Markus Guentner – Empire

As a geologist, I’m always fascinated to hear artistic perceptions of our restless, constantly evolving planet. Markus’s first album on ASIP, Theia, was a magnificent, swirling mass of immense power, representing the collision of two bodies in the solar system, resulting in the separation of the Earth and Moon. Empire, for me, continues the story of Earth.

Offworld picks up from where the final hints of Cavus left off, with ominous, cavernous pads rooted in deep time, the planet healing, recrystalising, and the first electromagnetic sweeps of Earth’s core juddering to life. The pads give way to Markus’s trademark looping hypnosis, an early indication of the many cycles active on Earth. Those cycles become evident in Refraction, with the advent of liquid water cascading behind Julia Kent’s haunting cello. Meanwhile, deep processes swell and wane, tectonics underway, the deep earthquakes pulsing through with soothing regularity. We are submerged into young oceans in Fura, hidden away with the earliest life that begins to emerge halfway through, first into the shallows, then into the glittering sunlight. Rain joins the sunlight, creating a utopia for life, a world of plenty, balanced ecosystems, a halcyon daze of early life provided by bvdub’s rousing piano on Kuria.

Geological cycles occur over varying timescales, some hundreds of years long, some many millions. Markus echoes that with a plunging back into dark times in Nun. Perhaps a sudden mass extinction has wiped out vast swathes of life on earth. But it blossoms back into life in Halo, a wonderous bounty, a cornucopia alluded by the heavenly harp from Tom Moth. The journey continues on into New World Order, perhaps the most contemplative piece on the album. Does it represent dark times ahead for planet Earth? Its slow, bass-laden tones could certainly be interpreted that way. But it doesn’t just speak of gloom, as there’s trepidatious high notes sung by the choirs at Markus’s fingertips. Do we take this as a sign of something good to come, that perhaps there is still chance for mankind to wrest Earth from the edge of the precipice at which we’ve placed it?

Empire is another fantastic album from Markus in a line of fantastic albums. But it’s more than that, it showcases Markus’s complete mastery over his use of music in creating an enthralling narrative. It is surely one of his finest pieces, and that is no mean feat, given how highly I rate his other albums. The scientist in me is thoroughly in wonderment with the tale told, its cyclicity, and its attention to detail that almost reads like a textbook of Earth history. The rest of me is entranced by the wonderful array of sounds, textures emotions portrayed in this beautiful piece of work.

Markus Guentner – Empire is available to preorder here.

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GLWG 18 – Inverness, Moray Firth and Nairn, September 2017

I’m rather excited to be attending the 19th GLWG trip in September this year because I get to visit Iceland. I can barely wait, and in the excitement, it had me looking back over the report I wrote for last year’s GLWG trip to Inverness, the Moray Firth and Nairnshire, to look at the excellent glacial geomorphology preserved since deglaciation of the Celtic ice sheet. I thought I’d share this report with you via my blog, but it was also published first in the Quaternary Newsletter (QN 144, Feb 2018) of the QRA. So here it is:

JOINT QRA/GLACIAL LANDSYSTEMS WORKING GROUP FIELD MEETING 18

Nairn and the Inverness Firth – 26th-29th October 2017

Introduction

This year’s annual Glacial Landsystems Working Group trip, now in its 18th year, was to the area around Nairn and the Inverness Firth. The trip ran from Friday 27th October until Sunday 29th October with an optional extra day prior to the trip on the 26th October. The trip was well attended, with 37 attendees at all stages of careers from PhD, through professorship all the way to retirement, as well as attendees from industry and heritage and those just attending for personal interest.

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Figure 1.
(Most of) the field meeting attendees at the Daless Viewpoint. Photo: Dave Evans

Optional day – Thursday 26th October – Cairngorm

The optional day was a visit to the slopes of Cairngorm to give an overview to the Devensian and Holocene history of the mountainous region. After an introduction to the area from Martin Kirkbride and Adrian Hall, we were led into the hills, past the Younger Dryas ice limit and into Coire an Lochain, up to the Great Slab. Here evidence was presented for and against the presence of a Late Holocene glacier. The Great Slab is a clean, low angle (25-30°) face of granite which has on either side two ridges which converge in a downhill direction, but do not meet underneath the slab itself. These ridges are interpreted to be ice-marginal moraines and were considered not to meet due to later avalanching processes removing their downhill extent. Martin provided a good deal of evidence to support the presence of a small glaciation but welcomed ideas which would explain the geomorphological evidence. A lively discussion ensued, despite the rapid deterioration in weather conditions, with members of the party arguing for avalanching processes building up the ridges. Further reading on the evidence for, and modelling in support of, a Little Ice Age glacier in Coire an Lochain can be found in Kirkbride et al. (2014) and Harrison et al. (2014).

