Page 2 of 2

11.a. Palfy_TJB_comments

PostPosted: April 2nd, 2009, 10:20 am
by Junxuan Fan
Comment to the Triassic-Jurassic boundary GSSP and ASSP discussion

Dear Stan and all fellow Voting Members of ICS,

Beside the absorbing and all-important debate concerning the Neogene and Quaternary, the other issue presently on the table for discussion within the ICS is that of the Triassic-Jurassic boundary (TJB). While we have read through dozens of discussion items related to the N-Q debate, there have been an order of magnitude less feedback on the base Jurassic proposals.

As current chair of the Jurassic Subcommission (ISJS), I welcome the comments by Thomas Becker (recently re-posted a second time) and ICS vice-president Shanchi Peng. That the discussion started relatively late signals that the TJB issue has remained in the shadow of the N-Q debate in the past couple of weeks. Therefore I strongly suggest to postpone its deadline by a reasonable amount of time until after we finish the N-Q deliberation so the full attention of Voting Members can be devoted to it.

Every system/period has only one lower boundary, hence every subcommission’s most highly anticipated decision is on the GSSP of its own system’s lower boundary. The TJB case was referred to ICS after several difficult rounds of votes and substantial discussion within the Jurassic Subcommission and its TJB Working Group (TJBWG). The Jurassic community arrived at a decision and it is now the responsibility of the ICS to devote its undivided attention and use all of its expertise and experience when conducting a vote at this level of the TJB GSSP definition process.

The ISJS, on one hand, looks forward to a timely decision from the ICS, whereas on the other hand, is concerned that this decision be made after a discussion commensurate with the significance and complexitiy of the base Jurassic system boundary. Thus I return to the two comments received so far and hope that there will be more to follow in an extended time frame made available for discussion, after we will have the N-Q issue settled. Because some of Shanchi Peng’s comments concerned the structural setting, the exposure, and the access of the Kuhjoch GSSP candidate section, I believe that making available my photographic notebook (a virtual field trip, if you like) will help the discussion. The section, to my best knowledge, had been visited by few (if any) TJBWG or ISJS voting members other than the proposers prior to the vote concluded during summer 2008. The photos reflect the conditions encountered on an unguided field trip in early October 2008 and the labeling and interpretations are mine, although an earlier version of this PowerPoint presentation was shown to Axel von Hillebrandt, the main author of the GSSP proposal, and Nicol Morton, past chair of ISJS. I would appreciate if you could distribute the files among the ICS voting members, preferably also by posting it on the ICS website. Interested colleagues can also access it at these URL:
http://members.iif.hu/pal7413/Kuhjoch_T ... didate.pps
(PowerPoint file format, 6 Mb) or
http://members.iif.hu/pal7413/Kuhjoch_T ... didate.pdf
(PDF file format, 2,3 Mb)

I encourage all of you to carefully study the base Jurassic GSSP and ASSP proposals and to follow the ensuing discussion. What is at stake, after all, is fixing responsibly the second last of Phanerozoic system boundaries left undefined!

With best wishes,

Jozsef

Jozsef Palfy
Chair of ISJS (International Subcommission on Jurassic Stratigraphy

11.b. Kuhjoch_TJB_GSSP_candidate

PostPosted: April 2nd, 2009, 10:36 am
by Junxuan Fan
11.b. Kuhjoch_TJB_GSSP_candidate

12. Balini_Comments on the T_J boundary

PostPosted: April 2nd, 2009, 10:40 am
by Junxuan Fan
Comments of the Jurassic GSSP and ASSP proposals by M. Balini (STS chair)

The definition of a GSSP is often complex because the available sections are not perfect, but this is not the case with T/J boundary. Since many years the main problem with this boundary is the lack of fossils documentation in the boundary interval, that is related to the T/J crisis. For this reason some scientists tried to look for isotope events as potential marker events for the boundary.
One of the main difficulties that influenced the discussions within the TJBWG was the test of the correlatability of FOs in the lack/scarcity of elements to cross check the tests. By the end the TJBWG has selected the FO of Psiloceras spelae n. spp. at Kuhjoch section (note: in the proposal I have not found any synthetic statement with indication of primary marker event with bed number, accompanied by the additional marker events, with bed numbers).
I have a limited personal experience on the T/J boundary. In 2007 I visited the Ferguson Hill and I was really impressed by the good exposures of the succession and by the abundance and preservation of the ammonites. I know very well the amount and the high quality of the work done at Kuhjoch, because several data have been recently presented at Albuquerque “The Global Triassic” symposium (2007) and at Bad Goisern workshop on Upper Triassic chronostratigraphy (2008). My approach to the GSSP and ASSP proposals is focused on the selection procedure and clarity of the presentation of the data, and of course on my personal experience as stratigrapher. This examination leads me to emphasize four lacks in the GSSP proposal. The first is the voting procedure followed by the TJBWG, that is far from what is ruled in the ICS Statutes. The second is that part of the boundary succession has not been investigated. The third is the lack of good illustrations of the geologic and tectonic setting of the GSSP site. The last but not least is that, as far as I know, the taxonomy of the marker subspecies for the GSSP is not yet published or submitted for publication.
Are these lacks so important to justify a rejection of the proposal? I have not yet taken a decision, but for sure the fourth is important. I here briefly discuss the 4 points, together a short comment on the accessibility of the section.

