Humberside Geologist No. 14

 

Open Questions in East Yorkshire Geology

October 2005.

A joint meeting of the Yorkshire Geological Society and Hull Geological Society. With lectures at the University of Hull on the afternoon of Saturday 8th October 2005 starting at 2-00 pm and a field trip to some of the sites around Flamborough on the Sunday.

On March 10th, 1898, George Lamplugh gave a lecture to the Hull Geological Society entitled "Some open questions in East Yorkshire Geology". It was later published in the Society's Transactions and is now available on the Society's Website <hg149.htm> and will be re-printed in Humberside Geologist. The lecture forms the basis of this year's joint meeting of the Hull and Yorkshire Geological Societies.

How many of Lamplugh's open questions have been answered since his lecture? How many remain to be answered? And after a century of research have we found new questions to ask?

Speakers will review our progress in understanding the Speeton Clay, Chalk and Quaternary deposits around the Flamborough area. The field trip will visit some of the sites.

Abstracts -

Pete Rawson - The Speeton Clay: ‘a section that is impossible to exhaust’

It is frustrating that in his 1898 talk Lamplugh observed that "the open questions that [the Speeton clays] supply would make too long a tale for one night" so said relatively little about them! But he stressed that the Speeton section 'is impossible to exhaust'. Despite the wealth of information that has been obtained since, that statement remains as true today is it was in 1898. The transient nature of the exposures, especially of the higher beds, and the occasional sweeping clean of parts of the section means that it is continuously changing and we may still make new discoveries. We can also look at it afresh in the light of broader geological discoveries made since Lamplugh's time, such as the effects of Milankovicz astronomical cycles on sedimentation.

Lamplugh's (1889) seminal work on the subdivision of the Speeton Clay had established the main, fourfold division into the A to D beds (based on the belemnite sequence) and by 1898 he could claim that the succession from the D beds to the 'Cement Beds' (middle B) was fairly well known. But he noted in his 1898 talk that knowledge of the remaining part of the succession and its faunas remained 'indefinite'. The gaps began to be filled by Lamplugh himself, together with the local workers Danford and Stather, so that by 1924 he could suggest, in his Presidential Address to our Society, a provisional correlation with the Lower Greensand and Gault sequences of southern England. Members of the Hull Geological Society also focused on the poorly known higher beds in the 1930s and 40s. But it was not till the 1990s that good temporary exposures allowed Mitchell and Underwood to produce a detailed stratigraphy of these higher levels, though the patchiness of exposure and degree of disturbance of these beds suggests that much more remains to be gleaned.

Renewed research on the main part of the sequence was stimulated by John Neale and his research students at the University of Hull in the 1960s. This led to documentation of many of the microfaunas, and renewed investigation of the ammonite and belemnite faunas. Since then Speeton has become a key section for comparison with the offshore North Sea area - the development of an oil industry there is something that Lamplugh could not foresee but would have been fascinated with. Nor could he foresee the many non-biological methods of correlation that are so important now. For example, Milankovicz-scale cycles are recognised in parts of the section, while the belemnite guards that are so common there provide important material for isotope stratigraphy. But despite all this work, Lamplugh's comment that 'whenever there happened to be a good exposure I never failed to find some detail of the stratigraphy or some fossil which was new to me' remains as true today as it did in 1898, and that is what makes the Speeton section so fascinating.

Rory Mortimore - What have we done to the Yorkshire Chalk?

Abstract -

In March 1898 Lamplugh identified the inadequacy of information regarding the Chalk of Yorkshire as positively surprising. Despite the immense advances in knowledge in stratigraphy, linking many parts of the Yorkshire Chalk-column to a regional, national and international litho- bio- and chemo-stratigraphical framework, and the work on sedimentology, tectonics and hydrogeology, there are still some surprising inadequacies. These include explanations for the hardness of the Yorkshire Chalk, the origin of many of the marl seams and the precise relationship between the Yorkshire Chalk and the southern chalks of England at various levels.

This paper first explores some of the contributions to the advances in knowledge in stratigraphy and tectonics made by many amateur and professional geologists over last 100 years and then investigates some of the areas still to be explored, supporting Lamplugh’s observation that nothing is exhaustive or final.

Mike Horne - Open questions in East Yorkshire Geology - answers from the amateurs.

Abstract -

There is a long history of quality geological research in East Yorkshire by amateur geologists. G W Lamplugh carried out most of his research in the area as an amateur, before taking a job with the Geological Survey in 1892. He worked on three main areas of interest - the Speeton Clay, the Chalk and the Quaternary deposits around Flamborough.

The Speeton Clay continues to attract many amateur collectors and some have published papers about its fossils including Danford, Ennis and Thompson. In the 1970s Lynden Emery studied the bivalves and gastropods for an unpublished thesis.