After a rapid fish supper, introductory talks were given that evening by Jon Merritt, Clive Auton, Emrys Phillips, and Callum Firth, at the quirky Pagoda events venue in Grantown. During these talks we were introduced to the late Quaternary history of the area and shown many fantastic images of the field areas we were to visit over the following few days. Inevitable discussions broke out about the longer-term evolution of the area, as well as the short-term post-glacial sea level history, but as they were threatening to reduce pub time before last orders, they were remembered and saved for the specific field localities we would be visiting.

Day 1 – Friday 27th October – Sites close to the Moray Firth coast

Thankfully, the Friday morning dawned bright and cheerful for a classic Scottish autumn day, with the sun’s first rays irradiating the autumnal arboreal hues. The convoy set off (note- try not to get stuck behind an old BGS Hilux that produces more black smoke than a hydrothermal vent) through the melt-water channel of the Slochd, driving past Inverness and reaching our first stop for the day.

Site 1 – Alturlie Point

The first stop was to visit the active Bothyhill gravel pit to see the deltaic sequences of the Bothyhill Gravels Member of the Alturlie Gravels Formation. Unfortunately, quarrying activity has reduced the impact of the site, and the kettle-hole infills which were once visible have been removed. Kettle holes to the south of the gravel pit lie topographically lower than the top of the delta/subaqueous fan complex, indicating the presence of ice whilst the sand and gravel was being deposited.

Site 2 – Ardersier Peninsula

Further to the east, the coastline becomes delineated by a large push moraine, running east-west, before arcing to north-south at Ardersier. The push moraine itself is evidence of the Ardersier Oscillation, where ice from the Great Glen and Inverness Firth readvanced and deformed glaciomarine sands and silts of the Ardersier Silts Formation. At the gully section close to the car park, we were treated to spectacularly-deformed rhythmically-bedded silts, with Emrys Phillips excitedly explaining to us the deformation processes involved in push moraine formation.

Site 3 – Kingsteps

After a picnic at Ardersier and a detour through a petrol station forecourt, we arrived at Kingsteps to study the raised shorelines exposed as a set of terraces in fields below Lochloy House. Two or three terraces could be seen, which are cut by, and therefore predate the so-called ‘Main Postglacial Cliffline’, which formed during the Younger Dryas. Whilst farming activity has degraded the terraces, they are still visible, but are better preserved in the Christmas Tree plantations to the east. The raised shorelines and shingle ridges provide evidence which constrains the postglacial isostatic rebound of the area, however, some members of the trip felt that this, combined with the poorly-constrained nature of the work presented by Lambeck (1995), was too far outside of a quantifiable mean sea-level range to provide adequate evidence of punctuated RSL change, as many different permutations of a sea-level curve could be viable.

Site 4 – Easterton

A quick stop was taken at some farm buildings on top of a transverse ridge. These transverse ridges have been interpreted as crevasse-squeeze ridges. Little evidence of the typical sedimentology associated with subaqueous landforms could be seen within the Easterton section. This, combined with their altitude and their interrelationship on DEMs, led most members to agree that the landforms were more consistent with a corridor of crevasse-squeeze ridges, similar to those observed in Saskatchewan, Canada (Evans et al., 2016). Other transverse ridges occurring towards Elgin and on Tarbat Ness, to the north of the Inner Moray Firth, have been described as De Geer moraines but are in some places at 60 m above OD. These are unlikely to be glaciomarine De Geer moraines, if they are at all De Geer moraines, due to their age and elevation, unless there was a relative sea-level fall of 30m in less than 500 years (~60 mm/yr), against a background Global Mean Sea-Level rise of approximately 5 mm/year (Bassett et al., 2005).

Site 5 – Cloddymoss

Another quick stop was taken at Cloddymoss to view the distal Ardersier Silts contacting the underlying subglacial Easterton Member of Finglack Till Formation. These are the formations into which the Main Postglacial Cliffline is eroded.

