Tectonic Collision as important factor controlling hydrocarbon generation in Eastern Indonesia Basins : Case study in Timor-Tanimbar Trough

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  T1S5_O5 Tectonic Collision as important factor controlling hydrocarbon generation in Eastern Indonesia Basins : Case study in Timor-Tanimbar Trough Toha, B., Surjono, S.S., and Winardi, S.

  Department of Geological Engineering , Gadjah Mada University Yogyakarta 55281, Indonesia budtoha@yahoo.com ; budtoha@gmail.com

The present Eastern Indonesia is largely a result of the Neogene subduction of the NW continental margin of

Australian plate and its associated shelf, beneath the oceanic Banda Sea plate. The Tanimbar Islands are interpreted as the most distal parts of the Australian passive margin deformed and uplifted a foldbelt during the arc-continent collision. This collision complex is bounded to the south and east by Timor and Tanimbar Trough, interpreted as bathymetric depression (foredeep) within the Australian margin. The tectonic processes are further influenced by Late Miocene to Recent, strike-slip tectonics generated by the westward moving Pacific Plate. Since Neogene time, the Timor-Tanimbar Trough toward northwest Australian continental is actually foreland basin which developed from passive margin due to tectonic collision. The basin evolution passed through two phases of Palaeozoic extension, followed by Late Triassic compression, and then further

extension in the Mesozoic that culminated in the break up of Gondwana in the Middle Jurassic. Convergence

of the Australia-India and Eurasia plates in the Miocene to Pliocene resulted in flexural downwarp of the Timor-Tanimbar Trough and widespread fault reactivation in North-Western Australian Margin. This basin located in and near proven oil and gas fields such as Abadi, Bayu-Undan blocks in western area, onshore

Bird Head proven area in the north and Warim block in east. To the south, basin covered Goulburn sub-basin

with some hydrocarbon indication. The bending foreland basin which enhanced the "burner of the kitchen" due to collision is believed plays an important role for hydrocarbon generation in this case study area..

Nowadays hydrocarbon discoveries within Timor-Tanimbar Trough and its adjacent areas most rely on Mid

Jurassic Plover reservoir , as well as Jurassic sequence considered plays important role as petroleum source

rocks. The proven source rocks is mostly type III as indicated from Paleozoic-Mesozoic (Wessel, Goulburn,

Arafura, Kulshill Group and Plover Fm. of Troughton Group) which charged the North West Shelf of

Australian hydrocarbon field such as Petrel Sub-basin of Bonaparte Basin, Flamingo High and Sahul Platfom.

The Goulburn Group source rock is the most effective in the region. The Mesozoic sediments have demonstrated source potential for Money Shoal Basin, while Troughton Group equivalent is an important source rock in The Malita/Calder Graben as good as The Flamingo Formation. Other potential source rocks

  30th IAS MEETING OF SEDIMENTOLOGY 2nd - 5th September 2013

  Depart. of Geology Engineering Faculty of Engineering Universitas Gadjah Mada Tectonic Collision as important factor controlling hydrocarbon generation in Eastern Indonesia Basins : Case study in Timor-Tanimbar Trough Toha,. B.

  1 , Surjono,S.S.

  2 , and Winardi,S.

  3 1, 2, 3.

  Department of Geological Engineering , Gadjah Mada University Yogyakarta 55281 , INDONESIA

  30 th

  IAS MANCHESTER

  International Association of Sedimentologists

  Content :

  1. Introduction

  2. Tectonic setting and structural elememnts

  3. Tectonostratigraphy

  4. Case study : Timor- Tanimbar Trough ( basin modeling for tectonic collision and hydrocarbon generation)

  5. Conclusion

  World's Source Rocks & Reservoirs (after Kendall et.al.,2009 ; modified from Ulmashek and Klemme, 1990)

  World wide stratigraphic distribution of major source rocks Stratigraphic distribution of the major reservoir rocks world wide

  Indonesia Opportunities (Proven & Potential) for pre

  

‐Tertiary Petroleum Discoveries

  Eastern Indonesia Petroleum System

  

1. Petroleum systems are pre-Tertiary in majority, related

to the North Australian passive margin, affected by

microplate collision and large-scale strike-slip faulting

2. Source-rock age mainly from Mesozoic and possible

  

Paleozoic. Depositional setting include deltaic coal

and lacustrine shales ; shallow-deep marine clastic

and carbonates

  

