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!

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

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

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.

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