Wednesday, 22 April 2015

Groundhog explores deep beneath our feet... by Gerry Wildman

To cope with 21st century issues like rapidly expanding cities and demands for natural resources we need clever 21st century solutions. 'Groundhog' is a new digital tool from the BGS which delivers 3D geological models to communities, planners and policy makers. It allows users to understand the issues and solutions that literally lay at their feet. Gerry Wildman, Data and Science Services Manager, explains more...

Geology is a phenomenon that changes at depth. Layers of rock are built up on top of each other over vast quantities of time.  These layers are then subjected to stresses and strains, which fold, fault and deform the ground. Through geological time, older rock layers may be ground down by erosion before younger layers are deposited on top. When considering the geology, it’s important to look not only at the type of the geology you find at the surface, but also how and when this changes at depth. Knowing how these layers change is important in understanding how we can use the ground. For example it can help us to understand where groundwater can flow, where the natural resources are, and what to consider when designing buildings and structures above and below the ground. 

Over the last decade many Geological Surveys across the world, including BGS, have begun to communicate their geological understanding of the ‘subsurface’ through 3D geological models. BGS now has a number of different 3D  geological models ranging from a national resolution ‘fence diagram’ model of the onshore bedrock geology: the GB3D  bedrock model to shallow, local-scale models,  typically for use in ground investigations, groundwater studies and tunnelling projects.

London Geological Model
Recently, BGS has begun releasing data from a selection of their local-scale models in their Groundhog system. Developed by BGS, Groundhog is a tool that is used to deliver geological models over the web. It allows the user to explore the 3D models by creating ‘virtual boreholes’ or ‘virtual sections’.  Groundhog delivers the results straight to the user as pdf reports. Currently 3D models for London, Manchester and part of Suffolk are available in this system, with more planned.

The ethos behind Groundhog is to provide a service that conveys complicated geology in a simple way. As it runs in a web browser, it removes the need for expensive and specialised software, enabling anyone to use the models. But behind the simplicity is some very clever stuff. In creating the underlying models BGS uses a range of methods to capture our geological understanding varying from direct interpretations by geologists to semi-automated modelling involving advanced maths. The methods used depend on the geological situation and how much data is available. Each model takes account of existing BGS experience and data that may include our vast collections of borehole logs, seismic lines and regional geophysical data.

Screenshot from Groundhog, visit here
To enable Groundhog to produce virtual boreholes and sections, the models are represented behind the scenes as a stack of 2D elevation grids, each grid representing the stratigraphic base of one geological layer, and a further grid to represent the ground surface (the digital terrain model, DTM).  The grids are then converted to a binary format for use in Groundhog making them much quicker for the drawing tool to access the required data points within them.  A simple database provides an index to the available models and their grid file and fault file layers. By querying a stack of grids for a given X,Y position on a map, Groundhog can create a vertical log through the 3D model.  A series of vertical logs along a specified line can be used to create a cross-section. By considering a collection of vertical logs sampled on a 2D grid with respect to a fixed or DTM-relative elevation value, a horizontal slice can also be produced.

For more information, or to order your own virtual borehole or section, please see our website. Every Wednesday throughout April and May 2015 Groundhog reports are half price, follow #3Dgroundhog on Twitter for more links and info.

Gerry

Sunday, 12 April 2015

Mud, monsters and murders: can geology really help to solve crime?...by Kirstin Lemon

The recent NI Science Festival was the first of its kind in Northern Ireland and attracted thousands of people to an amazing diversity of science events across the country. This eclectic mix included traditional lectures and demonstrations, and a range of not so traditional such as theatre, comedy, music and film.

One of the less conventional events that took place was called 'How do volcanoes solve crimes?' and was jointly organised by Dr Alastair Ruffell and Dr Jenny McKinley from the Queen's University of Belfast, and Dr Kirstin Lemon from the British Geological Survey. Hosted by the Ulster Museum, this unusual event looked at forensic geology and how it could be used to solve a fictional crime based in the museum itself. A crime scene was created, with the famous 'Minnis Monster', a fossil Ichthyosaur, being stolen and children were asked to see if they could find where the monster was hidden using the mud found on the shoe of the key suspect.