3. Hydrocarbon types : diverse, includig wavy lacustrine

sourced crudes, light deltaic oils, medium marine oils, asphalt deposits, thermogenic and biogenic gas

  (Satyana, 2010 - Int.Symp. Meso-Palzoic Petr.Basin, IND)

  It has been suggested (Baillie et al 2004) that: “Throughout the eastern Indonesia region and the Timor Sea, reservoir quality sandstones were deposited in nearshore marine settings during the early Late Jurassic (see also Barber et al., 2003), prior to the so- called “Break-up Event”. (Early Tertiary)

  

It is proposed here that the Plover Sandstone reservoir of the Timor

Sea is synchronous with both the reservoir of the Abadi discovery

(Indonesia Masela PSC; Nagura et al., 2003) and the Tangguh Field,

suggesting a similar depositional setting over an enormous area of

coastline and nearshore marine environment. “

  Tectonics Provinces and Structural Trends , Eastern Indonesia

  

Characteristic of Petroleum System

_{AREA FIELD AGE FORMATION LITHOLOGY AGE FORMATION LITHOLOGY AGE FORMATION LITHOLOGY RESERVOIR SOURCE ROCK SEAL}

in Eastern Indonesia Fields

_TRAP

_{BINTUNI Ofaweri Group Jurassic Yefbie shale & coal Kembelangan shale Pop-up structure}

Wiriagar Permian Ainim Carbonaceous _{Klamono Miocene Kais Limestone Roabiba Vorwata Mid.Jurassic Kembelangan Sandstone shale & coal Late Jurassic Upper Claystone and pinchout Miocene Kais Intraformational} ^anticline _anticline

_{SALAWATI Walio Miocene Klasefet Limestone Klasaman Shale Miocene Klasefet Shale Thrust anticline}

_{BANGGAI Tiaka Jurassic Bobong Sandstone Jurassic Buya Marine shale}

_{SERAM Oseil Manusela Limestone Triassic Jurassic Late Jurassic Kola Shale Thrust anticline}

_{Kasim Early-Mid. Kanikeh Calc.shale Jurassic Manusela Carbonate} Early Pliocene _{TIMOR Bayu-Undan Mid.Jurassic Elang Sandstone Mid.Jurassic Elang Sandstone Abadi Mid. Jurassic Plover Sandstone Early. Jurassic Plover eq. Marine shale Early Cretaceous Echuca Shoals shale Normal Fault} Early Miocene Tomori Limestone Early. Miocene Salodik Shale & carbonate Late Miocene Matindok Marine shale Thrust anticline _{Late Miocene Mtindok Sandstone Plover Sandstone Plover Sandstone Early Cretaceous Echuca Shoals shale}

  (Surjono& Wijayanti, 2012)

  Stratigraphic Compilation of Eastern Indonesia (Pigram & Panggabean 1984, Hall 1995, Metcalfe 2006).

  Stratigraphic Compilation of Outer Banda Arc, Eastern Indonesia

  (Pigram & Panggabean 1984, Hall 1995, Metcalfe 2006).

  Proven Mesozoic-Paleozoic Sequences At Abadi Gas Field (Collided Australian Passive Margin Setting)

• Abadi Gas Field

  (Collided Australian Passive Margin Setting) + • A-B seismic section ( + estimated Abadi-1 well loc.

  Collision history of the Buton-Tukang Besi micro-continent

  Buton Basin Stratigraphy

  Note : Not much relationship discussion between Collision event with SR maturation

  Wangarlu Formation (Bathrust Island Group)

  Fluvio-deltaic to shallow marine sandstone of Middle Jurassic Plover Fm.

  Echuca Shoals Formation (Upper Flaminggo Group).

  Faulted Blocks.

  Echuaca Shoals

  Northern Bonaparte Basin  Eq. Elang Fm. in Elang & Kakaktua Field in East Timor-Australia JDA.

  Early Cretaceous Echuca Shoals Fm. (May exist along the flanks of Tanimbar Trough).

  Echuca Shoals Fm., Darwin Radiolarite?

  Faulted Blocks, stratigraphic.

