N126 Tectonics of SE Asia: Problems and Models

Course Facts

Course Code:
N126
Duration:
3 days
Type:
Classroom
CEU:
2.4 Continuing Education Units
PDH:
24 Professional Development Hours
Certificate:
Certificate Issued Upon Completion

Summary

This course provides a geological background to understanding the Late Mesozoic to Cenozoic history of SE Asia. This region includes Sundaland and its abundant hydrocarbon-rich basins and frontier regions of eastern Indonesia. The Mesozoic and Cenozoic geological development will be illustrated by computer animations. Subduction processes in the region are fundamental to its evolution and proposed basin-forming mechanisms include backarc extension, subduction rollback, strike-slip faulting, mantle plume activity.

Duration and Training Method

A three-day classroom course comprising of training through lectures and discussion. The Mesozoic and Cenozoic development of SE Asia will be explained using computer animations.

Participants will learn to:

  1. Identify the broad pre-Cenozoic configuration of SE Asian precursor tectonic blocks (terranes), their original affinities and ages of derivation/rifting from Gondwanaland and Cathaysia.
  2. Differentiate the primary sutures and bounding faults between terranes comprising southeast Asia. Demonstrate which blocks were constructed/added during the Cenozoic.
  3. Critically review the principal sources of age, palaeomagnetic and tomographic data from the region and compare their validity and the variety of possible interpretations.
  4. Understand the modern plate tectonic configuration and framework of SE Asia and the current tra-jectories and velocities of the main tectonic elements.
  5. Relate the major plate reorganisations at ~45 Ma, ~25 Ma and ~5 Ma to principal geological events including initiation of new subduction zones, region-wide stratigraphic events/markers and episodes of magmatism.
  6. Analyse the importance of long-term subduction processes at the south and east margins of Sundaland.
  7. Characterise the effects of subduction hinge movement and slab pull on magmatism and extensional processes. Recognise also that basin formation may not be easily related to gross tectonic events.
  8. Examine the role of tectonic events in SE Asia in generating topography to provideboth large-scale sediment supply and basinal sinks. Appreciate the exceptionally high sediment yields provided by the region.

SE Asia is an unusual area which deserves new models and thinking. The tectonics of the region provides a context for understanding the distribution of hydrocarbons. Conventional models for basin formation and orogenic development are often not appropriate, and may in fact mislead rather than inform our understanding. Many concepts and tools developed in other tectonic, geological and climatic settings need reconsideration and/or adaptation before they can be used in SE Asia.

The course will give an overview of techniques used in making plate tectonic and palaeogeographic reconstructions, and the data available to test them, such as isotopic dating, palaeomagnetism, GPS measurements and tomographic models. It will then focus on diff erent parts of SE Asia and surrounding regions which are important for understanding the tectonic history of the region and will discuss diff erent models for the development of these areas. The course will focus mainly on the Cenozoic history of the region but will discuss the Mesozoic, particularly the late Jurassic and Cretaceous, where appropriate.

The Late Mesozoic and Cenozoic geological development will be discussed in the context of a regional plate tectonic model for SE Asia and the SW Pacifi c. The model is illustrated by computer animations which cover the interval from 160 Ma to the present. These explain the Mesozoic breakup of Gondwana and the development of Australia–SE Asia collision which continues to the present day in East Indonesia. The long subduction history of the region is of fundamental importance to understanding its development.

The Cenozoic was a period of major geological changes which infl uenced life and climate in SE Asia. Indentation by India modifi ed the Eurasian continent but India-Asia collision was not the driving force in SE Asia. Other processes were clearly important, including Australia-SE Asia collision, and SE Asia illustrates the speed of change, the unexpected interplay of convergence and extension, and the importance of subduction as an engine of change. The late Cenozoic collision of SE Asia with the Australian continental margin has contributed additional complexity.  Of particular interest are the speed of processes, the importance of vertical movements, and the role of extension in a convergent setting, all of which are driven by subduction, but infl uenced by the age and character of the crust involved.

The course will review interpretations of the region and highlight changing ideas about regional tectonics as well as outlining new discoveries based on recent dating work, sediment provenance investigations and other field-based studies.

Who should attend

Geologists and geophysicists working in the region including new hires and staff new to southeast Asia. Senior staff , explorationists and managers who wish to understand the latest ideas and models for basin evolution in southeast Asia.

Prerequisites and linking courses

There are no prerequisites for the class but a basic understanding of geology is assumed.