Field Trip Guide Book: Regional Tectonic and Structural Geology of Barito Basin :
An Implication For Petroleum System
Instructor: Dr. Dardji N.
Years: 2015
An Implication For Petroleum System
Instructor: Dr. Dardji N.
Years: 2015
Tectonic event and sedimentary cycles of Barito Basin (Satyana, 1995)
|
REGIONAL GEOLOGYThe Barito Basin is located on the eastern margin of Cretaceous Sundaland (Hamilton, 1979). Recent configuration of Barito Basin is asymmetry, which tend to be deeper eastward and steeply closer to Meratus Ridge. Barito Basin is categorized as foreland basin (Kusuma and Darin, 1989). Kusuma and Darin (1989) stated that the basin was initiated by Paleogene graben system trending NW – SE, filled by Early Tertiary sediment of Tanjung Formation. The structures originated through a number of mechanisms: (1) compressional movement along the restraining bends of wrench faults, (2) en echelon structures adjacent to wrench faults, and (3) direct inversion of NE-SW aligned Paleogene normal faults. The structural-stratigraphic evolution of East Barito inversion structures has provided ideal conditions for the accumulation of hydrocarbons
|
STATIGRAPHY
Barito Basin contains a relatively thin layer of Paleogene sediments which were deposited in a generally marginal to shallow marine environment, and a much thicker Neogene section deposited in a foredeep basin paralleling the emerging Meratus Mountains. The oldest rocks above the unconformity are assigned to the Tanjung Formation. They were deposited from Middle Eocene to late Early Oligocene (Witts et al., 2011). Tanjung Formation consists of coal-bearing fluvio-tidal and marginal marine strata that record the initial stages of basin formation, followed by the development of a broad, flat coastal floodplain undergoing transgression. Tanjung Formation is overlain in the south by shallow marine carbonates of the Berai Formation, and in the far north by intertidal and fluvio-deltaic strata of the Montalat Formation. These formations were deposited from Late Oligocene to Early Miocene (Witts et al., 2011). Marginal marine to fluvio-deltaic sedimentary rocks of the Warukin Formation overlie these formations, and record a period of regression and basin inversion until the Plio-Pleistocene (e.g. Satyana et al., 1999). A westwards-thinning wedge of coarse clastics assigned to the Dahor Formation which interfingers the Warukin Formation in the east, and records the un-roofing of the Meratus Complex in the Plio-Pleistocene.
Based on tectonic event that occurred during tertiary, Satyana (1995) grouped Barito Basin Tertiary sediments into five depositional cycles : (1) middle Eocene - late Eocene, (2) early Oligocene, (3) late Oligocene - earliest Miocene, (4) early Miocene - middle Miocene, and ( 5 )late Miocene – Pliocene.
Based on tectonic event that occurred during tertiary, Satyana (1995) grouped Barito Basin Tertiary sediments into five depositional cycles : (1) middle Eocene - late Eocene, (2) early Oligocene, (3) late Oligocene - earliest Miocene, (4) early Miocene - middle Miocene, and ( 5 )late Miocene – Pliocene.
stop site and outcrop
|
|
Mesozoic granite; white to grey with fractures partly filled with dikes and Middle Tanjung Formation, Interbedded of Sandstone and Shale with Coal intercalation.
|
|
|
Interbedded conglomerate and sandstone, showing cross bedding sedimentary structure and channel feature of Lower Tanjung Formation and Thick Bedded to Massive red conglomerate and sandstone of Lower Tanjung Formation
|
|
|
Bedded Limestone of Berai Formation and Thick Bedded to Massive red conglomerate and sandstone of Lower Tanjung Formation.
|
|
|
Warukin Formation
|