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Copyright Hull Geological Society.

(updated 20th March 2019)

Ian Heppenstall died of a heart attack on 9th March 2019, aged 72. His funeral will be in the small chapel at Chanterlands Avenue Crematorium at 1pm on Monday 25th March. A collection will be made for Parkinson’s Disease.

Whitham Medal 2019-

The Felix Whitham Memorial Medal is awarded to Lewis Rose for his contribution to the understanding of local geology through the new Geology displays at Hornsea Museum. The medal is awarded “for contributions to new research into the geology of eastern Yorkshire or northern Lincolnshire, or it may be awarded for active contributions to geological outreach projects in the Hull area…."

Thursday 28th March 2019 - Dr Lyndsey Fox of Hull University on "Illuminating Anthropogenic climate change with 150 years of ocean science"

Abstract -

"Modern oceanography began with the HMS Challenger expedition from 1872 to 1876. This historic voyage was the first to specifically gather data on a wide range of ocean features, including ocean temperatures, seawater chemistry, currents, marine life and the geology of the sea floor. With the 150th anniversary of this momentous voyage fast approaching (2022), I aim to take the historical endeavours of this seminal expedition and combine them with 21st century cutting-edge science to tackle some of the most urgent questions of our time with regards to anthropogenic environmental change. The vast quantities of Challenger plankton tow material housed in the Natural History museum collections offers a singular opportunity to spotlight one of our most pressing environmental issues: ocean acidification (OA).

"Both measured and projected changes in seawater chemistry have potentially catastrophic biotic effects as OA hinders biogenic carbonate production, leading to substantial changes in marine ecosystems. Current attempts to address this issue via laboratory based studies have serious limitations, which can only be overcome by comparing newly discovered plankton tows from the historic HMS Challenger expedition (1872-1876) with the ground-breaking TARA expeditions (2009-2016). 

"Here we discuss the untapped potential of historical collections for gaining new insights into the sensitivity of the global climate system to CO2 forcing, as we present new data gathered over the past 12 months from two test sites in the tropical Pacific Ocean. These data revealed, without exception, that of the 24 specimens analysed through nanno-CT scanning; all modern foraminifera showed significantly thinner shells compared to their preindustrial counterparts (Figs. 1-3). Open ocean studies, such as this, are urgently needed to understand the impact of multi-stressor environments on shell parameters of multiple species, and reveal the magnitude of OA across the globe."

Thursday 21st March  - Evening Lecture - Prof David Bond of Hull University on "When life nearly died - new perspectives on the Permian-Triassic mass extinction" and "Ediacaran-like textured organic surfaces: microbial mats thrived after the Permian-Triassic mass extinction" with displays.

David Bond

Abstracts -

"When life nearly died - new perspectives on the Permian-Triassic mass extinction"

At the end of the Permian, 252 million years (Myr) ago, Earth suffered its greatest ever crisis during which around 90% of living species were wiped out. Almost every group was affected, on land, and in the oceans, and it is the only mass extinction of insects. This truly was "the day the Earth nearly died" (although it lasted significantly longer than a day!). This was an event so catastrophic that it wiped the evolutionary slate clean, ultimately paving the way for the rise of the dinosaurs (and then, of course, humans). But what could possibly have caused such a disaster?

 

Despite controversy over the timing of losses, radio-isotopic dating indicates that extensive damage was done to both terrestrial and marine ecosystems in a very brief interval around the end of the period. The focus now is on understanding the role of the proposed kill mechanisms, including (in no particular order): global warming, ocean anoxia (deoxygenation) and acidification, volcanic winter, hypercapnia (CO2 poisoning), aridity on land, increased sediment flux to the oceans, ozone destruction and resultant harmful ultraviolet-B radiation, acid rain, atmospheric oxygen depletion, and poisoning by toxic trace metals. Each has probable origins in Siberian Traps volcanism, in particular the vast volumes of gases (e.g. CO2) that must have been released. The latest work is beginning to reveal the likeliest culprits: extreme global warming and its knock-on effects, perhaps coupled with an acidification crisis in the oceans.

