in south Wales where opportunities to study the main coal-bearing strata and their deformation have existed in huge opencast coal operations, and where those rocks exposed are no longer accessible or extant. Such locations, which include bituminous and anthracitic coal seams up to around 2 metres thick, will be illustrated from photographs taken at the time of the visits. Other locations including natural exposures, working and disused quarries and track cuttings, will also be described to provide a stratigraphic coverage up through the coal – bearing strata.  
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 are is assumed.

Thursday, 5 January 2017

Why you should stay back from a lava delta!

Collapse of a Lava Delta

Bath Geol Soc have posted a link about this and I repeat it HERE. I was there in March 2011 but lava flow had closed down for the duration of my visit, but even so, I would have liked to have seen this before I went! 

The videos are fantastic and the explanation very good.