Accessibility

I understand the doubts of Sanchi Peng on the accessibility of the Kuhjoch section, however with my experience of field works in the Alpine region I can confirm that the section cannot be considered of difficult accessibility. There is a path and the elevation of 500m above the car parking place both would simply mean about 1-1.5 hours of hiking, that is not really that much for motivated geologists interested to visit a GSSP of a System. Take also into account that the GSSP candidate is located in central Europe and not in a remote country.

GSSP voting procedure

I have been really surprised by the very short time given to TJBWG and SJS voting members to vote on the proposals. The voting procedure is defined in the ICS Statutes that clearly reports (point 9.7) that the time given to the voters is 60 days. As far as I know sometimes the WG leaders try to shorten the two months to one, but this is the first time that I read that a WG ballot is organized with deadlines fixed after 16 days (step 1: selection of primary marker), 12 days (step 2: selection of the preferred section) and 20 days (step 3). A more reasonable but still short time of 27 days was given to the SJS voting members. On the basis of my experience in the STS, when a WG leader wants to push for a vote with a deadline closer than 60 days (never less than 30 days, usually 45-50 days depending on the overlaps of deadlines and holidays) there is a consultation with the WG members that have to accept the short time for the ballot. I have not found any information on such a preliminary consultation in the reports of the TJBWG and SJS (Foreword.rev_1 and base_Jur._SCvoting_1). Of course this preliminary consultation is not a formal procedure suggested/required by the ICS Statutes, but it is reasonable and it also might help against any possible criticism for undemocratic procedure.
I can understand the wish by SJS to come to a conclusion by the Oslo 33° IGC, but in my opinion it is not possible to work independently from the rules defined by the ICS Statutes. If we believe that the rules and the Statutes are outdated we have to modify the Statutes. Twenty years ago the e-mail did not exist and the connections and votes of the members of the ICS were done by mail. At the present the e-mail allows extremely fast connections and exchange of documents, however, the last version of the ICS statutes is dated 2002 and still emphasizes (point 9.7) deadlines of 60 days.

Investigated interval at the GSSP section (see Fig. 1)

The succession investigated at Kuhjoch consists of the uppermost part of the Eiberg Member, 15 meters of the Tiebengraben Mb. and the Breitenberg Mb. About 7-7.5 meters of the Tiefengraben Mb seem to be covered and studied only at 3 spots (Hillebrandt et al. fig. 9, 10, 11, 12,15, 16, 17, 19 and 22). This interval, equivalent to 1/3 of the Tiefengraben Mb., is described as poorly exposed (Hillebrandt et al. p. 5) but Palfy’s reportage clearly shows that this interval has never been trenched.
In my life I have dug about 200 m of trenches in Southern Alps and abroad and I know how hard and dirty is this type of field work. For this reason I have the best consideration for the very hard work carried out by the authors at Kuhjoch, however I have to point out that in a such an important perspective as the presentation of a proposal for the GSSP of a system, the lack of investigations in 1/3 of the GSSP candidate section it is rather disturbing. No doubts that the boundary events are located in the studied part of the Tiefengraben Mb., but the 7-7.5 meters that were not trenched leave some question marks on the studied succession. This interval could have provided additional elements for the reconstruction of the phylogeny of Psiloceratids or it would have clarified the lack of tectonic overprint of the section.

Geologic and tectonic setting

The figures included in the GSSP proposal do not clarify this important point. The succession is overturned but there is no figure like a geological cross section illustrating the general setting of the area. Moreover the geologic map provided (Hillebrandt et al., fig. 5) is from an unpublished diploma thesis of a student from Berlin University, defended in 1974. Well, no geologic update since 1974? Frankly speaking, in a GSSP proposal I would expect to find something more advanced than a geological map of a student.