"Ediacaran-like textured organic surfaces: microbial mats thrived after the Permian-Triassic mass extinction"

Lower Triassic marine strata of the Sverdrup Basin (Arctic Canada) include a thick succession of sandy and silty facies that record life in the aftermath of the end Permian mass extinction. Proxies for oxygenation (trace metals, pyrite framboids) suggest that dysoxic conditions prevailed in the Basin for much of the Early Triassic. This suppressed bioturbation and allowed the frequent development of microbially-induced sedimentary structures (MISS), including wrinkle structures, Kinneyia and bubble texture. The microbial mats responsible for these structures are envisaged to have thrived, in dysoxic settings, within the photic zone, on fine sand substrates. The dysoxic history was punctuated by better-oxygenated phases, which coincide with the loss of MISS. Thus, Permo-Triassic boundary and Griesbachian mudrocks from the deepest-water settings have common benthos and a well-developed, tiered burrow profile dominated by Phycosiphon. MISS are also lacking from Skolithos-burrowed, nearshore sandstones that developed during basin-wide oxygenation in the late Dienerian. Intervals of the intense burrowing in the earliest Triassic contradicts the notion that bioturbation was severely suppressed at this time due to extinction losses at the end of the Permian.

 

Thursday 21st February 2019  - Evening Lecture  - Prof Chris Clark of Sheffield University on the "Retreat of the last British-Irish Ice Sheet "

Abstract –

We have known for a long time that a kilometres-thick ice sheet largely covered Britain and Ireland during the last glacial, peaking at around 27,000 years ago. Most evidence for its geometry arises from tens of thousands of geological and geomorphological observations, but almost wholly restricted to land. The earliest researchers (e.g. Geike 1867) were happy to use simple glaciological logic (presumed ice sheet symmetry) to reconstruct ice margins that reached far offshore and to the continental shelf edge. Such views were rejected by more conservative and evidence-based approaches that followed, leading to reconstructions of a mostly terrestrially-restricted ice sheet. Numerical ice sheet models of the time did what they were told regarding ice limits. Over the last decade the focus of investigation has moved offshore, enabled by new high resolution bathymetric and shallow seismic data, and leading to a ‘gold-rush’ of discoveries that have transformed our understanding. The continental shelf has abundant evidence of grounded ice cover.

 

The BRITICE-CHRONO consortium of researchers has been a six year project to constrain the timing of retreat of the British-Irish Ice Sheet by a systematic dating programme focussed on the marine-to-terrestrial transition. From two research cruises some 18,000 km of geophysical data and 377 vibro- and piston cores, along with many stratigraphic sections on land have been used to provide material for dating. The aims and objectives of the project and progress thus far will be reported along with some highlights from the various transects under investigation. The new BRITICE Glacial map of Britain and Ireland will be shown which contains some 170,000 glacial landforms.

 

A unique piece of geo-art is for sale. For the "On the Endless Here" collaboration between local artists and members of the Society, Anna Kirk-Smith created a piece called “With a Learner’s Faith”. Anna is now moving to a smaller studio in Bridlington and would like to sell the work to a interested geologist rather than auction it. If you would like to make an offer please email the HGS Secretary.

“With a Learner’s Faith”

Anna describes the work -

This painting / construct was part of the On the Endless Here show;  the accompanying description is below. It is on MDF / wooden frame with a painted/drawn surface and 3D objects/fossils. It is quite large - approx. A1 in size.

This once was how the George Lamplugh described his approach to his studies of the Pleistocene tills and fossils at Bridlington Crag, including Danes Dyke, South Landing and Sewerby, my initial stomping grounds. He began his field observations in 1878, at the tender age of 19 years and was a descriptive genius. I put my “learners faith” (utterly devoid of genius) in the Hull Geological Society and began the exploratory field trips with the members to the headland (sagely noting the white stone,  and overlying brown ooze), beyond that observation in these initial days they could have been talking a foreign language. My early field book notes consist of a list of geological jargon with question marks beside them (for later looking-up in a dictionary), and copied (thankfully idiot-proof) diagrams that Mike Horne drew in the sand with his umbrella to explain the surroundings. Initially it didn’t help that this was a questionable landscape – I was trying to comprehend the unknown, the hypothesized, about a terrain that just kept throwing geological curveballs. However once I had settled into the frame of mind that 2+2 might equal 4, 5 or indeed any other random integer potentially proven or disproven by sampling; I became less worried by predetermined fact and more intent upon potential areas of enquiry.

