Evidence of ‘super henge’ surrounding Stonehenge

Scientists have unveiled a remarkable new picture of Stonehenge and its surrounding areas, including the remains of an even bigger ‘super henge’ nearby.

The mammoth project, led by Prof. Vince Gaffney at the University of Birmingham in conjunction with the Ludwig Boltzmann Institute for Archaeological Prospection and Virtual Archaeology, is likely to transform our knowledge of this iconic landscape.

For the project, Dr Richard Bates of the School of Earth and Environmental Sciences, used remote sensing techniques and geophysical surveys to discover hundreds of new features which now form part of the most detailed archaeological digital map of the Stonehenge landscape ever produced.

Electromagnetic survey results
showing the outer bank at Durrington Walls
marking the circumference of the new super henge

The startling results of the survey include 17 previously unknown ritual monuments dating to the period when Stonehenge achieved its iconic shape. The project has also revealed completely unexpected information on previously known monuments. Arguably the most significant relates to the Durrington Walls ‘super henge’, situated a short distance from Stonehenge. This immense ritual monument, probably the largest of its type in the world, has a circumference of more than 1.5 kilometres (0.93 miles). The geophysical results have provided a new model of this feature that encompasses the vast monument in one complete picture. Geophysics used in archaeology may never be the same again and the team now hopes to apply a similar approach to other iconic sites. In Orkney, Dr Bates is currently applying some of the new techniques to study the landscapes around the henges of the Ring of Brodgar and Stones of Stenness.

The project is the subject of a BBC documentary Operation Stonehenge: What Lies Beneath, which aired on BBC 2 on 11 September. [press release].

The project recently was awarded Research Project of the Year 2017 by Current Archeaology magazine.

INTRIGUED: INvestigating The Role of the North Pacific In Glacial and Deglacial CO2 and Climate

The geological record offers an invaluable window into the different ways earth's climate can operate. The most recent major changes in earth's climate, prior to modern climate change, were the Pleistocene ice ages. These feature growth and collapse of massive ice sheets, rapid shifts in rain belts, and abrupt changes in ocean circulation. Changes in atmospheric CO2 are intimately linked with these ice age climate changes, but despite decades of effort, we still don't fully understand their driving mechanisms.

The aim of the newly NERC-funded research by Dr James Rae of the Department of Earth and Environmental Sciences is to transform our understanding of ice age CO2 and climate change, by investigating how the deep Pacific stored CO2 during ice ages, and released it back to the atmosphere during deglaciation. Although all leading hypotheses for ice age CO2 change involve CO2 storage in the deep ocean, the role of the Pacific remains unknown. As the Pacific contains half of global ocean volume, and ~30 times more CO2 than the atmosphells, whichere, its behaviour will have global impact. Our work will involve making geochemical measurements on fossil shells taken from sediment cores from the deep Pacific Ocean. These shells - called foraminifera - record the chemistry of the surrounding water at the time they grow, so by making measurements on them down the length of a sediment core, we can read back through the history of ocean circulation and CO2. A particular focus of our grant is the boron isotope composition of these sh reflects ocean pH and CO2. The new St Andrews Isotope Geochemistry labs at the University of St Andrews are among the first in the world to have be built fully boron-free, allowing us to be at the forefront of this cutting-edge technique.

The research is based at St Andrews, but features a team of leading scientists from around the world, including the Universities of Bristol, Kiel, Oregon, McGill, and ETH Zurich, the Woods Hole Oceanographic Institute and Scripps Institute of Oceanography USA, the Alfred Wegner Institute for Polar Research Germany, and radiocarbon facilities in Glasgow and California.

The project will ultimately improve understanding of CO2 exchange between the ocean and the atmosphere, which is an important factor for predicting the path of future climate change.

Tree rings unveil temperatures of the last millenium

High on mountains across Alaska, Canada, Europe and Russia near the upper or high latitude tree line, even the hardiest of conifers are at the edge of survival. Their annual rings tell a story of extreme cold that limit their growth and of warmer years that allow them to flourish. By analysing samples from these living trees and fallen timbers, researchers are able to reconstruct past temperature change.

