Present: Bachtadse, Bachmann, Balini, Baud, Beutler, Courel, Dobruskina, Gaetani, Gazdzicki, Gomez, Hagdorn, Grauvogel-Stamm, Heckert, Jacobshagen, Kent, Kerp, Kozur, Lepper, Lozovsky, Mertmann, Mørk, Posenato, Rieber, Schulz, Shishkin, Soffel, Szurleis, Torok, Warrington, Yin.
The Chairman (Gaetani) opened the meeting at 16.10. and proposed adoption of the Agenda circulated by the Secretary; this was agreed by the meeting.
1. Apologies
The following notified the Secretary that
they would be unable to attend :
Carter, Cirilli, Dagys, Dickins, Eshet,
Glenister, Gradinaru, Grant-Mackie, Haas, Hancox, Hirsch, Kolar-Jurkovsek,
Kovács, Krystyn, Li Jinling, Marcoux, Michalik, Nakazawa, Newell,
Odin, Orchard, Ramovš, Rubidge, Seyed-Emami, Siblík, Silberling,
Steiner, Sudar, Sweet, Tatzreiter, Tiwari, Van Hinte, Visscher, Weitschat,
Wendt, Yang Zunyi, Zakharov.
2. Chairman's announcements
Albertiana 21 had been distributed in September; the Chairman welcomed the editor (Kerp) who had travelled from Münster specifically to attend the STS business meeting.
3. Working groups: progress towards GSSP selection
The Chairman noted that Triassic nomenclature used in literature appears to have stabilised since the STS meeting in Lausanne (October 1991) but no GSSPs have yet been selected for the Triassic. He stated that STS must deal with this situation, and introduced a review of the status, in relation to GSSP selection, of the stage boundaries which concern the STS.
3.1. Base of Triassic
Yin Hongfu (Chairman: Permo-Triassic Boundary Working Group, PTBWG) reported on his group's activity. A preliminary vote conducted in the PTBWG in 1995 had shown a large majority favoured Hindeodus parvus as the criterion for the base of the Triassic, and Meishan as the preferred candidate GSSP. A proposal on this basis will be submitted for a formal vote within the STS as soon as access to the site, and freedom to collect and remove samples, are guaranteed by the Chinese authorities; Yin hoped that this guarantee would be received soon.Yin summarised the biostratigraphic, magnetostratigraphic and other attributes of the Meishan section, and demonstrated the potential for correlation to other Chinese sections which have comparable lithostratigraphy and biostratigraphic control. He also summarised the attributes and ancillary correlation methods available from the Meishan section, and demonstrated the worldwide potential for correlation on the criterion selected.The Chairman acknowledged the efforts made by the Chinese investigators to develop a GSSP proposal for the base of the Trias.
3.2. Induan/Olenekian boundary
No information had been received from the Olenekian Working Group (Chairman: Zakharov). Baud commented that work by the Russians on a section in Siberia was impeded by financial constraints, and suggested that better progress might be made with a section near Vladivostok. Kozur doubted whether the Siberian sections would satisfy the ICS criterion of "accessibility"; Mørk said that, though they contain the best Olenekian ammonites, the Siberian sections are effectively inaccessible at present. Yin suggested that a section in Nevada or British Columbia should be considered.
3.3. Olenekian/Anisian boundary
The Chairman compared magnetostratigraphic records from Chios and Kcira; a small break occurs in the former and ammonoids are absent around the boundary at Kcira. The Dobrugea section has some magnetostratigraphy, and has conodonts and ammonoids, the latter studied but not yet described; he had urged progress on the description of the ammonoids in connection with the GSSP selection and had received a proposal for a workshop in Bucurest and Dobrugea in 2000, with an excursion to the Anisian boundary section and description of the ammonites in a volume to accompany this meeting. Kent questioned whether ammonoid FADs from Dobrugea were necessary if there is good magnetostratigraphy. The Chairman said that, if the ammonoid studies are completed, it will be necessary to decide whether ammonites or conodonts (Chiosella timorensis) are to be used as the boundary criterion; he also referred to the Nevada succession, but noted that this has few attributes; Kozur spoke in favour of the use of C. timorensis. The Chairman proposed a ballot to determine which criterion should be adopted; while this is in progress the magnetostratigraphy and conodonts would be published, progress on Dobrugea would be monitored and then a decision made on a ballot to select a candidate section; this proposal was accepted by the meeting.
3.4. Anisian/Ladinian boundary
The Chairman displayed an overhead of a questionnaire he had sent out about this boundary and, in response to comments from Kent, said that work is in progress to improve aspects of the magnetostratigraphic cover.
3.5. Ladinian/Carnian boundary
The Chairman referred to the poster exhibited during the Halle Symposium, to a field meeting held on the section at Stuores in July 1998, and to a summary proposal published in Albertiana21; a fuller proposal has been submitted to Rivista Italiana di Paleontologia e Stratigrafia.
3.6. Carnian/Norian and Norian/Rhaetian boundaries
No information had been received.
3.7. Non-Marine Triassic Working Group
Lucas (Chairman: Non-Marine Triassic Working Group, NMTWG) reported on the activities of the NMTWG, which had met during the Halle Symposium. Elsevier has agreed to publish an account of non-marine Triassic stratigraphy in 2000. Publication of a special issue of Palaeogeography, Palaeoclimatology, Palaeoecology, devoted to the Permian-Triassic boundary, and edited by Yin and Lucas, is imminent.