After 2 years of field visits, gone to me  is the visually nice white chalk topped with that ooze of brown mud; and an appreciation has appeared of forensic searching for biostratigraphical fossils, posing reasons for folding and faulting, descriptions of marl content, determining the age and colour of till samples, magnifying grains of sand to distinguish the processes they have undergone, pondering the far flung origins of glacial erratics and weaving predictions around the size, sorting, orientation, shape and turbation of chalk clasts. Within these lay the foundation for the headland’s narrative probability.

So this particular artwork sprang from that empathy with Lamplugh’s initial search of an unexplored, misunderstood terrain. He possessed far more knowledge than I when he studied the headland, so as a complete initiate, I have in the artwork reverted to a primary Victorian method of learning: the ABC, and added a flavour of my research, queries, field notes and visual perceptions I had to forage for in order to try and understand some of the geological riddle of Flamborough."

Click here for the On the Endless Here Facebook page. There is also an OTEH website projects page on www.annakirksmith.com

 

Thursday 17th January 2019 - Evening lecture - Dr. Michael Oates on "Exploring Morocco's Palaeontological Riches".

Michael Oates

The speaker on a heavily dug hillside of Devonian mudstone near Tazoulait

Abstract - The southeastern part of Morocco lies within the limits of the Sahara Desert and is an arid desolate, scarcely inhabited environment, with an undulating eroded basement of folded Palaeozoic sediments beneath an unconformable cover of horizontal Cretaceous deposits.  The common theme to all these sediments is that they have suffered relatively little structural or thermal modification and are very fossiliferous.  An overland expedition in early 2018 examined the geology in three areas of southeast Morocco, near Taouz, Alnif and Goulmima, which is just at the margin of the Atlas mountains.  Because the African continent has remained fairly stable throughout Phanerozoic time, there has been less burial than might be expected, and the preservation of the fossils is correspondingly excellent.  Expect to hear about Ordovician trilobites in abundance, a surprise Silurian limestone with 3D graptolites, Devonian shelf faunas and Upper Cretaceous freshwater to marine fossils, and how they are found.  Without the restrictions of a 20kg airline baggage allowance, as many specimens as I can carry will be available to view on the night.

ammonite miners

Ammonite, Fish and Reptile miners of Asfla

 

Thursday 6th December 2018 -  Paul Hildreth on "Women in Geology"

P Hildreth lecture

Abstract -  “This talk was inspired by a meeting of the Yorkshire Geological Society, “Leading Yorkshire Figures in the History of Geology” in 2017 which featured many individuals but none of them women.  A little research into women geologists generally revealed that there had been outstanding contributions and that their achievements, more often than not, had been against the odds.  In more recent years several women stood out despite them working in a male-dominated branch of the sciences. 

 “The early female scientists had a number of common characteristics. They were often born into influential families, which allowed some women to work voluntarily, for no pay and usually no status, because they had a private income or were supported by a man.  It was common for male scientists to have female assistants, and the well-known male geologists of the time encouraged women to do some of the time-consuming work of writing and illustrating. These women often went unacknowledged and become lost to history. There were 24 women geologists in the 100 years of the 19th Century but none with formal training prior to 1890.

 “As a matter of delicacy I had not considered extant female geologists, though there would be several candidates for inclusion, until one was a guest on Radio 4’s “Desert Island Discs” in September 2017.  This immediately, at least in my mind, promoted her to the “inner circle” that I shall present.”

November 2018 (postponed) -  Dr Eddie Dempsey of Hull University on "The Great Glen Fault Zone - Back and forth for longer than we thought"