A new international consortium of scientists, led by Dr Rob Wilson of the Department of Earth & Environmental Sciences, has collated a network of such tree-ring archives to derive a history of temperature fluctuations across the entire Northern Hemisphere. The N-TREND consortium (N-TREND stands for Northern Tree-Ring Network Development) was created to develop a global database of tree-ring research that improves on previous efforts for developing large-scale temperature reconstructions across the hemisphere. The consortium was devised to provide a collective platform where participants are all on the same page with respect to identifying not only gaps in the hemispheric network, but also facilitating the communication and training of new methodological approaches that can further improve tree-ring based temperature reconstructions.

The consortium’s first research paper, appearing in the current issue of Quaternary Science Reviews, provides a view of past Northern Hemisphere temperature changes over more than 1,000 years. It reveals a longer and warmer Medieval period than previous temperature reconstructions suggested, from around 850 to the end of the 11th century, with a peak in the 1160s. It also shows how the two coldest decades—1812-1821 and 1832-1841, both during a period known as the Little Ice Age—are followed by near continuous warming until present. The new paper takes a close look at some of the challenges of previous historic temperature reconstructions, explaining why reconstructions using multiple proxy archive sources—such as tree rings, ice cores, lake sediments etc, or mixing seasons expressed by different archives — can end up with ambiguous results when trying to understand past climatic variability and forcing.
A second paper will soon be submitted that will look at spatial temperature variations across the Northern Hemisphere for the last millennium. Such spatial analyses will help answer questions about the spatial extent of Medieval Warm Period, for example, and through comparative analyses with global climate models could help attribute the forces behind such past temperature ch
ange.

Columbia University links: Lamont-Doherty Earth Observatory, Blog
"Last millennium northern hemisphere summer temperatures from tree rings: Part I: The long term context", Quaternary Science Reviews Volume 134, 15 February 2016, Pages 1–18, doi:10.1016/j.quascirev.2015.12.005

Carnegie Trust success for coral reef team

Dr Heidi Burdett, a MASTS Research Fellow in the Department of Earth and Environmental Sciences (DEES) has been successful in securing a Collaborative Research Grant from the Carnegie Trust for the Universities of Scotland, together with Drs Nick Kamenos (University of Glasgow) and Sebastian Hennige (Heriot-Watt University).

Millions of people around the world depend on coral reefs for their livelihood. However, in recent years the 'health' of corals, and their associated ecosystems, has deteriorated in many areas putting communities at risk. This Carnegie-funded project will investigate the response of tropical corals to environmental change, helping us to better understand the observed deterioration in coral reef ecosystems.

Related article: Effects of reduced salinity on the photosynthetic characteristics and intracellular DMSP concentrations of the red coralline alga, Lithothamnion glaciale. Marine Biology 162:1077–1085: DOI 10.1007/s00227-015-2650-8

The first common market

Long before we had mountains of grain and vast lakes of wine accumulating to excess across the continent our ancestors had worked out that the best entrepreneurial way to stay ahead was through trade with as wide a market as possible. A study to be published in Science this week describes the first evidence for grain traded across Europe 8000 years ago, 2000 years before the accepted beginning of farming in Britain.

Divers at Bouldner Cliff with flints (The Maritime Trust)

The team of scientists, which includes Dr Richard Bates from the Department of Earth and Environmental Sciences at the University of St Andrews, Prof. Vincent Gaffney from the University of Bradford and the Universities of Warwick, Birmingham and Southampton studied two submerged sites at the extreme ends of Britain, off the shores of the Isle of Wight and Orkney, to discover sediment sequences that contained wheat grains. In the southern site, einkorn DNA (an early form of farmed wheat) was collected from material that had previously formed a land surface which was later sealed by sediment and submerged by rising sea levels. When the grain was dropped, the Mesolithic people were leading a hunter-gatherer existence as farming had only spread as far as Southern Europe. As the einkorn was not native to Britain, in order for it to have reached this site, there must have been contact between the people of Briton and the Neolithic farmers. This contact could even have been across narrow land bridges over what is now the English Channel and southern North Sea.

Flints from Bouldner Cliff
(The Maritime Trust)

The novel ancient sediment DNA analysis used in the study could unlock many other secrets of long lost areas, especially those surrounding our coasts. These areas were once at the heart of different societies but the locations make their study particularly challenging. For St Andrews, the work continues in the Orkney Isles around the iconic Neolithic landscapes where the team will use these techniques to continue investigating the land of the ancestors who constructed the monuments at these sites. [press release]

Science article: Sedimentary DNA from a submerged site reveals wheat in the British Isles 8,000 years ago (DOI: 10.1126/science.1261278).
BB News:  Scientists find evidence of wheat in UK 8,000 years ago

The Southern CO2 that helped end the ice age

Scientists have long puzzled over the processes that caused CO2 to rise and help end the last ice age. Leading theories have involved increased CO2 release from the deep ocean around Antarctica, but there has been no direct evidence to prove this happened.