Publication of the paleontologic data

The agreement between A.v. Hillebrandt and J. Guex on the systematic of the species and subspecies of Psiloceras spelae is very important, because a shared taxonomy is crucial for the usage of fossils as stratigraphic markers. However P. spelae n. ssp. is the suggested marker for the Jurassic system, then the ratification of the GSSP by ICS would require some more solid and stable grounds than a simple agreement. The text explanation of the systematic of P. spelae is not really clear. For instance the number of specimens of P. spelae n. ssp. available from Kuhjoch is not reported, as well as the number of specimens from Nevada they have been compared with. In the text only 2 specimens from Nevada are clearly mentioned. The first actually “does not show the characters to be seen in P. spelae from the Alps”. Only the second seems to be comparable with the specimens from the Alps. I do not want to question the considerations of A.v. Hillebrandt and J. Guex who have an enormous experience on the systematic of early Jurassic Ammonitina, however they must write a short note on this issue before the ratification by ICS.



Fig. 1 – Poor exposure of the upper part of the GSSP section. (see the attachment)

13. Morton 03-30-09

PostPosted: April 2nd, 2009, 10:44 am
by Junxuan Fan
To: Palfy Jozsef <palfy@nhmus.hu>,
Finney Stan <scfinney@csulb.edu>
From: nicol morton <nicol.morton@orange.fr>
Subject: Jur.GSSP proposal
Date: Mon, 30 Mar 2009 19:58:36 +0200

Dear Stan and Jozsef,

Sorry for the delay in responding to Jozsef's remarks.

Jozsef is certainly correct that it would be unwise to PUBLISH the new subspecific name for the Austrian Psiloceras spelae before it is formally published in the article in press by Axel von Hillebrandt and colleagues. However, is the circulation of a proposal and ballot document within the ICS a publication? I would have thought not, but I might be wrong. Either way, inclusion of the new name is not important to the decision by ICS members.

The issue of separate votes on GSSP and ASSP is a difficult one. The votes were, as Jozsef states, separate in the Jurassic Subcommission but mainly for logistic rather than procedural reasons or principles. The two proposals were competitors until the very final stages so had to be processed separately - different teams of authors, different times of acceptable completion. Some members of the Jurassic Subcommission specifically stated that they would have preferred a single joint proposal and their views are clear from the comments.

I am very well aware that only two auxiliary stratotypes have ever been approved by (or proposed to ?) ICS and IUGS and BOTH are in the Jurassic - the Bajocian and the Bathonian. In each case there was a single proposal from one team of authors. For the Bajocian, the term ASP was used because that was the procedure at the time. For the Bathonian, members of the Jurassic Subcommission - prompted particularly by John Callomon as well as myself - accepted that the terminology proposed by ICS guidelines MUST be changed to reflect practical realities that a point is meaningless without its context in a section. Of course, the GSSP takes precedence; the purpose of an ASSP is to facilitate RECOGNITION rather than duplicate DEFINITION. In a real sense we were/are trying to educate the International Commission on Stratigraphy. [This may sound rather pompous - but some claim that the science of stratigraphy was largely first developed in the Jurassic.]

With all best wishes,

Nicol

14. von Hillebrandt & Leopold, in press

PostPosted: April 2nd, 2009, 10:51 am
by Junxuan Fan
14. von Hillebrandt & Leopold, in press

Finney's reply on Balini's comments (file 12)

PostPosted: April 6th, 2009, 8:04 am
by Junxuan Fan
====================================================
From: Stan Finney <scfinney@csulb.edu>
To: brian.pratt, brichard, charles.henderson, dharper, emolina, felix.gradstein, fhilgen, gehling.jim, isabella.premoli, jogg, Marco.Balini, martin.vankranendonk, mmelchin, p.bown, palfy, plg1, rbecker, scpeng, Junxuan Fan:, , nicol.morton <brian.pratt@usask.ca, brichard@NRCan.gc.ca, charles.henderson@ucalgary.ca, dharper@savik.geomus.ku.dk, emolina@unizar.es, felix.gradstein@geologi.uio.no, fhilgen@geo.uu.nl, gehling.jim@saugov.sa.gov.au, isabella.premoli@unimi.it, jogg@purdue.edu, Marco.Ba>
Subject: base Jurassic GSSP proposal
Date: 2009-4-4 5:23:52
====================================================

I write to further the discussion on the base Jurassic GSSP proposal. Comments have been few. Perhaps most of you were overwhelmed by the Q-N discussion, as well as you primary duties. I write in response to the concerns raised by Marco Balini, not to refute him, but to explain further from my perspective some of the points he raised. As ICS chair, I wish to remain unbiased, but still I study the GSSP proposals thoroughly and have my own opinion, and I wish to encourage others to do so as well. As mentioned in an earlier message today, I will be traveling 4-13 April. Soon after I return, I want to distribute the ballot, so please study the Jurassic GSSP proposal and the discussions.