Site 6 – Grange Hill

The final stop for the day was the large, flat-topped ridge surrounded by Late Devensian and Holocene marine deposits. These have previously been interpreted as chasm fill in a large crevasse (Peacock et al., 1968). However, the arcuate nature of this and the neighbouring ridges (Figure 2) are reminiscent of the Ardersier push moraine and, similar to that seen in Jamieson’s pit earlier in the day at Ardersier, is also capped by a thin orange-brown diamict. Another possible interpretation is therefore that the ridges are push moraines formed during what has been termed the Grange Hill Oscillation, formed by readvance of the Moray Firth Glacier, temporally between the Elgin Oscillation and the Ardersier Oscillation seen earlier in the day.

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Figure 2. View from the flat-topped Grange Hill, over Holocene marine deposits, to the adjacent, arcuate flat-topped ridge.

Day 2 – Saturday 28th October – Sites within the Lower Findhorn Valley, Strathnairn and Strathdearn

Site 1 – Meads of St John

Similarly to the previous day, we were fortunate to experience more glorious weather the next morning. Even more glorious were the subglacial hydrofractures through the Devonian bedrock (Figure 3). Healthy discussion was had, led by Emrys Phillips, about how such features form. Discussion of the geomechanical regime necessary to form such features was had, including the source of the overpressure required to form a hydraulic fracture, as well as the role of principle stresses and stress transference from subglacial movement causing sub-horizontal fracturing.

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Figure 3.
Complex hydraulic fracturing in Devonian Old Red Sandstone bedrock at Meads of St John.

Site 2 – Dalcharn

Driving down the unmetalled road towards Dalcharn took us from the Last Glacial Maximum all the way back into the Last Interglacial. At Dalcharn West, a series of subglacial tills underlie and overlie a palaeosol. Although the pollen record suggests a Hoxnian age (Walker et al., 1992), an infinite radiocarbon date of 41,300 BP together with maximal luminescence ages of 68 and 50 ka suggest that the palaeosol formed during the Ipswichian. Hard graft put in by a few intrepid team members removed fallen trees to uncover what remains of the palaeosol. This revealed an inverted sequence to what was originally observed, with the peaty Dalcharn Biogenic Member underlying the siltier Dalcharn Cryoturbate Member. Whether or not the formation can be considered as autochthonous and deformed or rafted in later is still uncertain. Clearly, the site has great potential to yield vast information about the longer-term palaeoclimatic and glacial history of Scotland if more work is put into unravelling its mysteries.

Site 3 – Clava

Clava is a historical locality, having been visited by such notable figures as Horne, Jamieson, Agassiz and even Charles Darwin. Their interest, and those of many authors since, had been drawn by a shelly till at 150 m above OD. The origin of these marine deposits has been debated frequently, being 110 m higher than any other known marine deposits. Most now agree that they have been ice-rafted, but explaining the mechanism by which a raft can remain relatively undeformed after being rafted up to 50 km laterally and over an hundred metres vertically is difficult. No evidence of freezing is seen in thin section, therefore Phillips and Merritt (2008) and later, yet to be published, revised models propose a mechanism of elevated fluid pressures subglacially squeezing the imbricated stack of glacitectonically rafted blocks along the base of a glacier. These duplexes were then accreted onto the side of a more resistant bedrock high as the Great Glen Glacier was forced upwards and over metamorphic bedrock. This conceptual model still has a few issues and trip members were quick to point these out, such as how little internal deformation there is without having been frozen to the bottom of the glacier, although were unable to offer further explanation without further thought. The actual presence of the shelly till was hard to determine though, as the field meeting party only found one 2 mm bivalve shell throughout the entire outcrop!

Site 4 – Flemington Eskers

With darkness encroaching, a quick final stop was made to visit the eskers and flat topped ridge at Meikle Kildrummie. The Flemington Eskers are a series of beautifully-preserved braided eskers that become a flat-topped ridge towards the east. The flat-topped ridge is proposed to be a glaciomarine delta formed subaerially at the mouth of the braided glaciofluvial esker system, and the presence of kettle holes on the ridge support this. The position of the eskers is at the approximate confluence of the Monadhliath and Great Glen ice streams, therefore these eskers were considered to have formed under the shear margin where the two ice streams met. Such an interpretation may lead to the reinterpretation of the flat-topped ridge to be an ice-walled chasm, similar to that proposed at Grange Hill, which lies further east, but on the same trend as the Flemington Eskers.

Day 3 – Sunday 29th October

Site 1 – Daless Viewpoint

The final day began with a short, steep stroll up to a fantastic viewpoint (Figure 4) over the Middle Findhorn Valley where Adrian Hall and David Jarman explained the significance of the valley in terms of the long-term denudation history of Scotland. The lack of geomorphological evidence of extensive valley glaciation and the smooth “summit surface” topography implies that cumulative glacial erosion here was not extensive, and that the Nairnshire mountain tops are close to their original height. This interpretation is backed up by the extent of weathering of the Caledonian granite, which has been severely degraded to loose sands up to a depth of 8-10 m.