Our study used the geochemistry of tiny planktonic fossil shells to reconstruct the amount of CO2 in waters around Antarctica during the end of the last ice age.  We were able to show, for the first time, that CO2 was indeed released from the Southern Ocean to the atmosphere, helping warm the planet and melt back the ice sheets that would have covered Scotland and much of the rest of Northern Europe and America.

Dr James Rae, of the Department of Earth and Environmental Sciences, who co-authored the study, said “intervals of CO2 and climate change in the past offer a fantastic opportunity for us to better understand the path of future climate.  As the ocean currently takes up about a third of the CO2 emitted by humans, it’s important to understand the controls on CO2 exchange between the ocean and the atmosphere so we can predict how ocean CO2 uptake may change in the future.  It’s also striking to think that CO2 change has contributed to climate changes in the past as dramatic as melting back a mile of ice on top of Scotland, and you’ve got to wonder what adding the same amount of CO2 to the atmosphere, but 100 times faster, will do to climate in the years to come.” [Nature 518, 219–222 (12 February 2015) DOI: 10.1038/nature14155, "Boron isotope evidence for oceanic carbon dioxide leakage during the last deglaciation"] [press release]

Tree-rings reconstruct the South Asian summer monsoon index over the last millennium

The South Asian summer monsoon (SASM) is a major atmospheric synoptic climate system affecting nearly a quarter of the human population. Dr Rob Wilson, Department of Earth and Environmental Sciences, with co-authors from China have published a 1000-year-long reconstruction of SASM in the Nature Group journal Scientific Reports. They utilised 15 tree-ring chronologies to reconstruct the SASM index over the last millennium. The record generated is significantly correlated (r=0.7, p<0.01) with the instrumental SASMI record on annual timescales; this correlation is higher than that obtained in any previous study. The reconstructed SASMI captures 18 of 26 (69%) recorded historical famine events in India over the last millennium; notably, 11 of 16 short events with durations of 1–3 years are accurately depicted in the reconstruction. Moreover, the reconstructed SASMI is positively correlated with variations in total solar irradiance (TSI) on multi-decadal timescales implying that variations in solar activity may influence the SASM. Epoch analysis additionallyindicates that volcanic events may also drive some of the SASM variability about 2 years after major eruptions.

Figure: Time series of the reconstructed South
Asian summer monsoon index (SASMI) and total
solar irradiance (TSI) over the last millennium.

Shi, F., Li, J., and Wilson, R. 2014. A tree-ring reconstruction of the South Asian summer monsoon index over the past millennium. Scientific Reports, 4 (6739). DOI: 10.1038/srep06739.

The Building Blocks of Life

Searching for the essence of life on Earth, understanding climate change and investigating the spread of diseases - these are a few examples of the fundamental research that academics at St Andrews will be tackling with new equipment won under a competitive £0.5M NERC grant! This cutting edge analytical set-up combines a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS) with a gas chromatograph (GC), and will be the first of its kind in the EU (and only the third in the world!). The NERC capital equipment fund bid was led by Drs Andrea Burke, James Rae, and Heidi Burdett from the Department of Earth and Environmental Sciences, supported by an interdisciplinary team including Profs David Paterson,  Ian Johnston, and Derek Woollins from the Schools of Biology and Chemistry.
 

The state-of-the-art clean mass spectrometry lab where the new
equipment will be housed

One of the exciting major applications for this new equipment is the measurement of sulfur isotopes. The study of sulfur has both pure and applied uses, as it is a key element on scales ranging from nano to global, and in processes ranging from climate forcing by volcanic eruptions, to the processing of sulfur-rich crude oils. This new analytical set-up permits the measurement of sulfur isotopes on samples a thousand times smaller than previously possible, and will provide valuable new information on climate sensitivity, metabolic pathways, and Earth resources and their recovery.

 For further information on this, contact Dr Andrea Burke.

Sulfate on the early Earth – how low was low?