Marco has several concerns with regard to the Kuhjoch section and the voting procedures (see attached file). My thoughts on these matters are as follows:

Voting Procedure:
I agree that the deadline for return of ballots was very short and much shorter than ICS Statutes dictate. On the other hand, the 60 days dictated also includes time for discussion, because, until I established a new policy, ballots were distributed with the GSSP proposal. Now, we distribute the proposal(s) and discuss it(them) for some time (30-60 days or more) before ballots are distributed. When time permits, I will ask the voting members to consider revising the 60 day statute in light of this. Still I believe that 30 days should be allowed once ballots are distributed. In spite of this, however, would it have made any difference in the voting. Of the 75 voting members on the TJBWG, 61 returned ballots, and the 48 voting yes would have allowed for a 64% approval, even if the 14 who did not vote voted NO. Thus, those supporting the Kuhjoch proposal submitted their votes in the short time and ensured its approval regardless of the missing votes. I note that of 22 voting members of the Jurassic subcommission, 21 returned their ballots, even with the short voting time, and if the missing ballot was a NO vote, the Kuhjoch proposal still would have been approved with a 64% majority vote. Would more time have resulted in a different result? I think not.

Investigated Interval:
A 7.5 meter interval in the upper part of the Tiefengraben Member in the Kuhjoch section was not excavated. If it was, more ammonite occurrences may be documented in the section better effecting correlation of the boundary interval. However, I note that below the covered interval, Psiloceras spelae is followed by P. ex gr. tillmanni and P. cf. pacificum, ammonite that in the Ferguson Hill section occur in the same succession and indicate that the exposed part of the Kuhjoch section does extend up into the Hettangian. Given the scientific significance and public interest in the Kuhjoch section were it approved as the stratotype, then efforts should be made to completely expose the Tiefengraben Member.

Geologic and Tectonic Setting:
I have no problem with their presentation in the proposal. Although overturned, the geology is relatively simple with contacts traceable along strike for long distances. And I see no need for a structural cross section because the structure is easy to visualize.

Publication of paleontologic data:
A systematic description of the key ammonites is in press in N. Jb. Geol. Palaont. with a 2009 publication date.
--
*************************************************************
Stanley C. Finney, Chair
Department of Geological Sciences
California State University - Long Beach
Long Beach, CA 90840 USA
Phone: (562) 985-8637
FAX: (562) 985-8638
e-mail: scfinney@csulb.edu
Co-Director, Environmental Science & Policy Program
Chair, International Commission on Stratigraphy (IUGS)

ballot for base Jurassic GSSP proposal

PostPosted: April 19th, 2009, 2:10 am
by Junxuan Fan
[Please download the attached word file]

VOTE

ON A GLOBAL STRATOTYPE SECTION AND POINT (GSSP) DEFINING

THE BASE OF THE HETTANGIAN STAGE, LOWER JURASSIC SERIES, AND JURASSIC SYSTEM

The Global Stratotype Section and Point (GSSP) defining the base of the Hettangian Stage, Lower Jurassic Series, and Jurassic System is proposed in the Kuhjoch section, Karwendel Mountains, Northern Calcareous Alps, Austria (47°29’02”N/11°31’50”E). The proposed GSSP is situated 5,80 m above the base of the Tiefengraben Member of the Kendelbach Formation and corresponds to the FO of the ammonite Psiloceras spelae GUEX subsp. tirolicum Hillebrandt & Krystyn. Other markers include the FO at the same level of the widely distributed continental palynomorph Cerebropollenites thiergartii, the FO 60 cm lower of the aragonitic foraminifer Praegubkinella turgescens and of the ostracod Cytherelloidea buisensis and the disappearance of the ostracod Eucytherura sagitta immediately above the point. The 13Corg record shows an initial negative excursion near the boundary between the Koessen and Kendlbach formations and a shift to more positive 13Corg at the proposed stratotype point.


The details of the GSSP are explained in documents previously circulated to all voting members and posted on the ICS website (http://www.stratigraphy.com).

Please indicate your decision below, and return your vote (preferably as an electronic e-mail) prior to 16 May, 2009 to:
Paul Bown, ICS Secretary
p.bown@ucl.ac.uk
with a copy to
Stan Finney, ICS Chair
scfinney@csulb.edu

I accept this proposal to define the base of the Hettangian Stage, of the Lower Jurassic Series, and of the Jurassic System, as described in the submission by the Jurassic Subcommission.

YES _____

NO _____

ABSTAIN _____

NAME:____________________ DATE:____________________

ICS Subcommission/Office:

COMMENTS: