2004年工作进展：

（1）重要的研究内容：

  1. 系统研究峡东地区震旦系陡山沱组和灯影组的层型剖面和辅助剖面的岩石地层学、生物地层学、层序地层学和同位素化学地层学特征；

  2. 确定陡山沱阶和灯影峡阶的化石组合序列，阐明各主要生物群的面貌、时空分布和演化意义，选定划分生物地层的界线及其标志；

  3. 进行峡东地区范围内和以外其他地区陡山沱阶和灯影峡阶的对比；

  4. 利用现有资料进一步确定陡山沱阶和灯影峡阶的底界同位素年龄；

  5. 建立震旦系（陡山沱阶）底界的界线层型剖面和点。

（2）最新研究成果：

   So, an integrated approach is vitally significant in defining the initial boundary of the Terminal Proterozoic System. Isotopic indicators, e.g., Point 2 in the Jinguadun section, may be chosen as the stratotype point. A distinct signal of isotopic carbon variation may be accepted as an appropriate substitute for the first appearance of a particular fossil species. Reference points from other disciplines may help complete definition and promote global correlation. 

    陕南晚震旦世灯影期的高家山生物群是一个罕见的多门类化石组合，以后生动物管状化石为主并含多种遗迹化石、瓶状化石以及宏观藻类等，与世界其它地区同时期的以Ediacara型软躯体生物为特征的生物群面貌截然不同。自1975年首次发现以来，共描述发表了23个属57个种，通过重新研究和厘订，现将其归为9个属15个种。黄铁矿化和磷酸盐化是高家山生物群管状化石保存的显著特点，多种后生动物骨骼化石的出现表明生物矿化作用在晚震旦世已开始发生，“寒武纪大爆发”的序幕已经拉开。 
     以扬子区晚震旦世陡山沱期磷块岩化石库和早震旦世冰期沉积为主要研究对象，采用古生物学、古地理学、古生态学、沉积学、埋葬学、岩石地层学、生物地层学、同位素化学地层学、地质年代学等方法，广泛深入地研究了陡山沱期磷酸盐化化石库的生物群面貌和保存方式、震旦纪冰期事件的划分和对比、冰期事件造成的全球环境变化对生物演化进程的影响，并探讨了诸如瓮安生物群中的“动物胚胎”和“海绵化石”等一系列科学前沿中普遍关注的疑难问题。 
    首次利用从火山灰中分选出原生锆石晶体颗粒，测得贵州松桃寨郎沟锰矿剖面南华纪间冰期大塘坡组下部火山灰夹层的U-Pb年龄为663 ± 4 Ma。由于目前世界范围内都缺少新元古代斯图特冰期和马临诺冰期的锆石U-Pb年龄，这个测定结果显然非常重要，为确定南沱冰期和震旦系底界的年代提供了重要依据。
    根据现有数据推测，南沱组底界年龄很可能小于ca.650Ma, 陡山沱组底界（震旦系底界）年龄可能为ca.600Ma或更新一些。

TERMINAL PROTEROZOIC SYSTEM
15TH CIRCULAR - January 2003
I.U.G.S. SUBCOMMISSION ON THE TERMINAL PROTEROZOIC SYSTEM

1. Brief Chairman's Message..............................................1
2. Terminal Proterozoic System - Second Ballot...........................1-2
3. Description of Candidate Sections.....................................3-30
   1) Tianjiayuanzi, eastern Yangtze Gorges region, Hubei, China 
   2) Maldeota Section, Mussoorie Syncline, Krol Belt, Lesser Himalaya, India 
   3) Enorama Creek, Flinders Ranges, South Australia
   4) Wearing Dolomite Section, Flinders Ranges, South Australia
4. Field Trip Report: Neoproterozoic of the Avalon Peninsula, Newfoundland. 31-33

                  TERMINAL PROTEROZOIC SYSTEM - SECOND BALLOT
      I vote to place the initial GSSP of the Terminal Proterozoic Period at the designated point in the following section
Yes____ Tianjiayuanzi Section, eastern Yangtze Gorges region, Hubei,
        China
 No____ Maldeota Section, Mussoorie Syncline, Krol Belt, Lesser Himalaya, 
 No____ Enorama Creek Section, Flinders Ranges, South Australia  
 No____ Wearing Dolomite Section, Flinders Ranges, South Australia
 ____ I abstain.
 