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Figure 4.
David Jarman describes how big the one that got away was at Daless Viewpoint.

The glacial geomorphology of the valley is mainly glaciofluvial and glaciolacustrine in origin. Up to 14 terrace levels have been identified, mainly consisting of kame terraces but also fans and deltas. The promontory which provides the viewpoint would have provided a dam for proglacial lakes in this area. The rest of the dam was proposed by some members of the party to be consistent with observations of more dynamic ice (compared to that of the relatively stagnant, and therefore causing little erosion, ice in situ) flowing back up the valley from the south, back-filling the valley and providing further damming for proglacial lakes.

Site 2 – Banchor

The final stop for most of the party was to the banks of the River Findhorn at Banchor, where erosion has revealed a fantastic sequence of glaciofluvial and glacilacustrine sediments. The bottom of the sequence exposed beautiful climbing ripples (Figure 5) from a glaciofluvial sequence that transitions through delta bottomset gravels before muddy and sandy rhythmites are exposed from the proglacial Lake Findhorn. Occasional debris flows containing angular blocks can be seen sporadically throughout the sequence; these are thought to have been rock fall from the slopes of the surrounding hills flowing laterally into the lake. After this, we said our long goodbyes and faced our journeys home (mine was to Keyworth, 7 hours’ drive away, but others had to drive to London!)

Fig_5
Figure 5.
Climbing ripples in glaciofluvial sediments at Banchor.

Acknowledgements

I would like to take this opportunity to express my thanks on behalf of all the field meeting attendees to the organisers, Jon Merritt, Clive Auton, Emrys Phillips, Callum Firth, Adrian Hall and Martin Kirkbride, as well as the valuable discussions and contributions of all others. The trip was an undeniable success, the weather was almost perfect, the logistics ran smoothly and most of all, everybody was able to visit some fantastic glacial geomorphology and learn, discuss and debate (albeit in a friendly manner) the fascinating, sometimes enigmatic features visited. The field guide which accompanied the trip, The Quaternary Around Nairn and The Inverness Firth, is available now from the QRA field guides page on the website. I encourage you all to buy this impressive book, in which you will find far more detailed information about the field sites, as well as other references. Jon Merritt and Emrys Phillips are thanked for their comments on an earlier version of this report.

References

Bassett, S.E., Milne, G.A., Mitrovica, J.X. and Clark, P.U. 2005. Ice Sheet and Solid Earth Influences on Far-Field Sea-Level Histories. Science. 309(5736),pp.925–928.

Evans, D.J.A., Storrar, R.D. and Rea, B.R. 2016. Crevasse-squeeze ridge corridors: Diagnostic features of late-stage palaeo-ice stream activity. Geomorphology. 258,pp.40–50.

Harrison, S., Rowan, A. V, Glasser, N.F., Knight, J., Plummer, M.A. and Mills, S.C. 2014. Little Ice Age glaciers in Britain: Glacier–climate modelling in the Cairngorm Mountains. The Holocene. 24(2),pp.135–140.

Kirkbride, M., Everest, J., Benn, D., Gheorghiu, D. and Dawson, A. 2014. Late-Holocene and Younger Dryas glaciers in the northern Cairngorm Mountains, Scotland. The Holocene. 24(2),pp.141–148.

Lambeck, K. 1995. Late Devensian and Holocene shorelines of the British Isles and North Sea from models of glacio-hydro-isostatic rebound. Journal of the Geological Society. 152(3),pp.437–448.

Peacock, J.D., Berridge, N.G., Harris, A.L. and May, F. 1968. The Geology of the Elgin District, Memoir of the Geological Survey, Scotland, Sheet 95.

Phillips, E. and Merritt, J. 2008. Evidence for multiphase water-escape during rafting of shelly marine sediments at Clava, Inverness-shire, NE Scotland. Quaternary Science Reviews. 27(9–10),pp.988–1011.

Walker MJC, Merritt JW, Auton CA, Coope GR, Field MH, Heijnis H, Taylor BJ. 1992. Allt Odhar and Dalcharn: two pre-Late Devensian (Late Weichselian) sites in northern Scotland. Journal of Quaternary Science 7: 69-86.

