Newsletter of the Geological Society of Norfolk
Please note our new web site address that will be set up soon –
www.norfolkgeology.co.uk
Number 55, September 2002
There have been no changes to the Current Committee. Please refer back to a previous Newsletter if you need to know who and where we are.
News!…
New meteorite impact crater found in the North Sea off the Yorkshire coast.
A recent report on the BBC’s Science/Nature web page, (that also made it onto the TV and radio a couple of months back), reports that an ancient impact crater has been discovered 130km east of the Yorkshire coast. The crater is a 3km deep feature now referred to as the “Silverpit crater” and was created by the impact of a meteor some 120m in diameter travelling at an estimated 30km per second. The meteor impacted some 60-65 million years ago, (that’s the best date they are able to offer thus far, so it was not the coup-de-grace that finished off the dinosaurs), and would have created an enormous tsunami. The structure was originally discovered by oil geologists using seismic data back in 1992, but was not identified as a crater until it was seen by a structural geologist, Dr. Simon Stewart, who walked past a poster of the structure pinned up in the Aberdeen office of the structure’s discoverers, with the caption “anybody seen anything like this?” Though now deeply buried, the concentric fracture pattern and central peaked cone clinched the identification. [PW]
Low Cost Books……
The Palaeontological Association, (Pal. Ass.), has just published a new set of field guides to fossils, at least one of which will be of interest to members in the Eastern counties. They are also holding a sale of back issues of its Special Papers in Palaeontology (SPIP) series. The Pal. Ass. offers substantial discounts to its members on both items. These are great enough to be worth joining the Pal. Ass. (£28p.a.) if you really wanted sufficient of the discounted SPIP. The single copy of Cretaceous fossil vertebrates, (of which more later), I bought for £20 normally costs £50! The Pal. Ass. also produce newsletters approximately quarterly that contain book reviews, discussion papers, minutes of conferences arranged by the Pal. Ass. or one of its sister organisations, adverts for other conferences by the same, and some fairly heated correspondence on issues that different readers hold varying opinions on, (e.g. the value of cladistic analyses). Actually, it’s almost worth joining the Association just to get these! See Book Reviews below. [PW]
Some Papers Published Recently Relevant to the Geology of East Anglia, but not reviewed in this newsletter, are……..
Brand, D., Booth, S.J., Rose, J. 2002. Late Devensian glaciation, ice-dammed lake and river diversion, Stiffkey, north Norfolk, England.
Proceedings of the Yorkshire Geological Society, 54, 35-46.
Whiteman, C.A. 2002. Implications of a Middle Pleistocene Ice-Wedge cast at Trimingham, Norfolk, eastern England. Permafrost and Periglacial Processes,13, 163-170.
A wedge exposed at Trimingham, northeast Norfolk, UK, in 1998 is interpreted as an ice-wedge pseudomorph indicating that permafrost was present in the surrounding Cromer Forest-bed Formation sediments. The North Sea Drift Formation (NSDF) glacial sediments overlie the wedge, demonstrating that the associated ice sheet deposited till in either a terrestrial or an extremely shallow glaciolucustrine/marine environment. This conclusion supports those who believe that this ice sheet was, at least initially, terrestrial at this location.
Candy, I, 2002, Formation of a rhizogenic calcrete during a glacial stage (OIS 12): its palaeoenvironmental and stratigraphic significance, Proc. Geol. Assoc., 113, 259-270
Note that the above papers are only those that have recently come to the notice of one or more members and thus the list is not necessarily comprehensive.