Sun Weiguo
___________________________(Signature)

                         RESULTS OF THE SECOND BALLOT
     Completed ballots were returned by 19 of the 20 Voting Members (95%), a clear mandate under I.C.S. regulations.  The results of the vote are as follows, with the number of votes listed immediately before the name of the proposed section and point:
     I vote to place the initial GSSP of the Terminal Proterozoic Period at the designated point in the following section:
4    Tianjiayuanzi Section, eastern Yangtze Gorges region, Hubei, 
     China
1     Maldeota Section, Mussoorie Syncline, Krol Belt, Lesser Himalaya, India
12   Enorama Creek Section, Flinders Ranges, South Australia
1     Wearing Dolomite Section, Flinders Ranges, South Australia
1     I abstain
1     Did not vote
    The result is a 63% majority of votes cast (including the abstention).  Under I.C.S. regulations, any majority of 60% or higher consitutes a mandate.
Guy Narbonne, Secretary

IUGS Terminal Proterozoic Subcommission

TERMINAL PROTEROZOIC SYSTEM
18TH CIRCULAR - September 2003 
I.U.G.S. SUBCOMMISSION ON THE TERMINAL PROTEROZOIC SYSTEM


     TPS SUBCOMMISSION APPROVES A GSSP AND NAME FOR A NEW TERMINAL PROTEROZOIC SYSTEM

    Question 1: The initial GSSP of the new, terminal Proterozoic period shall be placed at the base of the Nuccaleena Formation cap carbonate, immediately above the Elatina diamictite in the Enorama Creek section, Flinders Ranges, South Australia.
    Approved by 16 of 18 voting-member ballots cast on this question (89%).
100% participation by the 20 voting members, with 2 declared abstentions.

    Question 2: The terminal Proterozoic Period shall be named the Ediacaran Period.
    Approved by 15 of 19 voting-member ballots cast on this question (79%).
100% participation by the 20 voting members, with 1 declared abstention.

                        RESULTS OF THE THIRD BALLOT
    Question 1: The initial GSSP of the new, terminal Proterozoic period shall be placed at the base of the Nuccaleena Formation cap carbonate, immediately above the Elatina diamictite in the Enorama Creek section, Flinders Ranges, South Australia.

_16_ I approve (80% of eligible voters / 89% of votes cast on the
     question)
     Janine Bertrand-Sarfati (France), Martin Brasier (UK), Nick Christie-Blick (USA), Ian Fairchild (UK), Gerhard Germs (South Africa), Brian Harland (UK), Hans Hofmann (Canada), Richard Jenkins (Australia), Andy Knoll (USA), Gopendra Kumar (India), Guy Narbonne (Canada), Wolfgang Preiss (Australia), Laurence Robb (South Africa), John Shergold (France), Anna Siedlecka (Norway), Malcolm Walter (Australia)
__2__ I disapprove
     Mikhail Fedonkin (Russia), Mikhail Semikhatov (Russia)
__2__ I abstain
     Sun Weiguo (China), Xing Yusheng (China)
__0__ Did not vote