Sediment on wheel arches of cars are often used to place a car
at the scene of a crime. Such evidence was used in the
Soham murder case
What exactly is forensic geology? To put it simply, it is using earth-related material such as minerals, pollen/spores and organic matter as part of a forensic investigation. The concept was probably first used by Sir Arthur Conan Doyle in his Sherlock Holmes books when Sherlock was able to identify where an individual had been using the clay found on their shoe. But forensic geology is not just in fiction as it has been used to solve many crimes including a high profile case that involved locating a body of a murder victim in March 2005 based on soil material believed to be from the body deposition site.

How does forensic geology work? Generally, earth-related materials are collected from a suspect's clothing, footwear, vehicles or dwellings and are used as a comparative material from the crime scene.  Given the sheer amount of potential variables it can be a rather difficult line of evidence to pursue. However, if a number of different analytical techniques are used then the chances of success are much higher. Dr Barry Rawlins, the Soils and Landscape Team Leader with the British Geological Survey has worked on forensic geology and has outlined the key techniques used:

1. XRD or X-Ray Diffraction is used to detect any crystalline or partially crystalline substances in the sample. The advantage of this technique is that it can be used on event the smallest of samples. It is very useful for identifying clay minerals and can help to determine the provenance of rocks and soils.

2. SEM or Scanning Electron Microscopy is used to produce images at a much higher spatial resolution than using a conventional microscope. It also allows for chemical analyses on isolated areas of the specimen and is particularly useful for soil samples.

3. Molecular Organic Matter Signatures can be looked at to identify specific plant communities from the soil sample and thus helping to identify where it came from.

4. Palynology is the study of organic microfossils and their modern counterparts and can be used to identify bedrock or the bedrock that soil samples originate from.

The mineralogy of geological samples was used to identify 
the provenance of aggregate used to bury bodies in a trench 
in Devon. The thin section above is seen under polarised light
A number of these techniques rely on soil samples, all of which formed in the last 10,000 years. Their characteristics are closely related to the parent material from which they formed including underlying bedrock and any Quaternary material such as glacial deposits. Once a soil is identified, its provenance can be determined by combining this with detailed geological knowledge of an area. This ultimately can prove or disprove the location of a crime scene or the presence of a suspect at one.

Forensic geology is being used increasingly to solve crimes, especially those of an environmental nature. Whilst the NI Science Festival event was purely for fun it played a vital role in raising the awareness of this specialist branch of geology, and the role that organisations such as the British Geological Survey play in this.

Given that 2015 is the International Year of Soil and the Year of Mud, then perhaps now is the time to raise the profile of this exciting science.

For more information on forensic geology at the British Geological Survey contact Dr Lauren Selby at laurenj@bgs.ac.uk or Dr Barry Rawlins at bar@bgs.ac.uk

Reference:

Rawlins BG, Kemp SJ, Hodgkinson EH, Riding JB, Vane CH, Poulton C & Freeborough K 2006. Potential and Pitfalls in Establishing the Provenance of Earth-Related Samples in Forensic Investigation. Journal of Forensic Science, 51, 4: 832-845.








Thursday, 9 April 2015

Isotopes and the bones and teeth of King Richard III ... by Catherine Pennington

Professor Jane Evans (right) and Dr Angela Lamb (left) in their lab in NIGF
Professor Jane Evans (right) and Dr Angela Lamb (left) in their lab in NIGF
Professor Jane Evans and Dr Angela Lamb work in the NERC Isotope Geosciences Facilities (NIGF) at the BGS in Keyworth.  NIGF is one of the largest isotope laboratories in Europe for studying naturally occurring isotopes. 

Jane and Angela front the Science-Based Archaeology programme where they use isotopes to uncover information about the past. 

Some of Jane and Angela’s work is not quite what you might expect.  They have been involved with assisting the police with forensics, identifying fraudulent ceramics, mapping the migratory patterns of fallow deer, understanding how humans have transported chickens around the world and reconstructing past agricultural practices.  More lately, they have been involved with the much reported lifestyle of King Richard III (see below).