Findings recently published in Science (“Sulfate was a trace constituent of Archean seawater”, DOI: 10.1126/science.1258966) suggest that sulfate – a key biological nutrient – could have been incredibly scarce in the Earth’s ancient oceans.

Sulfur is a crucial component of biomass and an important source of energy for microbial metabolisms. It also plays a central role in regulating atmospheric chemistry and global climate over geologic timescales.

Research vessel on Lake Matano, Indonesia.
PHOTO by Sean Crowe, University of British Columbia.

Researchers led by Dr Sean Crowe, a lead author of the study in the Departments of Microbiology and Immunology, and Earth, Ocean and Atmospheric Sciences at the University of British Columbia, collected samples from Lake Matano, Indonesia—a sulfate-poor modern analogue for the Earth’s Archean oceans – to examine the isotope effects associated with sulfur metabolisms under early Earth conditions. The team used state-of-the-art mass spectrometric approaches developed at California Institute of Technology to demonstrate that microorganisms in this lake fractionate sulfur isotopes at concentrations orders of magnitude lower than previously recognized.

“These results suggest that sulfate levels in the Archean could have been thousands of times lower than today, which would have had important consequences for the cycling of sulfur in the oceans and atmosphere, and for the evolution of early microbial ecosystems”, says Dr Aubrey Zerkle, a Lecturer in the Department of Earth & Environmental Sciences and collaborator on the study. Two additional papers published in the same issue of Science used similar techniques to examine sulfur isotope signatures of in ancient sediments from ~2.5 billion years ago. These studies suggest dynamic spatial and temporal variations of seawater sulfate during that time, supporting a low-sulfate scenario. However, both indicate that microbial ecosystems based on sulfur cycling still thrived, despite the lack of sulfate.

EGU "Outstanding Young Scientist" award to DEES biogeoscientist

Dr James Rae of the Department of Earth & Environmental Sciences has been awarded the European Geosciences Union (EGU) "Outstanding Young Scientist" in the Biogeosciences (BG) Division as part of their announcement of 35 recipients of next year’s Union Medals and Awards, Division Medals, and Division Outstanding Young Scientists Awards.

The individuals, from both European and non-European countries, are honoured for their important contributions to the Earth, planetary and space sciences.

James' research focuses on reconstructing past climate change and its causes, with particular interests in the cause of recent glacial-interglacial cycles, and climate changes over the Cenozoic. To study these questions, James uses geochemical measurements on fossils, sediments, water and ice, with a special focus on the boron isotope proxy for pH. Recent research highlights include new estimates of tropical ocean temperatures over the last 5 million years (DOI: 10.1038/ngeo2194), and a new mechanism for the end of the last ice age (DOI: 10.1002/2013PA002570).

The recipients will receive their prizes at the EGU 2015 General Assembly, which will take place in Vienna on 12–17 April  2015.

The search for Alien life

Working alongside colleagues at NASA, University of Washington and UNAM, Mexico, Dr Mark Claire of the Department of Earth and Environmental Sciences, has discovered that signs previously thought to confirm the presence of life on alien planets, might not be as definitive proof as thought.

Whilst searching for life on other planets, astronomers rely on finding gases – such as oxygen, ozone or methane – in the planet’s atmosphere, as these are thought to be significant signs of the existence of life.

However, the research published this week in The Astrophysical Journal, proves that the existence of one of these alone is not enough to predict the presence of organic life. The research strengthens the belief that the existence of detectable levels of oxygen, ozone and methane together would be a convincing sign of life on another planet. [full article: doi:10.1088/0004-637X/792/2/90] [press release]

A boring billion years of Earth evolution

Research led by Profs Peter Cawood and Chris Hawkesworth of the Department of Earth & Environmental Sciences has shown that Earth’s middle age (from 1.7 to 0.75 billion years ago) was characterised by relative environmental stability with little crust-building activity, no major fluctuations in atmospheric composition and few substantial changes in the fossil record. In contrast more volatile events such as major ice ages and changes in oxygen levels occurred before and after.

The study suggests that gradual cooling of the Earth's crust over time may have been the cause of this middle age stability. Prof. Cawood is quoted: "Before 1.7 billion years ago, the Earth's crust would have been substantially hotter, meaning that continental plate movement may have been governed by different rules to those that operate today; 0.75 billion years ago, the crust reached a point where it had cooled sufficiently to allow modern-day plate tectonics to start working, in particular allowing subduction zones (where one plate of the crust moves under another) to form. This increase in activity could have kick-started a myriad of changes including supercontinent break-up and changes to levels of key elements in the atmosphere and seas, which in turn may have induced evolutionary changes in the life forms present."