E Dempsey lecture

Abstract - " Deformation in the upper crust during orogenesis is often characterised by the reactivation of pre-existing structures. Unravelling the early deformation history of such structures such as the Great Glen Fault Zone (GGFZ) is generally problematic due to overprinting by subsequent events. While the Devonian to Oligocene movements of the GGFZ are well documented, the earliest deformations associated with this fault remain contentious with both sinistral and dextral early movements proposed. The GGFZ consists of a poorly exposed ̴ 300m wide intensely deformed fault core and a series of parallel synthetic high angle strike-slip faults. One such parallel structure is the Rubha na h-Earba Fault sits approx. 300m from the inferred GGFZ core and is exposed on the North shore of Loch Linnhe at Kilmalieu. Due to its proximity to the GGFZ it is reasonable to assume a common deformation history. Field analysis reveals, four distinct high angle fracture sets; Group 1 (ENE/WSW); Group 2 (N/S) and; Group 3 (NW/SE) and; Group 4 (NE/SW).Group 1 are associated with green cataclasites, slickenlines and R-shears. They predate the deposition of the overlying lower Devonian Rubha Na h-Earba Sandstone Formation. These are the earliest recognised GGFZ related structure and display dextral shears sense and are consistent with dextral motion of the Rubhba na h-Earba Fault within the GGFZ. Group 2 structures are associated with widespread brecciation and oxidation of the fault rock and are regularly seen to cross cut the Group 1 structures. Shear sense indicators (R-shears, oversteps, jogs, and offsets) are typically sinistral and are consistent with sinistral motion of the Rubha na h-Earba Fault. Group 3 are associated with minor calcite mineralization and camponite-monchiquite dykes emplaced during Permo-carboniferous dextral motion of the GGFZ. These structures regularly overprint groups 1 and 2 (locally reactivate group 2) and are predominantly tensile or dextral. Finally, Group 4 strike parallel to the Rubha na h-Earba Fault are heavily brecciated with cataclasites present. Shear sense indicators associated with these structures are mostly sinistral but dextral motions are common suggesting a complex reactivation history. Stress inversion, slip and dilation tendency modelling indicate that the Group 1 structures may have resulted from a regional stress regime consistent with E/W Scandian compression. This raises the intriguing possibility that the GGFZ formed as a Scandian transform fault at the southern end of the Moine Thrust Zone." We hope to reschedule this talk in 2019

At the Annual General Meeting in 2018 the following policies were adopted -

Thursday 15th March 2018 - Dr Katie Strang on "Urban geology: buildings rock!"

Abstract - Stone is one of our most important natural resources here in the UK and the local stone has provided a source of high quality, versatile and durable building material. Scotland has one of the richest legacies of traditional (pre-1919) buildings and other stone structures of any country in the world and the most common types of building stones are directly influenced by the areas underlying local geology. In Glasgow, many of the stone buildings were built in the second part of the 19th century and are now some of the stonework is showing signs of decay and calls for repair. Years of accumulation of air pollution from industry and domestic coal burning through much of the 20th century has accelerated stone decay in many parts of the city. Furthermore, inappropriate repairs have resulted in worsening of the problem. This talk will outline the most common building stones in Scotland and the North of England and the important physical properties of these building stones, and the importance in choosing a suitable replacement in building conservation.

Thursday 25th January 2018 - Dr Liam Herringshaw of Hull University "Burrowing Through Time".

Abstract - "My plan in this talk is to try and explain why burrowing worms are amongst the most important creatures on Earth (something that Darwin first realised), why they were crucial to the Cambrian Explosion of life on Earth, and also how fossilized burrows can affect the properties of economically important rocks, from oil and gas reservoirs to aquifers (not to mention shales that might be fracked). Last but not least, I will introduce the strange science of ichnology, and its even stranger practitioners, including the Oxford professor who made tortoises walk on pie dough."

Prof. John Catt died on 7th December 2017. John had been a member of the Society since 2006. He had been associated with Hull and Holderness for a long time; studying for his PhD with Lewis Penny at the University and writing extensively about the Quaternary ice ages in the region.

Thursday 14th December 2017 - Ian Heppenstall on "Grassington, Lea Green to Conniston Dib"

Abstract - The area to the north of Grassington including Grass and Bastow Woods, Lea Green, Kimpergill, White Nook Dib, the Old Pasture and concluding with Conistone Dib contain a wealth of glacio-karst features, numerous Bronze and Iron Age remains and, from a more recent period are crossed by a maze of lead workings. Large parts of these areas were cleared of trees at an early period and unlike many other places the monks of Fountains, or any other abbey were only allowed limited access. The dip of the limestone gives rise to a secondary valley formation high above and 'parallel' to the main valley of Wharfedale but still part of it with Conistone Old Pasture forming a high ridge between them. Other high features can be seen in the raised valley before the ground rises again towards the alternating layers of gritstones and limestones of Grassington Moor to the east of both Conistone and Grassington where, once again, many lead workings are to be found. All in all this is a most fascinating part of Higher Wharfedale. 