 

Steve Farrell

I was sat enjoying a pre-field day breakfast coffee on a sunny morning in Northern Ireland when I received the email from the BSRG saying I was to be the 2018 recipient of the Steve Farrell Memorial Fund. I excitedly told the other field trip staff that I’d won funding for my EGU trip. It wasn’t until we got back that the field trip leader, our head of school Simon Bottrell, found out it was in the memory of Steve Farrell. Simon told me that he and Steve were friends during their undergrad at Oxford.

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Stephen G. Farrell, 1960 – 1987. Photo used with permission of John Underhill.

When I was in the process of applying for the memorial fund, I quickly searched for some information on Steve but found it difficult to find anything. After Simon had told me he knew Steve, it reignited my curiosity in who Steve was, and why there was a memorial set up in his name.

“I remember Steve visiting Leeds just after I arrived here very vividly,” reminisced Professor Bottrell. “This would have been about 1986, not long before he died.” I told him about how I could find very little information on who Steve was, and he pointed me to Steve’s obituary from the AAPG Bulletin (Underhill, 1987).

Steve died tragically young, just two years after finishing his PhD, but had a huge impact on our understanding of the interplay between sedimentation and tectonics in such a short time. After his undergraduate degree at Oxford, Steve moved over to Cardiff to study the Ainsa Basin marine slope sediments for his Shell-sponsored PhD. Steve published numerous papers on this work, as well as subsequent research in Cyprus as he began working for BP.

Soft-sediment slumping due to gravity is a common feature of many basins, but in his first paper (Farrell, 1984), Steve concentrated on the ones exposed in the San Vincente Formation. He applied dislocation modelling to explain the complex relationships between compressional and extensional regimes within the slumps, and investigated the origins of overprinting of extensional regimes on top of compressional regimes. These somigliana dislocation models had typically been used at a larger, tectonic scale, but Steve applied the models at the slump scale to explain the complex relationships and how they could be distinguished as gravitationally-induced, as opposed to being related to the Pyrenean orogeny. The figures drawn by Steve in this paper evocatively capture the detail and complexity of the beautiful slumps, as well as showcasing Steve’s exquisite eye for detail.

Soft sediment slumps in the Labuerda Canyon, Ainsa Basin, which Steve studied extensively for his PhD. First image shows the complexity of folding in these slumps, displaying recumbent folds. The second image shows upright folding within the same outcrop. The third image is taken from a virtual outcrop model showing both of the previous features. All images courtesy of John Howell (@Virtualgeol) and the Virtual Outcrop Geology Group.

Steve blended sedimentology and structural geology seamlessly. A master of both, Steve’s next paper (Farrell et al., 1987) concentrated on constraining the sequence of thrusting during the Pyrenean orogeny through stratigraphic relationships. By studying folding and unconformities within the piggyback basins, he unravelled the complex faulting history within the foreland. Here, he showed that instead of the classic foreland-propagating thrust sequence, thin-skinned thrusting built up the Montsec thrust and constrained the Tremp-Graus basin. The northern edges of the Tremp-Graus basin were then deformed by thick-skinned, basement thrust sheet stacking in the axial zone to the north. This particular paper is especially poignant for me because we studied this area on an MSc field trip and saw for ourselves the stunning results of faulting and folding. The structural geology out there, such as the Mediano Anticline (below), is truly awe-inspiring.

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The breathtaking Mediano Anticline, Ainsa Basin, Spanish Pyrenees.

It wasn’t just the Pyrenees that Steve studied. Whilst working for BP, Steve was involved in the development of the booming North Sea plays. But Steve also studied in the field in Cyprus, resulting in his third (Farrell and Eaton, 1987) and fourth (Farrell and Eaton, 1988) papers, both published posthumously. In his third paper, Steve explored fold geometries in soft sediment slumps observed in the Khalassa and Maroni basins in Cyprus and compared them with those observed in the Ainsa Basin. Steve unpicked the complex folding styles, often folded then refolded, to determine models of slump translation distances. The more complex the folding, the higher the shear strain, and therefore the more complex the folding. Simple shear dominates during slump translation; once the slump begins to decelerate, pure shear can occur, resulting in beautiful sheath folds and refolded folds.

Deformation of sediments is not just related to palaeoslope-induced slumping, however, and Steve recognised this in his fourth paper (Farrell and Eaton, 1988). Here, again studying with Simon Eaton, Steve deconvolved the deformation that occurred due to slumping from ptygmatic folding occurring during compaction. Overprinting of later, diagenetically or compactionally-induced fabrics often occurs to complicate the stories of soft sediment deformation.

