One woman's quest for geological understanding!

Herdman Symposium 2014 – Geoscience Frontiers 5 – Saturday 22nd February 2014

Herdman Symposium

I had yet another fantastic day at the Herdman Symposium 2014 yesterday, and left with my head buzzing and longing for more!

A quick overview is below, with some links and recommended reading, is below, and I will delve further into one or two of the subjects at a later date…

 

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Prof Pete Kokelaar (Liverpool)
“Extreme avalanche mobility: theories, experiments and for real”
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Abstract from Symposium program:

“Catastrophic dense granular flows, such as occur in rock avalanches, debris flows and pyroclastic (volcanic) flows, move as fully shearing mixtures that have approximately 60 vol. % solids and tend to segregate to form coarse­ grained fronts and leveed channels.  Levees restrict spreading of unconfined flows and form as coarse particles that become concentrated in the top of the flow are transported to the front and then advect to the sides in the flow head. Channels become lined with fine-grained deposit, also formed from the flow head; thus the flows create their own stable ‘conduit’ entirely from the front, which in a geophysical context plays an important mechanistic role in facilitating runout. The flow self-organization ensures that low-friction fines at the base of the segregated channel-flow shear over fine-grained substrate in the channel, thus reducing frictional energy losses. In pyroclastic flows and debris flows, which have considerable mobility (substantially reduced friction) attributable to pore-fluid pressures, such fine-grained flow-contact zones form similarly and not only reduce frictional energy losses but also reduce flow-substrate permeability so as to enhance pore-fluid pressure retention . Thus the granular flow self­ organization that produces fine-grained channel linings can be an  important factor in facilitating long runout of catastrophic geophysical flows on the low slopes (few degrees) of depositional fans and aprons around mountains and volcanoes. This talk also presents the latest [unpublished) findings from fieldwork on Mount St Helens, including remarkable evidence for spontaneously formed (roll) waves that moderated behaviour and as well as deposit architecture.”

Prof Pete Kokelaar provided a captivating presentation of his research (past, present and future) – Some papers of interest to read on this topic:

  • Kokelaar, B, Graham, R, Gray, J, & Vallance, J 2014,
    ‘Fine-grained linings of leveed channels facilitate runout of granular flows’
    Earth & Planetary Science Letters, 385, pp. 172-180
  • Woodhouse, M, Thornton, A, Johnson, C, Kokelaar, B, & Gray, J n.d.,
    ‘Segregation-induced fingering instabilities in granular free-surface flows’
    Journal Of Fluid Mechanics, 709, pp. 543-580
  • Gray, J, & Kokelaar, B n.d.,
    ‘Large particle segregation, transport and accumulation in granular free-surface flows’
    Journal Of Fluid Mechanics, 652, pp. 105-137
  • Rowley, P, Kokelaar, P, Menzies, M, & Waltham, D n.d.
    ‘SHEAR-DERIVED MIXING IN DENSE GRANULAR FLOWS’
    Journal Of Sedimentary Research, 81, 11-12, pp. 874-884
  • Johnson, C, Kokelaar, B, Iverson, R, Logan, M, LaHusen, R, & Gray, J 2012,
    ‘Grain-size segregation and levee formation in geophysical mass flows’
    Journal Of Geophysical Research -All Series-, 117, F1, p. F01032

And if this reading tickles your fancy, as it has mine, then you might want to explore further papers of his here.

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Dr James Hammond (Imperial)

“Science without borders: Unravelling the mysteries of Mt. Paektu Volcano, North Korea”
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Abstract from Symposium program:

“Mt. Paektu volcano (otherwise known as Changbaishan in China) is a stratovolcano on the North Korea/China border.  In the 10th century it was responsible for one of the largest eruptions in the last 2000 years, forming a 5 km wide caldera at the volcano summit with ash fall as far away as Japan. More recently (2002-2005) the volcano showed an increase in activity with a marked increase in the number of earthquakes, measurable volcanic deformation and an increase in gas emissions – all pointing to magma recharge beneath the volcano. However, despite such a dramatic history and recent signs of magma movement, the volcano remains poorly understood.

The volcano’s location on the border of two of the world’s most secretive states is a major factor in limiting understanding of its behaviour. In 2011a UK delegation of scientists was invited to North Korea to discuss volcanic hazards and Mt. Paektu volcano with North Korean scientists. This led to a UK-US-North Korean collaboration (the first of its kind) to better understand the volcano. In August 2013 a team of UK/US scientists deployed seismometers and collected geological samples around the volcano. The seismic data is used to image magma storage beneath the volcano and this combined with constraints on historical eruptions from dating and characterising previous eruptions allows us to better understand the potential effects of future eruptions. This work, hopefully the first step in a longer lasting collaboration between the UK and North Korea, is allowing us insights into this enigmatic and potentially hazardous volcano .”

