IUGS SUBCOMMISSION ON CRETACEOUS STRATIGRAPHY (SCS)

Chair  
Professor Peter F Rawson, Department of Earth Sciences, University College London, 
Gower Street, London WC1E 6BT, United Kingdom
Phone   + 44 20 7679 7326	Fax   + 44 20 7388 7614	       E-mail   p.rawson@ucl.ac.uk	

Vice-Chair  
Dr Annie V. Dhondt, Institut Royal des Sciences Naturelles de Belgique, 
Rue Vautier 29, B-1000 Brussels, Belgium
Phone   + 32 2 627 44 92		Fax   + 32 2 627 41 74	       E-mail   Annie.Dhondt@naturalsciences.be 

Secretary
Dr Silvia Gardin, ESA-CNRS 7073, Laboratoire de Micropaléontologie, case 104, 
Université Pierre et Marie Curie, 4 Place Jussieu, F-75252 Paris 05, France
Phone   + 33 1 44 27 49 86	Fax   + 33 1 44 27 38 31	       E-mail   gardin@ccr.jussieu.fr
_________________________________________________________________________________________

NEWSLETTER NS.5
December 2002

CHAIRMAN’S INTRODUCTION

Newsletter NS.4 was issued in June this year, and included updating reports on our various Working Groups. Since then there have been several meetings relevant to our activities, and this Newsletter concentrates on reports on them. In particular, the Santonian Group had a very successful meeting in Spain in September, and we are very grateful to Marcos Lamolda, the chair of the group, for organising it. 

The response to our appeal for volunteers to join the Berriasian (and Jurassic-Cretaceous boundary) WG has been disappointing, so do please contact me as soon as possible if you are interested in joining it. And, as always, please pass this Newsletter on to your research colleagues. Don’t forget that any Cretaceous specialist who can contribute to our main aim, which is to propose GSSPs, is welcome to join the appropriate Working Group(s).

Pete Rawson

WALTER CHRISTENSEN (1942-2002)

It is with much sadness that we report the death of our former chairman, Walter Christensen.  Walter was a long-serving member of our Subcommission and chaired it from 1990 till 1994. He was an outstanding specialist on the Upper Cretaceous and especially on the belemnite faunas and will leave a big gap in his areas of expertise. But most of all we will miss his zest for life. He was always excellent company, and those of us who shared his love of jazz have lost a good musician as well as a special friend.

ICS MEETING, URBINO (14-16 JUNE 2002)

As reported in our last Newsletter, the International Commission on Stratigraphy (ICS) invited chairs of subcommissions and ICS officers to get together (for the first time ever!) for a meeting on Future Directions in Stratigraphy. This took place from 14-16 June in Urbino, Italy. What threatened on paper to be an unexciting ‘administrative’ meeting actually proved to be very stimulating and well worth attending! The meeting was concerned firstly with an overall timetable for completing the GSSP programme, which it was agreed must be achieved urgently, with the very last GSSPs approved not later than 2008. But its main concern was with what happens afterwards, and ideas suggested include creating an ‘International Association of Stratigraphic Geologists’, compiling comprehensive stratigraphic databases,  publishing a stratigraphic journal (possibly electronic) and preparing teaching resources. Some of these are already being followed up, others may materialise later. A full account of the meeting, with an ‘Executive Summary’, is on the ICS website: www.stratigraphy.org  - click onto ‘news’.
Pete Rawson

FIRST INTERNATIONAL WORKSHOP OF THE LOWER CRETACEOUS AMMONITE WORKING GROUP (LYON, 11 JULY 2002)

The Lower Cretaceous Ammonite Working Group of the SCS is the successor of the Lower Cretaceous Cephalopod Team that formed part of the IGCP Projects 262 and 362 respectively. The latter team had organized 5 Workshops and this was the first workshop under the ICS umbrella. It was organized by Stéphane Reboulet (Université de Lyon 1) directly after the 3rd French Symposium on Stratigraphy, STRAT 2000 (Lyon, 8-10 July 2002). The workshop was attended by 18 members from 13 countries. The attendants agreed to call the group the Kilian Group after the famous French palaeontologist Wilfrid Kilian (1862-1924).