But what exactly are isotopes?  How do we use them to date rocks? What can isotopes in teeth and bones tell us?  Jane explains in this video:



King Richard III's teeth

King Richard III died at the Battle of Bosworth in 1485 and teams from the University of Leicester and the Richard III Society uncovered this warrior king’s remains under a council car park in 2012.  The skeleton was then tested to confirm his identity and to try to reveal how he died.  Jane and Angela were asked to find out more about his lifestyle and movements.  They were given a pre-molar tooth and small pieces of femur and rib bone as these all form at different stages of life, giving a range of information across the king’s lifetime as Angela explains:
By looking at the oxygen and strontium isotopes in his bones and teeth we were able to look at where he lived through his life. The teeth, which form in childhood, confirmed that Richard had moved from Fotheringay castle in eastern England by the time he was seven and that he had moved back to eastern England as an adolescent or young adult.  We then looked at the dietary isotopes, carbon and nitrogen, to look at how his diet changed throughout his life
One of the most important findings from their isotope analysis was that there were marked changes in his diet when Richard became king in 1483; he began eating a diet only the highest aristocracy could afford.  This included freshwater fish and birds, such as swans, crane, heron and egret.  In addition, the bone chemistry suggested he was drinking more wine during his short reign as King and reinforces the idea that food and drink were strongly linked to social status in Medieval England. 

You can read more about the work Angela and Jane did by reading their paper:


Professor Jane Evans is the Head of Science-Based Archaeology at the NERC Isotope Geosciences Facilities.

Dr Angela Lamb is a Research Scientist within the NERC Isotope Geosciences Facilities.

Both work within the Centre for Environmental Geochemistry, a joint venture between BGS and the University of Nottingham.

Catherine

Wednesday, 1 April 2015

Why learn good Science Communication?... by Jonathan Dean

Our scientists never stop striving to improve their understanding of the world around them. Equally they never stop learning new ways to better communicate their work and discoveries to the wider world. One such scientist is Jonathan Dean, a Postdoctoral Research Assistant at BGS, who's just back from a 2 day public engagement course run by NERC. Here Jonathan reflects on the importance of good science communication and the skills learnt on the NERC Engaging the Public with your Research training course...

Public engagement – letting non-scientists know what science we’re doing with their taxes – is important. Many people are interested in finding out, for example, when humans evolved from apes, what caused an extreme flooding event and if there is life on Mars, but they are going to be left in the dark unless they trawl through academic journals on their evening commute (unlikely) or unless we make an effort to reach them. We can get our message out to the public in a variety of ways, for example via the media, in blogs on our websites and at talks in schools. Lots of our work could benefit society – we might have discovered mineral deposits that could stimulate economic growth, found a way of reducing the pollution emitted from cars or established how changes in solar activity influence the Earth’s climate. But if policy-makers don’t know what we’ve found, then policy can’t be changed and our findings might go to waste.

NERC - the parent body of BGS
We began our training course with instruction from a BBC News science reporter on how to write a good press release. We found that they are written the opposite way round to how we’d write up our results for a peer-reviewed journal – the snappy summary of the findings, which would be in the conclusion of a paper, should come first, followed by more detail about why it is important and how we carried out the research. Unless their imagination is captured within the first few seconds, journalists will stop reading and move onto the next press release, and our research will never find it onto the Today programme or into The Times (other media outlets do exist).

We then learnt about how to design public engagement activities, such as talks in school or in pubs, before moving onto radio interviews. While listening to the sound of your own voice played-back in front of everyone is never enjoyable, our practice interviews were really useful. We realised the importance of avoiding jargon (for example using the word ‘results’ rather than ‘data’) and in coming across enthusiastic – making yourself smile during the interview helps this! Finally, we had the chance to produce our own media, by making a podcast. I played the role of a radio presenter interviewing two people about fracking.

The course takes place in the NERC office in Swindon 9 times a year and can be attended by anyone who works for NERC or holds a NERC grant, including NERC PhD students and PDRAs. I would thoroughly recommend it as a really useful and enjoyable course that gives you new ideas for engaging with the public and more confidence when dealing with the media.

Jonathan
Find me on Twitter @jrdean_uk