The research was presented at Goldschmidt 2014 in Sacramento, California, USA. [Abstract]

“Earth's middle age”, Cawood, P. A. & Hawkesworth, C., 2014, Geology; doi: 10.1130/G35402.1 [Article]

In August, Earth's middle age research has sparked inspiration of a poetic nature for national science week: Geology Sonnet 4

New research centre at St Andrews: CATCH

The Centre for Archaeology, Technology and Cultural Heritage (CATCH) is a multi-disciplinary centre that brings together researchers from across the University of St Andrews. The Centre promotes research into all aspects of past human activity from across the globe, with the aim of making our research accessible to the widest audience as possible. The Centre brings together arts and sciences in order to investigate how humans have been influenced by, and changed, their environment.

The Schools, Departments and Units involved in CATCH are: Art History, Classics, Computer Science, Earth and Environmental Sciences, Geography & Sustainable Development, History, Museum Collections Unit and Social Anthropology.

"Digitising cave art will prevent it being lost forever"
New Scientist, April 2014

New at St Andrews: Institute for Data-Intensive Research

The St Andrews Institute for Data-Intensive Research (IDIR) is a new institute set up to provide a focus for research and teaching activities across the University driven by access to “big data”. 

IDIR will bring the University’s strengths in humanities and social sciences with those in computer, mathematical, life, and physical scientists to share insights and techniques. IDIR results from the enormous volume of activity taking place across the University that could broadly be described as data-driven – from data science, through digital humanities and digital social science, to digital medicine, which all share common characteristics. They are exploring new techniques and opportunities brought about by the availability of large volumes of data and the processing power needed to manipulate them.

Some of the Schools included are Computer Science, Mathematics & Statistics, Physics & Astronomy, Medicine, Chemistry, Biology, International Relations, Earth and Environmental Sciences and History.

New lab to unravel the mysteries of Earth and life

On Thursday July 17th, Drs Aubrey Zerkle and Mark Claire held a grand opening for their new geobiology laboratory space in the Bute building. Approximately 40 members of staff from the Department of Earth and Environmental Sciences were in attendance, as the laboratory was formally christened the "Peter James Clark Centre for Philosophical Geobiology".

The interdisciplinary laboratory will be dedicated to studying the links between geochemistry and biology over Earth history, as evidenced in modern environments and recorded in the rock record.
 In just two weeks’ time, the lab already has in excess of 15 occupants, including post-doctoral researcher Gareth Izon and PhD student Colin Mettam, who are working with the PIs on a NERC-funded project to unravel the interplay between biological forcing and atmospheric chemistry recorded in 2.5 billion year old sediments from South Africa and Western Australia.

It is also supporting a host of undergraduate researchers starting dissertation projects and summer internships on a wide range of cross-disciplinary projects, including:

• geochemistry of Mars analog soils from the Atacama desert (Chile), 
• sulfur cycling in Earth’s oldest well-preserved microbial mats, 
• nutrient cycling in redox-stratified Lake Kinnert (Israel), and 
• paleoenvironmental characterization of the world’s first phosphorite deposits (http://univstandrews-research.blogspot.co.uk/2014/05/two-billion-year-old-microbial.html).  Exciting stuff! 
  

  

  Nicolette Meyer (Geology undergraduate) distilling sulfur
  from 2.6 billion-year-old pyritized microbial mats

  

  Gareth Izon (right) solving the mysteries of the Neoarchean
  atmosphere and Mark Claire (left) extracting atmospheric salts in
  soils from the driest place on Earth (the Atacama Desert)

The somewhat whimsical name for the lab was chosen to honour Professor Peter Clark, retired Professor of Philosophy and member of the Principal's office, whose efforts were instrumental in pushing the long-awaited project forward. "We will attempt to learn from the philosophers by always asking ourselves and our students to contemplate the larger meaning of our scientific results," said Co-PI Dr Mark Claire upon unveiling the plaque above the door. Dr Tony Prave, Reader in Earth Sciences and Director of Research for the department was also recognized during the short ceremony for his continued support and inspiration.