Book Reviews……
Fossils of the Chalk, (2nd Edition), 2002, ed. by A.B. Smith and D.J. Batten £14, discounted to Pal. Ass. members: £10
I bought the first edition of this book when it was published in 1984. This version is enlarged, (about another 70 pages), and now includes a substantial introduction on chalk sedimentology, trace fossils, faunal provinces, stratigraphy and ongoing stratigraphical problems, (East Anglia sits as a member of the “Transitional Province” between the now reasonably well defined Southern and Northern Provinces, but is not explicitly discussed as such). The text now contains chapters relating to corals, serpulids and nautiloids. Many of the names that were applied previously to the faunas have been updated but since this is an ongoing process it can never be completely up to date in this respect. Contrarily, some names have been changed, and I should know who was responsible for altering them, but don’t! The belated inclusion of a chapter on serpulids is especially welcome as these are a very important component of some “Norwich Chalk” facies. The provision of a chapter on corals is welcome though the nomenclature applied is, as the author of the chapter freely admits, liable to future amendment. This book is then a “must have” for anyone wanting a good, up-to-date introduction to the Chalk. [PW]
Dinosaurs of the Isle of Wight, 2001 eds. David M. Martill and Darren Naish, £16, Pal. Ass. members £11
Well, okay, so Norfolk’s a long way from the Isle of Wight, but who could resist a good, up-to-date, comprehensive, well-written book that described the geology of a specific location, its dinosaur fauna, provided biographical backgrounds on famous collectors and their collections, a good identification key, and a suggested itinerary for anyone visiting the Isle with a view to doing some geology? I couldn’t! The book is absolutely excellent, a truly well-integrated account; I can recommend it unreservedly to anyone thinking about going on holiday to “southern parts”, or who simply enjoys reading about these fossils. Guaranteed not to disappoint. [PW]
Special Papers in Palaeontology: 60. The Palaeontological Society
Cretaceous fossil vertebrates
This paper is a mixed bag of 9 contributions by 18 authors and covers a wide range of taxonomic groups including sharks, a fish, a lizard, a snake, reptiles, crocodiles, an ankylosaur and a fossil track-way of an iguanodont from many locations around the world. The standard is, as you would expect from papers in this series, very high. However, unless you have a special interest in such a diverse group of animals, bearing in mind that it does not focus on just one group, tightly defined horizon or geographic location it will be of limited use to you. The Pal. Ass. is currently offering discounts on papers from this series to its members, (some 68 different titles in all). If you think that a particular volume might make a useful contribution to your research library then by all means purchase it, but ensure that you establish what topic or topics it cover first or you could be making an expensive mistake.
Provisional List of Field Meetings for 2003
Here is a “taster” of what is being planned. Exact dates will follow with full list of locations ready for the next Newsletter.
1. Field Trip to Shropshire, Sat (late afternoon), Sun (all day), Mon (all day). If anybody is interested please contact Mr. I.J. Cruickshanks 01502 724736
2. Bullcamp, Suffolk: Red Crag, Excavating a new area that has previously never been examined.
3. Harwich Foreshore, March/April Saturday Afternoon at 2.00pm
4. Aggregate Industries, Podehole Quarry. Caister St Edmund Quarry, Early July 2003, an evening.
5. Frimstone Pit, awaiting confirmation.
6. Joint trip being arranged with Stamford group, looking at the Oxford Clay
7. Upware?
8. Whitlingham Pit, leader Paul Whittlesea
Contact our Field Secretary at or 01502 724736 if you would like to know more.
Please note that the Geological Society of Norfolk has Public Liability insurance cover for field trips and other events. However, participants attend at their own risk and Personal Accident cover is their own responsibility.
Report of Field Trip at Happisburgh, 7th September.
In brilliant sunshine Jonathon Lee led an enthusiastic group of GSN members to see the exposures at Happisburgh. Some of us were late but Jon was patient and apparently forgiving!
The exposures south of Happisburgh are relatively new, being recently exposed.
We inspected the exposures in chronological order starting with a Cromerian (pre-glacial river deposit) on the foreshore. Here we could see significant evidence of wood and plant remains known to be Norway Spruce, Birch, and freshwater plants and animal bones. Courtesy of Dr Robins, late president of NNAS, we were treated to an inspection of the hand-axe found here in situ in 2000 by a man walking his dog! This is the earliest evidence of Man in Norfolk. These finds may push the date for earliest human settlement in Britain as far back as before 600,000 BP!
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In the base of the cliff is the lower till (Happisburgh Till) of what is now designated by the BGS and Royal Holloway as the Happisburgh Formation. At the top of this Till are excellent examples of crevasse-fill ridges consistent with thinning ice following a surge of the glacier. It is separated from the overlying Corton Till in the same formation by the Happisburgh clays obviously deposited into a lake, with excellent mud-draped ripples etc. The Corton Till is, in turn, overlain by the Corton sands, the uppermost unit of this formation; it is interpreted as consisting of foreset beds of a glaciolucustrine delta.