                     RESULTS OF THE THIRD BALLOT
     Question 2: The terminal Proterozoic Period shall be named the:
__15__ Ediacaran Period (75% of eligible voters / 79% of votes cast
       on the question)
        Janine Bertrand-Sarfati (France), Martin Brasier (UK), Nick Christie-Blick (USA), Ian Fairchild (UK), Gerhard Germs (South Africa), Brian Harland (UK), Hans Hofmann (Canada), Richard Jenkins (Australia), Andy Knoll (USA), Gopendra Kumar (India), Guy Narbonne (Canada), Laurence Robb (South Africa), John Shergold (France), Anna Siedlecka (Norway), Malcolm Walter (Australia)
__0__ Ediacarian Period
__2__ Sinian Period
       Sun Weiguo (China), Xing Yusheng (China)
__2__ Vendian Period
       Mikhail Fedonkin (Russia), Mikhail Semikhatov (Russia)
__1__ I abstain
       Wolfgang Preiss (Australia)
__0__ Did not vote


                      Reasons for Disagreements 
1.The Enorama proposal does not fulfill the essential requirements
  of a GSSP.

To place the initial GSSP of the TPS at "the base of, or a horizon within the cap carbonate interval immediately above Varanger (or, Marinoan) glacial beds", suggested more than two possible positions for the initial GSSP. 

“The boundary stratotype must be selected in sections representing essentially continuous deposition”, “the worst possible choice for a boundary-stratotype of a chronostratigraphic unit is at an unconformity”, and the boundary-stratotype should be in marine sections “without major vertical lithofacies or biofacies changes”. (The International Stratigraphic Guide). 

2. The Ediacaran is not an appropriate name for the new TPS.

关于末元古系的正式命名

在目前流行的各种有关末元古系的名称中，震旦系（Sinian System ， Grabau 1922）拥有无可争辩的优先权。

Cloud and Glaessner (1982 ）的伊迪卡拉系（Ediacarian System) ，与Jenkins(1981 ）的伊迪卡拉系(Ediacaran System)时限不同，虽然与所推荐的地层范围一致，但“伊迪卡拉” (“Ediacara ”）这个地理名称已经被好几个不同等级的地层单位所采用，例如，“伊迪卡拉层” (“Ediacara Member” ， Jenkins et al. 1983）, “伊迪卡拉期” （ “Ediacarien stage”，Termier and Termier 1960）, “伊迪卡拉世” （“Ediacaran Epoch ”，Harland 1982 ）以及伊迪卡拉系。

为免除所有各种因不合适定义和命名可能造成的混乱和误解，采用一个新的名称不仅是可取的而且是必要的。同时，对于那些历史悠久并且在较大范围内广泛应用的名称，例如震旦系，则应在国家或区域年代地层表中合法地给予保留，它们的历史地位和用法应得到尊重和维护。特别是对一个新建立的末元古系而言，系级区域性地层单位总将是需要的，无论它们与标准全球年代地层表中对应的那个系的范围是否完全相符。

Comments by John Shergold: 
    Only two choices for establishing a GSSP for the base of the TPS: in China or in South Australia. 
    The advantages of China are: historical priority, long well exposed sections, unmetamorphosed, easy access, correlatability, documented biostratigraphically, chemostratigraphically, geochronologically. A disadvantage may be that there may be a disconformity between the Nantuo and Doushantuo Formations. 
    Nevertheless, Weiguo has submitted an elegant proposition, and I like the suggestion of the new name, Xilingian, because it is unambiguous. 
    On the face of it, proposals from Australia are also strongly presented. I would favour a GSSP within the Nuccaleena Formation, preferrably at the maximum flooding surface advocated by Malcolm and Wolfgang to avoid any potential disconformity at the base of the formation. The name Ediacaran (not Ediacarian) is globally potent, but there remains an element of possible confusion, so why not think of another one? 
    I imagine that South Australia will win the ballot for obvious geopolitical reasons (language, guaranteed access, availability of maps and air photos etc.).
    Thank you for your continuing work on the terminal Proterozoic. I certainly expect that the Yangtze sections will figure prominently as we enter a new phase in our discussions concerning the characterization and subdivision of the terminal Proterozoic system.  
Guy Narbonne, Secretary
IUGS Subcommission on the Terminal Proterozoic System