Thursday 9th November 2017 - Dr Rob Newton of Leeds University on  "The early Toarcian (Jurassic) oceanic anoxic event: untangling global and regional signals."

Abstract - The fascinating early Toarcian oceanic anoxic event in the early Jurassic is spectacularly represented at multiple locations on the north Yorkshire coast by the Jet Rock. This is an organic rich laminated shale that is thought to represent the local expression of a widespread depletion of oxygen in the worlds’ oceans. The sediments deposited in Yorkshire were laid down in shallow sea that covered a large portion of Europe and much of the work on this event has been conducted on rocks from this broad region. Such extensive shallow seas are a common feature of the ancient Earth but are much less extensive today.  Here I will outline some of the key evidence for changes in the Earth’s climate, weathering regime and ocean chemistry at this time, and show how we might be able to distinguish which parts of this evidence truly relate to global changes and which are more likely to relate to the poorly understood workings of these extensive shallow seas. 

Malcolm Fry died on 19th June 2017 - Paul Hildreth has written an obituary

19th October 2017  - Professor Patrick Boylan: Geological Sites on the World Heritage List.

Abstract -

In 1972 the United Nations Scientific, Educational and Cultural Organisation (UNESCO) adopted the World Heritage Convention, which aims to promote and support the conservation of the world’s cultural and natural heritage.  This can be considered one of the world’s most successful international treaties in any field, as it has now been adopted by 193 States (and through them perhaps at least 30 subsidiary self-governing territories in addition). Though the original primary aim was that States adopting the Convention would adopt and implement national policies that would protect all aspects and levels of their national  heritage, it must be admitted that its runaway success has been the secondary aim of establishing a World Heritage List identifying site and monuments etc. considered to of the highest universal value and significance to the whole of humanity.  

Nominations for Inscription on the World Heritage List can only be made by States Parties, and these are then evaluated and voted on by an elected World Heritage Committee. However, in practice many States tend to prioritise their major national heritage resources with the aim of gaining additional international recognition and - increasingly - tourism numbers. 

Disappointingly, though geological interest and importance is one of the major criteria for inscription on the World Heritage List, in practice reatively few sites have been Inscribed wholly or partly because of their geological or geomorphological importance, (just 86 out of the 1052 World Heritage sites ). Further, the present list of geological inscriptions is very uneven and unrepresentative of geological periods and Earth processes, and localities of key significance in the history of geology are almost absent.

Biography -

Patrick Boylan, a Past President and Honorary Member of the Hull Geological Society and Professor Emeritus of Heritage Policy and Management at City University of London, was for many years an adviser   on museums, heritage and conservation to UNESCO, including the World Heritage Committee, and over the past forty years he has visited personally a significant proportion of the natural and cultural sites and monuments now on the World Heritage List.   In this illustrated lecture he will outline not just the operation of the Convention, but also the geological interest and significance of many of the geological sites on the List. 

 

Thursday 16th February 2017 -  Dr Mike Widowson of Hull University "Divining the Deccan: Tectonics, stratigraphy, timing and effects of a major Large Igneous Province (LIP)"

Mike Widdowson

Abstract

Since publication of the milestone paper by Alvarez et al.1, the Cretaceous – Tertiary boundary (KTB) mass extinction has generally been considered the result of the Chicxulub impact and its attending environmental effects; a view reinforced by the recent contribution by Schulte et al.2. The main alternative hypothesis, Deccan volcanism, has often been regarded with more scepticism. However, in the decades since Alvarez et al., considerable research effort has been directed toward understanding the nature of the environmental change deriving from both scenarios, and determining the wider global context immediately prior to, at, and after the KTB. Accordingly, the body of scientific evidence, analytical techniques, and the understanding of key KTB sections in and around the in the world are now sufficiently mature to allow renewed debate concerning the causes and origin of environmental change at the KTB. In the case of the Deccan, this effort has relied on palaeomagnetism3, geochronology, volcanology4, stratigraphy5 and palaeontology.

 Numerous studies have found significant correlation of timing of mass extinction events with that of continental flood basalt (CFB) eruptions, thus suggesting a possible cause-and-effect. The two commonly cited CFB – extinction scenarios are the Siberian Traps - Late Permian extinction, and the Deccan – KTB extinction.  However, to explore the robustness of such relationships requires both detailed understanding of CFB volcanology and lava stratigraphies, and the application of high precision dating. The aim of this research talk is to explore these approaches, and establish what it is we currently know about the Deccan.

 Previous dating studies of the Deccan Traps, India, have concentrated upon classic sections exposed along the Western Ghats escarpment. These have provided insight regarding the timing and duration of the CFB, and indicate a geologically rapid eruption near to, and across the KTB. However, whilst these sections provide access to key parts of the Deccan succession, they do not provide a complete chronological record of the eruptions. Rather, it is the well-established stratigraphical architecture of the Deccan CFB that has offered the framework for a comprehensive sampling programme. 40Ar/39Ar dating of the basal lavas reveal late Maastrictian ages (66.7 0.5 Ma), and indicate that the volcanism began in the north-western region c. 1 – 2 Ma before the KTB. The Deccan eruptions reached their acme during Chron 29R, with successively younger lava fields building on the southern flank of an evolving Deccan volcanic edifice. The final Deccan eruptions are thus preserved in the south-western Deccan (63.7 0.3 Ma), and form the upper part of the widespread and volumetrically significant Wai Subgroup which was erupted across the KTB5,6. These age data demonstrate a duration of at least 2 – 3 Ma for the Deccan CFBP and, when combined with the associated physical volcanology, are significant because they place constraints upon the timing and efficacy of Deccan eruptions as a cause of Cretaceous global environmental deterioration.

 1.     Alvarez, L.W., Alvarez, W., Asaro, F., and Michel, A.V. (1980) Science, 208 (no.4448), 1095-1108.

2.     Schulte et al. (2010) Science 327 (no. 5970), 1214-1218.

3.     Chenet, A.L., et al. (2008), Journal of Geophysical Research., 113, B04101, doi:10.1029/2006JB004635.

4.     Self, S., Widdowson, M., Thordarson, T. and Jay, A.E. (2006) Earth and Planetary Science Letters, 248, 517 - 531.

5.     Jay, A.E. and Widdowson, M. (2008)  Journal of the Geological Society of London, 165, 177-188.

6.     Hooper, P.R., Widdowson, M. and Kelley, S.P. (2010) Geology 38(9), 839-842.

 

Thursday 15th December 2016 -  Dr Anna Bird of Hull University on “Metamorphism of the Caledonides of Scotland, deformation of a mountain belt”

Anna Bird

ABSTRACT - The Caledonian Orogeny represents the closure of the Iapetus Ocean and Caledonian orogenic events in northern Scotland are traditionally interpreted in terms of two separate orogenic events: an early Ordovician (~ 470-465 Ma, Grampian) arc-continent collision, followed by Silurian (~ 435 – 425 Ma, Scandian) continent-continent collision of eastern Laurentian and Baltica.  These events overprint the effects of much earlier mid-Neoproterozoic (Knoydartian) orogenesis representing the closure of a much older ocean basin.  Dating metamorphic minerals is one method of establishing when deformation events occurred and are useful in helping to establish how long it took these ocean basins to close. Many garnets from many different lithologies from the Highlands have Scotland have been dated.  New dates show that there is also a 450 Ma deformation event within the Caledonian Orogeny. The ages obtained throw further light on the timing of orogenic events and indicate a more complex Caledonian history than hitherto suspected.  New Neoproterozoic ages show that this area has been affect by early two stages of deformation, a much more widespread Knoydartian event, and ages, ranging from 947-748 Ma, which may be correlated with the an earlier orogenic event (980-910 Ma) recorded in East Greenland. These dates suggests that it may have taken almost 100 Ma to close the Iapetus ocean and the Neoproterozoic ocean basin appears to have taken even longer or perhaps closed in several stages.

Thursday 19th January 2017 - Ian Heppenstall on "the Geology along the north and middle Craven Faults between Malham and Threshfield".

I Heppenstall

Abstract - Near Malham the North and Middle Craven Faults begin to converge, being at their closest in Threshfield . Parts of their courses are indistinct but across Threshfield Malham Moor and Threshfield Moor they show up very plainly, whilst there are other geological, archaeological and historic features around and adjacent to them. By means of maps and photographs I will show and explain these features.

 

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Copyright - Hull Geological Society 2019

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