Sunday, May 31, 2015

AAPG GTW- Tectonic Evolution and Sedimentation of South China Sea region: Note for File



TECTONIC EVOLUTION AND SEDIMENTATION OF THE SOUTH CHINA SEA
Note for file: summary of the AAPG GTW in Kotabalu, 26-27 May 2015
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AAPG organized a workshop on the Tectonic Evolution and Sedimentation of the South China Sea Region on 26 and 27 May, 2015, in Kota Kinabalu, Sabah, Malaysia. This workshop was supported by CCOP, and sponsored by IHS, Shell and Petronas. The Universiti Malaysia in Sabah (UMS) provided a local support for this event.







The organizer of this workshop were:
Herman Darman (Convenor) Shell E&P Malaysia
Ioannis Abatzis (Convenor) GEUS Denmark
Allagu Balaguru   (Technical Chair)  Sarawak Shell Berhad Malaysia

Advisory Board members:
M. Redhani B A Rahman   PETRONAS    Malaysia
Pham Thanh Liem    Vietnam Oil and Gas Group  Vietnam
Felix Tongkul     University Malaysia Sabah  Malaysia
Mark J. Harvey     Sarawak Shell Berhad   Malaysia

Technical Committee members:
Muluk A. Wahab    PETRONAS    Malaysia
Mario Aurelio     University of the Philippines  Philippines
Kevin Meyer     Talisman Energy   Vietnam
V R Vijayan     Minerals and Geoscience Malaysia  Malaysia
Tony Swiecicki             Cerberus Consultants   Malaysia
Tan Chun Hock     Talisman Energy   U.K.
Shahrul Amar Abdullah    PETRONAS    Malaysia
Giuseppe Cadel     ENI S.p.A    Italy
Phlemon George    Total E&P Malaysia   Malaysia
Roberto Barragan    Hess Corporation   Malaysia

Key note speakers in the workshop are:



  • Robert Hall (SEARG - Royal Holloway-UK), Title of presentation: Trenches, Troughs and Unconformities; Collision, Contraction and Extension: South China Sea, Borneo–Palawan and Sulu Sea. 
  • Claude Rangin (emeritus researcher in Nice Sophia Antipolis university-France), Title of presentation: Coeval Late Eocene- Early Miocene Extension in the East Andaman Basin and the South China Sea: Geodynamic Consequences and Implications for Hydrocarbon Research. 
  • Manuel Pubellie (Ecole Normale Sup√©rieure ENS-France) Collapse and Rifting in the South China Sea 
  • Christopher Morley (Chiang Mai University - Thailand), Title of presentation: Timing, Distribution And Tectonics Of Unconformities In The South China Sea 
  • Robert J Morley (Palynova - UK) Correlation across the South China Sea using VIM (Vietnam-Indonesia-Malaysia) transgressive-regressive cycles.


  • Summary of the workshop discussions are listed below. Please note that all these may change through time after further analysis and/or with more data availability.

    Common agreement
    1. Top Crocker Unconformity established
    2. Proto SCS is probably exist but not observable on the surface / outcrop. Dimension and location are debatable.
    3. The importance of understanding unconformities
    4. Many unconformities
    5. Slab pull is the favorite model compare to extrusion model but no accurate model. A hybrid model may be accepted by most.
    6. Need to sort out stratigraphy

    Common disagreement
    1. Unconformity distribution in term of time and space
    2. MMU is diachronous
    3. Interpretation on data
    4. Name of unconformities
    5. Definition for synrift; by geometry, lithology,age?
    6. Age of sea floor spreading and time for stop spreading
    7. Tectonic model
    8. Using Atlantic spreading model as analog

    Proposal / suggestion
    1. Correlation of unconformity if physical connection established (under CCOP, cros border stratigraphic correlation using seismic and well data
    2. Share dataset between companies and academics to bridge gaps in knowledge between blocks
    3. Increase data quality and consistency
    4. More collaboration between government, industry, academia
    5. More H2O (Hill to Offshore) / onshore-offshore integration
    6. Expand biostratigraphy education
    7. Workshop: biostratigraphy, focus on unconformity
    8. Publish type section
    9. Propose wells
    10. Regional SW-NE sections
    11. Cross Borneo gravity and seismic
    12. Form a committee on stratigraphy of SCS

    Not clear
    1. What is the cause of the end of the spreading?
    2. What CCOP can do to encourage governments to be more open on sharing data?
    3. Why CNOOC, SINOPEC, CNPC are not actively participate with other NOC like Petronas and Petrovietnam?

    Critical data to be released:
    1. Offshore Sabah seismic from coast to trough. To understand sediment transport and basin fill history.
    2. Sulu Sea seismic to understand basin fill history
    3. Comprehensive geophysical data pack around West Baram Line to understand crustal orientation and to understand sediment deposits on both sides of the line.
    4. Each country to release a data set which are open to anyone who like to analyze them. Well with biostrat, 2D Seismic
    5. Seismic data across political border. This well help to map the unconformity.
    6. Gravity and magnetic data need to be released.
    7, more seismic / data from Java and Sumatra as the make
    8. Chinese publications need to be circulated out
    9. Chinese wells and/or publications with Chinese well data

    Critical data needed:
    1. Deep seismic (e.g. For Sulu Sea, across Borneo) to confirm / investigate deep structures
    2. Seismic tomography
    3, Regional seismic across SCS to understand the distribution of the unconformities
    4. More outcrop studies to include gravity and paleomagnetic
    5. Stratigraphic tests in SCS margins

    Introduction

    The Geology of South China Sea website is prepared as a follow-up of the AAPG GTW in Kota Kinabalu, 26-27 May 2015. There is a need to share more knowledge, information and data in the region to understand the geology of this region. Hopefully this site can serve as a platform to accommodate the communication of the geoscientists who are interested on this region.