4. Secretary's announcements
The Secretary (Warrington) referred to a request posted to members, asking them to indicate their likely attendance at the Halle meeting, their current interest and activity in relation to Triassic stage boundaries, and to confirm their contact details. Nearly 60% of the membership had responded, and the cooperation of these people was appreciated. Those unable to attend the meeting had been invited to send comments on agenda items; these are attached to the full minutes and are summarised below:
Item 3.
Glenister (Chairman: Carboniferous-Permian Boundary Working Group, Subcommission on Permian Stratigraphy) expressed the view that "the Meishan proposal for the base of the Triassic system is one of the strongest ever presented for a stage or system boundary", and hoped that a vote on that boundary would be held soon. Grant-Mackie hoped that the P/T boundary selection would be finalised soon, as the Meishan section "seems to have virtually everyone's support".
Orchard: conodonts from the Otoceras woodwardi beds in Spiti are not Changxingian in age (Orchard & Krystyn in press Rivista Italiana di Paleontologia e Stratigrafia, manuscript forwarded to the PTBWG Chairman). Chiosella timorensis is a suitable conodont datum for the base of the Anisian; Neogondolella regalis is not suitable. Documentation of the conodont succession around the Anisian-Ladinian boundary in Nevada is being prepared; the FAD of Budurovignathus, at the base of the subasperum ammonite zone, is an easily recognized datum. Discussions during the visit to the candidate Carnian GSSP at Stuores showed that the taxonomy of Budurovignathus required further work.
Item 4.
Grant-Mackie: the T/J boundary in New Zealand appears, on palynological evidence, to be within the upper Otapirian, rather than at the Otapirian-Aratauran local stage boundary. Orchard: in N. America, conodonts disappear within Carter's terminal Triassic radiolarian zone; some taxa range higher than in Europe.
Warrington is also Secretary of the Triassic-Jurassic
Boundary Working Group (TJBWG) of the ICS International Subcommission on
Jurassic Stratigraphy. He attended the Jurassic Congress in Vancouver in
August, and participated in field excursions which included visits to proposed
base Jurassic candidate GSSPs in Nevada and British Columbia. These events
were very successful, and facilitated dialogue between workers from Europe
and the Americas. Four candidate GSSPs (in British Columbia, England, Nevada
and Peru) have been proposed; workers involved with each section have completed
a questionnaire based on the ICS Guidelines for GSSPs. The responses provide
a basis for objective comparison, and are an important step towards selection
of a candidate GSSP for the base of the Jurassic.
5. STS membership
The Chairman noted that the STS membership is large and includes many corresponding members. ICS statutes require part of the voting membership of a subcommision to be changed every four years. Consideration of the current membership list and the dates people had served as Voting Members showed that Anderson, Chen Chuzhen, Demathieu, Jacobshagen, Kapoor, Nakazawa, Ramovš, Siblik, Virgili, Wendt and Yang Zunyi should retire as Voting Members and become Corresponding Members.
The new, slightly smaller, voting membership would comprise the members of the STS Executive (Baud, Gaetani, Orchard, Rieber, Warrington, Zakharov), four new voting members (Hancox, Lozovsky, Menning, Yin Hongfu) and the following existing voting members: Bucher, Dagys, Gazdzicki, Grant-Mackie, Haas, Hirsch, Koike, Kovacs, Kozur, Krystyn, Lepper, Lucas, Marcoux, Nicora, Seyed-Emami, Sheng Jin-zhang, Silberling, Stanley, Tozer, Vijaya, Visscher, Weitschat. The proposed changes were agreed by the meeting.
6. Future meetings
Other meetings:
Albertiana: Chairman thanked the editor, Hans Kerp, for maintaining the high standard of the STS newsletter and recognized the considerable effort involved in publishing the two issues per year which were necessary for the newsletter to be effective. He also acknowledged the valuable contribution of Utrecht University, where the newsletter is produced and distributed.
The Chairman referred to Kerp's request for a change of editor and noted the response outlined in Albertiana 21. Kerp said his request reflected changes in his duties and a decline in his involvement with Triassic studies but, following offers from Orchard and Tozer to assist with editing text, he is prepared to remain as editor; the Utrecht support will continue if the editor remains in the region.
The "Annotated Literature" section, which occupies many pages in each issue of Albertiana,was discussed; this service is provided in other ways and several people felt that only the titles of relevant publications should be listed. Kerp said this would save much time, and the meeting agreed that this change should be implemented.
Mørk asked about putting the newsletter
on-line. Kerp was not enthusiastic but agreed to look into the possibilities
and report.
Kerp set 1 February and 1 August as deadlines
for receipt of contributions; he asked for cover illustrations, and that
titles for the publications list be sent to him by e-mail.
There was no other business.
The Chairman thanked Professor G. Bachmann, Halle, for the provision of facilities for the STS business meeting, and thanked delegates for their attendance and contributions. He declared the meeting closed at 18.00
G. Warrington
Secretary-General, Subcommission on Triassic
Stratigraphy
7 November 1998
(Abbreviated, by the Secretary,
from full minutes forwarded by him to the Chairman).
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