Finally at the southern end of the traverse is the Walcott Till, which is correlated with the Lowestoft Formation because of its obviously similar lithology.
The Happisburgh Formation and the Lowestoft Formation are considered to be distinct to the extent that they were deposited in separate glaciations, only the latter being laid down during the Anglian Glaciation.
Altogether this was a refreshing break from the usual story of glaciotectonics usually experienced in field trips devoted to glacial deposits! The section currently exposed is excellent.
For a more complete understanding of recent advances in the understanding of glaciation in East Anglia come to Jon. Lee’s lecture in November! [ET]
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Upcoming Lectures………
In order to reduce costs and to allow access to better parking facilities the venue for future meetings has been changed.
For an experimental period meetings will be held in the Friends Meeting House on Upper Goat Lane, just off St. Giles Street, Norwich.
There are no significant parking sites at the Meeting House itself but the multi-storey car park next door (entrance on St. Giles Street), now open during the evening, is very convenient. There are usually more free spaces here during the evenings than near the Assembly Rooms, where there is competition from other events in the Assembly Rooms and the nearby Theatre Royal. Note that all lecturers this year are members of GSN!
Thursday, 10th October. Jan Alexander, UEA 7:30 pm Friends Meeting House
President’s Lecture
Sedimentation in extreme events: consequences of major floods
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Large floods are commonly in the news and extreme floods are the stuff of folk law. A person's perspective of flood scale depends largely on where they live and what they have experienced. Throughout geological history extreme weather events have generated large-scale floods and these have transported very large volumes of sediment. The character and scale of flooding in Britain clearly changed through geological time but most of the sedimentary rocks from the Devonian to the Holocene contain flood-generated deposits. Currently many of these deposits may be un-recognised and their environmental significance un-interpreted. We know remarkable little about sediment transport and deposition in major floods and diagnostic features of the deposits are poorly documented.
This talk will present material from a series of related research programmes on sediment transport and deposits in extreme events. One research programme has been attempting to understand sediment transport and deposits in tropical-cyclone induced floods in North Queensland, Australia, in which millions of tonnes of sediment can be discharged into the Coral Sea in a matter of hours. Laboratory experiments are being used in attempts to study sedimentary structures under fast, sediment charged flow conditions and to study the fate of high sediment load discharge into the sea. A new research programme is studying flash floods and mudflows that are responsible for a lot of devastation on the flanks of active and recently active volcanoes. Some comparisons will be drawn with the geological record.
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Thursday, 7th November. Jonathon Lee, Royal Holloway, Univ. of London. 7:30 pm Friends Meeting House
Was Norfolk glaciated by Scandinavian ice during the Pleistocene?
The concept that some glacial sediments (the North Sea Drift/CromerTills) in Norfolk were deposited by Scandinavian ice is a fundamental principal of East Anglian geology that is based on little more than supposition. This presentation addresses the issue of whether Norfolk was glaciated by Scandinavian ice during the Pleistocene through the lithological analysis of the regions' till and sand and gravel deposits
Thursday, 23rd January. Paul Whittlesea, GSN 7:30 pm Friends Meeting House
The litho- and bio-stratigraphy of the Upper Beeston Chalk: a correlation between the north Norfolk coast and Caistor St. Edmund chalk pit, Norwich.
Knowledge of the detailed stratigraphy of the Upper Beeston Chalk, (Campanian, zone of Belemnitella minor sub. sp. II), is absolutely vital for providing a context within which to collect material for study and correlate exposures. A project to map the inter-tidal exposures between Sheringham and West Runton has produced a detailed, synthetic vertical section for the coast documenting the lithostratigraphy. Using this it has been possible to collect a substantial volume of palaeontological material with great accuracy and make comparisons with the only extant major inland section at Caistor St. Edmund chalk pit to the south of Norwich. As a result it is now possible to demonstrate a very close correlation between the two sections. The palaeontological data collected will be discussed as will the possibility of further sub-dividing the Beeston Chalk.
Thursday, 20th February, 2003 Vannessa Banks, GSN 7:30 pm Friends Meeting House
Human impacts on the hydrogeology or the River Lathkill, Derbyshire