Lamplugh provided an early lithostratigraphy of the Chalk, which was followed by Rowe's biostratigraphy. A succession of Hull Geological Society members worked on the inland exposures: D W Toyne started a survey of the Chalk pits of the Wolds and when he died in a road accident the young Ted and Willy Wright continued the work until their research was interrupted by WW2. Felix Whitham and the Hull Geological Centenary Project produced a lithostratigraphy of the whole sequence in the 1980s and 90s.

The East Riding Boulder survey recorded the erratics of the region and W S Bisat's research included an accurate survey of the Tills in the Holderness Cliffs.

As well as continuing the research on the Chalk in recent years Hull G S members have informally revived the Boulder Committee and have been investigating the Quaternary deposits around Flamborough and the 'rafts' in the Holderness boulder clays. Members have also undertaken 'rescue geology' - recording and collecting from temporary or threatened exposures.

But is amateur research now under threat? Inland exposures are being filled (including fly-tipping in RIGS), university geology departments have been closed, there is a decline in the number of geology teachers in schools and the number of students studying geology 'A' level, libraries are replacing books and periodicals with computers and Hull Museums have just "deleted" the post of Keeper of Geology and will no longer be "pro-active" in the science.  How can researchers put their important specimens and data into the public domain in the future? What can geological societies do to reverse these trends and encourage amateurs to carry out research?

(Click here for the full text of this talk)

J.A.Catt - The work of G.W.Lamplugh in understanding the Quaternary history of East Yorkshire

Abstract -

Brought up and initially employed in Bridlington, G.W.Lamplugh took an early amateur interest in local Quaternary deposits, such as the tills and erratics, the shelly Bridlington Crag, the Ipswichian interglacial raised beach at Sewerby and the Speeton Shell Bed. His understanding of the Holderness till sequence was based on Wood and Rome (1868, Quart. J. Geol. Soc. Lond. 24, 146-184), though he correctly realized that their Basement Clay included two slightly different units, which he termed the Basement and Lower Purple (the Basement and Skipsea Tills in modern nomenclature). Lamplugh’s detailed accounts of these two tills and associated deposits exposed in the cliffs on either side of Bridlington Harbour (before they were obscured by concrete sea walls) and in Filey Bay were more careful than any published in Britain or elsewhere for almost a century. Consequently they are valuable even today.

In his 1888 report on the Sewerby raised beach (Proc. Yorks. Geol & Polyt. Soc. 9, 381-392), Lamplugh tentatively identified the till exposed above the raised beach as the Lower Purple (= Skipsea), and this has been corroborated by all who have subsequently studied the exposure and analysed the till. However, in later papers (starting with Rept Brit. Ass. Adv. Sci. for 1888, published 1889, 328-338), he repeatedly asserted that this till is the Basement. Various unlikely stratigraphic reasons were given for this change of mind. However, the most probable (though unstated) reason was his conviction that there was only one Pleistocene glaciation in Britain, implying that the beach was ‘preglacial’ and not interglacial. In view of the widespread evidence for several glaciations and numerous interglacials in the British Quaternary sequence, Lamplugh’s monoglacialist views are now untenable. Also in 1963 temporary shore exposures between Sewerby and Bridlington showed that the Basement Till underlies the Sewerby interglacial beach and later deposits (Marine Isotope Stages 5e and 2), and is therefore attributable to MIS 6 (Late Wolstonian) or an earlier glaciation.

(Click here for the full text of this talk)

Displays -

"Belemnites from a raft of Oxford Clay found on the Holderness Coast" by Stuart Jones.

"Squat Lobster from the Speeton Clay" by Dave Turner.

"Fossils from the Tealby series and chalk succession of North Lincolnshire " by John Green.

Abstract - "Investigations I have made into small but important exposures of the latest Jurassic and earliest Cretaceous, Spilsby and Claxby beds of Lincolnshire in recent years have revealed a large and varied fauna, these faunas are of special significance largely due to the fact that large scale exposures of these beds are no longer available and those that are almost inaccessible.The display will include a selection of the aforementioned fauna and also a range of fossils from the chalk of North Lincolnshire I have been collecting fossils for 13 years and predominately specialise in the Tealby series and the chalk of North Lincolnshire, I would gladly welcome feedback or questions from other members and would be keen to view specimens from either area."

"A Tertiary bivalve from the Holderness Tills" by Mike Horne.

"Some Lamplugh correspondence" by Jack Doyle.

"Microfossils from the Chalk, Speeton Clay and Quaternary of East Yorkshire" by Mike Horne.

"Glacial erratics from the Wolds plateau" by Derek Gobbitt.

"Erratics from the Yorkshire Coast from Whitby to Easington" by Ron Harrison.

Back numbers of Humberside Geologist will be on sale.

"Living fossils and plant fossils" by Gordon Binns and Chris Blackhurst.

"Fossils from the Lincolnshire Chalk" by Paul Hildreth

A CD-ROM containing photographs of the field trip and displays, recordings and texts of the lectures is now available . Please contact the Secretary to order a copy.

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