The aims of the Kilian Group are: (1) to construct a standard ammonite zonation for the Lower Cretaceous Series, which is in fact the zonation for the Mediterranean Faunal Province, where all Lower Cretaceous stages, except the Albian Stage, were defined, (2) to develop ammonite zonations for other key areas in the Tethyan, Boreal and Austral Realms and to calibrate them with the ‘standard’, and (3) to make recommendations on the definitions of Lower Cretaceous stage and substage boundaries to the appropriate stage Working Groups of the Subcommission. 

The workshop concentrated on the current Lower Cretaceous standard (i.e. Mediterranean) 
ammonite zonation, summarized by Hoedemaeker & Rawson (2000 - Cretaceous Research 
21, 857-860). During the meeting several amendments were agreed to the current scheme, 
mainly in the Valanginian, uppermost Hauterivian and Lower Barremian. The Valanginian 
zonation has been modified several times over the last 10 years, and the Kilian Group 
accepted that it now needed stabilising. Agreement was reached after considerable debate! A 
summary of the results of meeting has been submitted to Cretaceous Research, while a 
detailed paper on the Valanginian zonation is being prepared by several group members for 
publication in the same journal.
Pete Rawson

MEETING OF THE GERMAN SUBKOMMISSION FÜR KREIDE-STRATIGRAPHIE  (MAASTRICHT (2-5 SEPTEMBER 2002)

The yearly excursion of the German Subkommission für Kreide-Stratigraphie was to the Upper Cretaceous in the extended type area of the Maastrichtian Stage. It was mainly organised by John Jagt in the area between Lixhe (Liège province) and Aachen, which of course includes the stratotypical Maastrichtian; stratigraphically the outcrops include Santonian to Danian strata.

Most of the 35 participants stayed in a hotel opposite the entrance of the famous ‘caves’ of the Geulhemmerberg. This simplified the logistics of the meeting. We met on the evening of Monday September 2 – and a lot of informal but, as we all know, important discussion took place over the first few beers.

On Tuesday September 3 we visited the CBR quarry at Lixhe and the CBR Romontbos quarry at Eben-Emael – Campanian, Lower and Upper Maastrichtian - on the Belgian side of the Meuse River. In the evening the business meeting of the group took place under the competent direction of chairman Jörg Mutterlose at the Natuurhistorisch Museum in Maastricht, and also included a visit to the Museum and to its impressive new mosasaur.
On Wednesday September 4 we visited the ENCI quarry near Maastricht, the Ankerpoort-Curfs quarry at Geulhem, and the Geulhemmerberg ‘underground’ K/T boundary section – that day we saw the complete Maastrichtian as accessible on Dutch territory.  The Geulhemmerberg section was shown and explained to us by Jan Smit and Hubert Vonhof from the Free University of Amsterdam. 

On Thursday September 5 we saw Santonian, Campanian and Lower Maastrichtian strata  - the highest levels of the day (Vijlen Fm.) at the old quarry near Altembroeck (Limburg, Belgium), the Aachen Sands at the Käskorb Quarry at Kelmis (Liège, Belgium) and again in an unusual facies at the Kalkwerk Hastenrath on the east end of the Stolberg, Aachen (Germany). Agnes Viehofen from the Geologische Dienst NRW in Krefeld showed us this last quarry.
Annie Dhondt 

SANTONIAN WG:  MEETING ON THE CONIACIAN -SANTONIAN BOUNDARY, BILBAO, SPAIN (13-17 SEPTEMBER 2002)

22 scientists from 10 countries (including Japan, Russia and the USA) met on September 13 at the Colegio Mayor Miguel de Unamuno of the Universidad del País Vasco, in Bilbao, Spain. This ‘university residence’ is a very comfortable student hostel, where all the participants except Marcos Lamolda (who preferred, understandably, to sleep at home) stayed throughout the meeting. The first evening during a most pleasant icebreaker party we exchanged news, looked at posters and enjoyed a wonderful assortment of tasty titbits and Spanish wines.

