AAPG International Distinguished Lecture with Prof. R.P. Koesoemadinata (UNPAD SC of AAPG)

In January 31th 2009, Padjadjaran University Student Chapter of AAPG conducted a course was given by Mr. Prof. R.P. Koesoemadinata with the tittle “Basin Concepts And Basin Classification In Indonesia”. The speaker presented the excellent and interested topic.

Taking a picture of participants and Mr. Prof. R.P. Koesoemadinata

At the beginning, Mr. Prof. R.P. Koesoemadinata explained us about type of the basin. Basin divided into four category. There is Physiographic Basin, Structural Basin, Sedimentary Basin, Petroleum Basin. Mr. Prof. R.P. Koesoemadinata also explained about the differences between each of the type of basin. In Indonesia there are sixty basins but not all of the basin content of petroleum because all basin only viewed from physiographic side. The lecture take a break for lunch and praying time.

Mr. Prof. R.P. Koesoemadinata explained about plate tectonic concept and Sedimentary basin

After break time, lecture was continued to the 2nd session. Mr.Prof. R . P. Koesoemadinata explained about The Concept of Tectonic Plate and Basin Evaluation.

Sedimentary basin have characteristic ,the most important feature of a sedimentary basin is the depositional interface which during certain time intervals is partly or entirely above or below sea-level and the sedimentary basin also can be partly or entirely involved in tectonic activity, such as folding, faulting and uplift to form a mountain range. A sedimentary basin does not necessarily have the shape of a geomorphologic basin, it could be a slope (clinoform) but is typically characterized by tectonic subsidence relative to its surrounding area. The basin margin is characterized by the wedge-out of sedimentary strata. In general a sedimentary basin is a tectonic feature.

Sedimentary basin where petroleum has been generated and accumulated in economic quantities not all sedimentary basin is capable of generating petroleum called Petroleum Basin. In general a petroleum basin is also a coal basin, but not all petroleum basins are coal basins and vice versa.

About hydrocarbon potential , only sedimentary basin with sufficient sedimen thickness, with an excess 2000 meter thickness. But, however thickness only doesn’t guarantee the generation of hydrocarbons.

All of participant stared at Mr. Koesoemadinata’s explanation

To understand what the sedimentary basin that explain above, we should know the Plate Tectonics. But, unfortunately almost people misunderstood about the difference of Plate and Crust. Plates is a rheological concept of a rigid outer sphere of the earth~ the lithosphere. And the other side, Crust is a mineralogical concept of the outer part of the earth and consists of: Continental Crust (granitic, formerly called sial) and Oceanic Crust (basaltic, formerly called sima).
Several basin classification based on Plate Tectonic have been proposed as:

• INTRA-CRATONIC/CONTINENTAL BASINS
  • Stable
  • Divergence (extensional)
  • Convergence (compressional)
  • Transvergence (trans-tensional)
• CONTINENTAL MARGIN BASINS
  • Active continental margins (convergence/transvergence)
  • Passive continental margins (divergence/stable)
• OCEANIC BASINS
  • Stable Oceanic Basins
  • Diverging Oceanic Basin
  • Converging Oceanic Basins
  • Transvergin Oceanic Basins

CONCLUSIONS

• Usage of the term basin is confusing (a mixture of physiographic, sedimentary and structural basins)
• To have a hydrocarbon potential outlining Indonesian basin map should be based on the occurrence of sediment thickness.
• Usage of the term basin, subbasins, troughs, lows is not consistent
• Indonesian basins are composite or poly-basins
• For composite basins the term basinal areas is suggested
• Whenever possible the term basin should be restricted to a single basin type according to plate-tectonic classification.

In the end of this lecture, the activity leader of Student Chapter AAPG Padjadjaran University gave an appreciation for Mr. Prof. R.P. Koesoemadinata support, energy, enthusiasm toward student development, by giving the memento. And then took a picture together in front of faculty.

Participants

Ninety two (92) students from Faculty of Geology, Padjadjaran University.

University of Padjadjaran Student Chapter (Indonesia)
American Association of Petroleum Geologist