Steve’s career promised much but was tragically cut short. Steve’s research added valuable insights into soft sediment deformation processes and their relation to the tectonic evolution of sedimentary basins, paving the way for palaeoslope analyses through basins worldwide. Much of our understanding of the stratigraphic evolution of basins under active tectonics relies on detailed investigations of outcrops, and Steve’s brilliant mind was able to unravel these. In turn, these textbook examples of sedimentary and tectonic process interaction became invaluable as teaching tools for basin evolution. During my education, Steve’s research cropped up again and again – first at undergraduate level, studying the evolution of the sedimentary basins of Cyprus during the Tertiary in response to complex tectonics, then again at Masters level, on field work in the Pyrenees, studying complex tectonic and sedimentary interactions.

Despite his illness, Steve continued to pursue both sport and science with vigour. His squash prowess endured, reaching the finals of BP’s global squash tournaments even during his illness. Steve was committed to research and science all the way, too. Even during the infamous “Christmas conference season” of BSRG and TSG, December 1986 and early January 1987, Steve refused to let his illness beat him, and attended and contributed to both conferences. Steve died from cancer on 30th January 1987.

Steve was, and still is to this day, sorely missed by those who knew him. The BSRG decided to set up the Steve Farrell Memorial Fund in his name, in order to benefit scientists with even as much as half the vigour and enthusiasm that Steve displayed. I am hugely grateful and indebted to the BSRG for awarding me the Steve Farrell Memorial Fund in 2018 to aid my attendance to the EGU General Assembly in Vienna. Here, I was able to present the results of my own research. I feel privileged to have presented in the memory of Steve, and hope that I have honoured his name in the process.

Stephen G. Farrell, 1960 – 1987.

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Slumped Carboniferous deltaic sandstones near Greenhow Hill, Yorkshire, showing similar deformation characteristics to those studied in deepwater sediments by Steve. AS well as dewatering structures, both upright and recumbent asymmetrical folds can be seen. These were induced by seismicity on the North Craven Fault, 2 km to the south.
References

Farrell, S.G. 1984. A dislocation model applied to slump structures, Ainsa Basin, South Central Pyrenees. Journal of Structural Geology. 6(6),pp.727–736.

Farrell, S.G. and Eaton, S. 1988. Foliations developed during slump deformation of Miocene marine sediments, Cyprus. Journal of Structural Geology. 10(6),pp.567–576.

Farrell, S.G. and Eaton, S. 1987. Slump strain in the Tertiary of Cyprus and the Spanish Pyrenees. Definition of palaeoslopes and models of soft-sediment deformation. Geological Society, London, Special Publications. [Online]. 29(1),pp.181–196. Available from: http://sp.lyellcollection.org/lookup/doi/10.1144/GSL.SP.1987.029.01.15.

Farrell, S.G., Williams, G.D. and Atkinson, C.D. 1987. Constraints on the age of movement of the Montsech and Cotiella Thrusts, south central Pyrenees, Spain. Journal of the Geological Society. [Online]. 144(6),pp.907–914. Available from: http://jgs.lyellcollection.org/cgi/doi/10.1144/gsjgs.144.6.0907.

Underhill, J.R. 1987. Memorial: Stephen G. Farrell (1960-1987). AAPG Bulletin. 71(7),p.901.

 

It’s been a long time coming

I set this blog up not long after starting my PhD, one and a half years ago. I did mean to write blogs, but…

Welcome to the Ancient Shorelines blog. I’m Andy and I’m a PhD student at the University of Leeds. I’m studying the landscape evolution of Dogger Bank in the North Sea.

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Location of Dogger Bank in the Southern North Sea. Bathymetry: http://portal.emodnet-bathymetry.eu/ 

During the Last Glacial Maximum (LGM), around 25,000-22,000 years before present (BP), there was an ice sheet present over much of Britain, Scandinavia and the North Sea. Subsequent sea-level rise since the LGM caused inundation of the North Sea. During this marine transgression, which began around 11,000 years BP, the coastlines changed in response to rapid sea-level rise. It’s my job to find out how the stratigraphy and sedimentary processes responded to that rapid rise.

I’ll also be looking at what the stratigraphy tells us about the processes involved in deglaciation of the ice sheet at Dogger Bank. We already know that there was a lake twice the size of Lough Neagh sat on top of Dogger Bank, but what was its role in the collapse of the Eurasian Ice Sheet?

Stay tuned for more, coming soon to a blog near you.

Andy