The BBC reported on his ground breaking (both politically and geologically!) work in September 2013: Volcanic sleeping giant opens North Korean co-operation

NERC, who have supported the research, published Science without borders in October 2013

Explore further papers of by Dr. James Hammond here (and on twitter) and his research partner Prof Clive Oppenheimer here.

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Dr Katherine Joy (Manchester)

“Moon impacts: unravelling the history of inner Solar System bombardment”
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Abstract from Symposium program:

“The Moon is an archive of impact cratering in the Solar System throughout the past 4.5 billion years. It preserves this record better than larger, more geologically complex planets like the Earth, Mars and Venus, which have lost their ancient crusts through reprocessing.
Evidence for the lunar impact record comes from both (1) surface morphology and geophysical information derived from remote sensing missions (e.g., the number and size of basins and craters, relative ages of those structures), and (2) the lunar sample collection, which provide evidence of (i) the timing of impact events, and (ii) the nature and sources of bodies impacting the lunar surface.

The lunar impact record itself is controversial with several different models proposed to explain past impact flux. It is generally agreed that rates of impacts were high immediately after the Moon’s formation at -4.5 Ga. All of the Moon’s large impact basins were formed between this time and -3.8 Ga. However, the duration and magnitude of basin-formation is not well known. It may be that there was a sudden spike in bombardment between -3.9 to 3.8 Ga when many basins formed (this is known as the lunar cataclysm hypothesis), or it could be that there was a period of late heavy bombardment lasting from -4.2 to 3.8 Ga. Constraining this record is vital, as whatever happened on the Moon would have also happened on the Earth, affecting our atmosphere and biosphere and having important implications for the onset and proliferation of life.”

More information on Dr Katherine Joy, and a link through to her research and publications, can be found here and on twitter.

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The Geophysics of a veggie/gluten free lunch!

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In addition to the speakers, I had the fortune to spend the lunch hour with Dr Isabelle Ryder (University of Liverpool) who’s research is focused on active tectonics, in particular earthquakes, faults and the rheological structure of the upper lithosphere.  Check out her research and be sure to follow her on twitter!

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Prof Andrew Scott (Royal Holloway)

“Wildfire: The burning issue – the geological history of fire”
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This presentation was of particular interest to me personally – I had no idea it would be! but it has provided me for some fuel (excuse the pun!) and further reading for my project course!

Abstract from Symposium program:

“Fire has been an integral part of terrestrial systems for at least 420 million years. The presence of charcoal in the fossil record acts as a proxy through which it is possible to track the changing occurrence and impact of fires in a diverse range of ecosystem settings. As charcoal frequently exhibits exceptional preservation and is often readily isolated from rocks by maceration, it not only acts as a proxy for wildfire activity but is a valuable palaeobotanical resource, providing both morphological and anatomical data. The full impact of fire related erosional / depositional systems has yet to be fully appreciated, but, in combination with its influence on the atmosphere, climate and the evolution of plants and terrestrial ecosystems, wildfire must be considered a significant Earth System Process.”

Of course, I went straight online to buy his book “Fire on Earth: An Introduction” (For a 25% discount, enter the voucher code VBF95)

More information on Prof Andrew Scott, and a link through to his research and publications, can be found here.

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Prof Simon Conway Morris (Cambridge)

“Eight evolutionary myths: The closing of the Darwinian mind?”
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Abstract from Symposium program:

“Evolution is true, but time to set the feline amongst the columbiformes. “Myths”, not as fairy-tales but as areas of received wisdom that might benefit from a good kicking (apologies; careful reanalysis) . “Mass extinctions”? No doubt they happen and very nasty too, but what is their real significance? “Missing links”? All in favour, but maybe their real importance lies elsewhere. “Extra-terrestrials”, inevitable but “out there” they are keeping rather quiet; how odd. Maybe Fermi was right? And then the big one: Consciousness, a true graveyard of ambition. Watch the materialists huff and puff.  Yes, evolution is true but there is lots to play for.”

An absolutely hilarious presenter – I am truly jealous of the Cambridge students who have studied under his guidance!

More information on Prof Simon Conway Morris, and a link through to his research and publications, can be found here.

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Prof Tim Lenton (Exeter)

“Revolutions that made the Earth”
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Abstract from Symposium program:

“The Earth that sustains us today was born out of a few remarkable, near­ catastrophic revolutions, started by biological innovations and marked by global environmental consequences. The revolutions have certain features in common, such as an increase in complexity, energy utilization, and information processing by life. This talk describes these revolutions, showing the fundamental interdependence of the evolution of life and its non-living environment. We would not exist unless these upheavals had led eventually to ‘successful’ outcomes – meaning that after each one, at length, a new stable world emerged. The current planet-reshaping activities of our species may be the start of another great Earth system revolution, but there is no guarantee that this one will be successful. The talk explains what a successful transition through it might look like, if we are wise enough to steer such a course. Humanity is placed in context as part of the Earth system, using a new scientific synthesis to illustrate our debt to the deep past and our potential for the future.”

More information on Prof Tim Lenton, and a link through to his research and publications, can be found here.

 

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