On Saturday, September 14, we travelled to Olazagutia. In the Cementos Portland quarry (Cantera de Margas) at Olazagutia (Navarra) two sides of the quarry were studied by the group, but more time was spent on the east side. M. Lamolda, J. Gallemi, G. Lopez, R. Martinez, J.M. Pons  and C.R.C. Paul explained the results of their work on the quarry, below and above the level of the Coniacian/Santonian boundary. Among the macrofossils found while our group was studying the eastern side mainly echinoids and magnificent inoceramids should be mentioned. The condition of the outcrop was not ideal but the indications of the excursion leaders were thorough and the various levels were clearly marked.

After the visit to the Cementos Portland quarry the participants were presented a memorable lunch at the inn which the late Gundolf Ernst  patronized during his pioneering geological work in the area.         . 

On Sunday, September 15, we visited the Villamartin (Burgos) section situated on the northern part of the North Castilian Platform (El Paño Range) showing an intermediate position between basin and platform sequences. In the Villamartin section the Coniacian-Santonian  boundary is situated in a part of the section with abundant macrofauna especially in the lower part of the section.  J.M. Pons, J. Gallemi, G. Lopez and R. Martinez were the leaders of this excursion.
 
On Monday, September 16 we had scientific sessions: Jake Hancock gave an introductory lecture on  ‘Some Coniacian-Santonian boundary sections in the USA’, explaining amongst other things why the Texan locality Ten Mile Creek near Dallas mentioned in Brussels (1995) as a possible candidate for the Coniacian-Santonian boundary is not completely satisfactory. We also had papers and posters on varied happenings (Foraminifera by Petrizzo, and by Premoli-Silva and Petrizzo; Nannofossils by Melinte and Lamolda; benthic Foraminifera by Peryt and Lamolda; bivalves by Dhondt; brachiopods by Gaspard) and on varied regions  (the South Central Pyrenees by Gallemi et al.; the Seaford-Head exposures in England by Hampton et al.; the Mangyshlak Peninsula and the Peri-Caspian Basin (W. Kazakhstan) by Kopaevich and Beniamovskii; on comparative microfossil chronostratigraphy of the W. Interior and U.K. Chalk by Sikora et al.;  Japan  by Toshimitsu et al.;  the Pueblo section (Colorado, USA) by Walaszczyk and Cobban) all around the Coniacian/ Santonian  boundary. Finally, to remind us that geological history extends beyond the Santonian, Chris Paul gave a talk on stable isotopes at Zumaya. 
The booklet containing the abstracts of the meeting and the excursion guides also contains abstracts on the Coniacian-Santonian transition in the Urals (Amon), in the Basco-Cantabrian Basin (Gräfe), in Germany (Tröger), in Austria (Wagreich) and in the Russian Far-East (Yazykova and Zonova).

The last item on the scientific agenda concerned the suitability of Olazagutia as a possible boundary stratotype. Long discussions stressing positive and negative aspects of the quarry followed. 

On the negative side the discussion mainly stressed the fact that the Olazagutia section is situated in a working quarry and that the ammonite fauna is poor. The first aspect means that its accessibility in the present circumstances is not fully guaranteed. The lack of ammonites means that correlation with other regions using macrofossils can best be based on inoceramids and echinoids. 

On the positive side it was mentioned several times that the micropalaeontological data on the section are well studied including nannofossils, foraminifers (both planktonic and benthic), and that stable isotope dates exist. Also the inoceramid Cladoceramus undulatoplicatus occurs fairly commonly thus making it possibly to locate the Coniacian/ Santonian boundary fairly precisely.     

It was proposed by several participants that other sections should be designated – or in case this is not possible according the ICS rules - to add a ‘para boundary stratotype’, for example at Villamartin. The alternative sections studied in the same area were shown to be either less useful because they are situated in sediments with poor microfauna or are less well studied.

The participants finally agreed that the Olazagutia section should be chosen among the three possible candidates for the Coniacian-Santonian boundary stratotype designated in Brussels (1995).

For the immediate future our Spanish colleagues agreed to prepare a very detailed description of the eastern side of the Olazagutia quarry as it is today and to publish this, possibly in Cretaceous Research. This description can also be used for submission first to the members of the WG and then to the voting members of the Cretaceous Subcommission, even if for this report to the Subcommission and to the ICS some aspects must be added (such as the comparison to other similar sections). 

It was stressed and agreed upon that beyond the agreement with the present quarry owners a complete protection of the geological site should be obtained if possible by the authorities of the region (Navarra). According to the Spanish participants, laws existing in Spain make this possible.

A short speech of thanks to the local organiser and to all the participants for having taken such an active interest concluded the scientific part of the meeting. 

The meeting was concluded by a very pleasant evening banquet. 

It is hoped that the papers presented at the meeting will be published in a special volume of Cretaceous Research and Annie Dhondt has sent details about preparation of manuscripts to all  participants who submitted abstracts.
Annie Dhondt

FIELD EXCURSION TO THE BASE MAASTRICHTIAN GSSP

The Maastrichtian GSSP was the first Cretaceous GSSP to be ratified, in 2001. It was defined in a quarry at Tercis les Bains, SW France. Gilles Odin, chairman of the Maastrichian WG, led a field excursion there on 6-7 September 2002 and we are grateful to Edwige Masure, president of the French Group of Cretaceous Studies, for the following report, which indicates how the site is controlled and the GSSP now marked:

The first day was dedicated to the general presentation of the local and regional geological context of the Aquitaine Basin. The second day was spent entirely in the Tercis quarry. Visits are now strictly controlled by the Tercis town council and scientific committee. The southern outcrops of the quarry are very interesting from an educational point of view. They show sedimentary successions from littoral to platform environments very rich in fossils (oysters and rudists of Turonian-Coniacian age) to a more open marine sedimentation characterised by lithographic limestones.

The northern part of the quarry is dominated by the spectacular, natural outcrop of the ‘Mur de Bédat’ (Bedat wall), a 20 metre thick hard siliceous limestone wall overhanging the Adour River.

The stratigraphically most significant outcrops are those at the eastern end of the quarry, where six platforms allow observation of the deposits some distance away. Platform P IV is the reference section for levels 100 to 162 and contains the GSSP. The latter is now marked by a metallic plate and spike at level 115,5.  It is the acceleration of biological events around level 115,5, guided by the FO of the ammonite Pachydiscus neubergicus, which marks the Campanian-Maastrichtian boundary. 

The Aquitaine Basin, situated between the boreal and tethyan domains, is characterised by a mixed flora and fauna, which makes the Tercis quarry a unique site for global correlation.
Edwige Masure

FUTURE MEETINGS

Aptian ammonite successions, boundaries and correlations, Cassis, France, 15-18 September 2003
The Kilian Group and an informal French ‘Gargasian Working Group’ are sponsoring a international workshop on the Aptian ammonite successions of SE France and wider problems of Aptian correlation. Further details may be obtained from Pierre Ropolo: Email ropolo.pierre@wanadoo.fr

32nd International Geological Congress, Florence, Italy, 20-28 August 2004
The Subcommission will be running a half day session on Cretaceous correlation and Stage boundaries as session G22.9 of the scientific programme. Further details will be announced soon.

NEW PUBLICATION

The former IGCP Project 362 (Tethyan and Boreal Cretaceous Correlation) has now published the proceedings of its final meeting. The papers are authored by 19 specialists, who have discussed possible seaways between Boreal and Tethyan basins, their climatic regimes, fauna and flora. The volume includes a large, fold-out correlation chart and accompanying paper proposing a Boreal-Tethyan Lower Cretaceous correlation based on sequence and biostratigraphy which should stimulate much debate on both the methodology and the results.
The volume can be obtained  from:
Mgr Eva Luptakova, Library of Institute of Geology, Slovak Academy of Science, 
Dubravska 9,   842 26 Bratislava, Slovakia.  
Price 22 Euros + 10 Euros for postage and packing.