  Greater Sunrise , Evans Shoal and Abadi  Sahul Platform, peri-rift basement high

  Paleozoic

  Tanimbar 

  Analogues with Bonaparte and Goulburn Graben

  Jigaimara Fm of Wessel Group, Arafura Geoup, Weaber Group, Kulshill Group

  Equivalent of : Goulburn Group, Arafura Group, Weaber Group, Kulshil Group, Plover Fm (Troughton group) intraformational mudstones, Kulshil Group, Flaminggo Group, Bathrust Island Group

  Faulted anticlines, horsts/tilted fault blocks, sub- thrust anticline, and stratigraphic traps

  

Regional Elements Petroleum System

of Outer Banda Arc – NW Australian Shelf

  Early

  Petroleum System Location Source Rock Reservoir Seal Trap Plover

  Petroleum System Location Source Rock Reservoir Seal Trap Plover

  Faulted Blocks.

  Greater Sunrise , Evans Shoal and Abadi  Sahul Platform, peri-rift basement high

  Early

  Fluvio-deltaic to shallow marine sandstone of Middle Jurassic Plover Fm.

  Echuca Shoals Formation (Upper Flaminggo Group).

• – Middle Jurassic Plover Fm. Mixed Type 2 and 3 (Gas)
• – Middle Jurassic Plover Fm. Mixed Type 2 and 3 (Gas)

  Faulted Blocks, stratigraphic.

  Wangarlu Formation (Bathrust Island Group)

  Faulted anticlines, horsts/tilted fault blocks, sub- thrust anticline, and stratigraphic traps

  Early Cretaceous Echuca Shoals Fm. (May exist along the flanks of Tanimbar Trough).

  Northern Bonaparte Basin  Eq. Elang Fm. in Elang & Kakaktua Field in East Timor-Australia JDA.

  Echuaca Shoals

  Paleozoic

  Tanimbar 

  Analogues with Bonaparte and Goulburn Graben

  Jigaimara Fm of Wessel Group, Arafura Geoup, Weaber Group, Kulshill Group

  Equivalent of : Goulburn Group, Arafura Group, Weaber Group, Kulshil Group, Plover Fm (Troughton group) intraformational mudstones, Kulshil Group, Flaminggo Group, Bathrust Island Group

  Echuca Shoals Fm., Darwin Radiolarite?

  PETROLEUM SYSTEM EVENTS CHART OF REGIONAL OUTER BANDA ARC- NW AUSTRALIAN SHELF

  Content :

  1. Introduction

  2. Tectonic setting and structural elememnts

  3. Tectonostratigraphy

  4. Case study : Timor- Tanimbar Trough ( basin modeling for tectonic collision and hydrocarbon generation)

  5. Conclusion

  During Paleozoic-Mesozoic times, eastern Indonesia region is considered to be part of

the northern margin of the Australian continent in which now become an active collision

margin. Stratigraphic section, at least from Cambrian to Cretaceous, shows the similarities which documented two tensional tectonics episodes; an Early Paleozoic infra-rift and a Late Paleozoic to Paleogene rift. The Pre-Tertiary sediments of eastern Indonesia are largely determined by the tectonic events. Rocks succession in this region mostly developed unconformbly overlying the highly metamorphic rocks of Devonian to Permian in which considered as basements. In Outer Banda Arc to Sula-

Buton region, Pre-Tertiary Sedimentary rocks were characterized by series of carbonate

rocks, which developed up to Tertiary times. Whereas in the Papua (Irian Jaya) region were marked dominant of siliciclastics rocks during Paleozoic to Mesozoic Times and carbonate rocks and shale in Tertiary times. Pre-Tertiary sedimentary rocks in some basins of eastern Indonesia were proven as producer hydrocarbon. Although Pre-Tertiary source rocks are widespread in Eastern Indonesia but the significant one were deposited primarily restricted to three time periods: Permian, Late Triassic and Early-Middle Jurassic. The Reservoir rocks are mainly belong to Mesozoic and Tertiary ages, where sandstone and carbonate rocks developed in Mesozoic and in Tertiary dominated by Miocene limestone and sandstones and also Pliocene sandstones. Traps are mainly contolled by thrust fault, normal fault and carbonate buildup, while. the syn-orogeny and passive margin shales provide as seal rocks.

STRUCTURAL ELEMENTS OF EASTERN INDONESIA

  Pertamina and Corelab ,1999

REGIONAL CROSS-SECTIONS

  Pertamina and Corelab ,1999

  Reconstruction of the Australian Continental Margin in the “Tectonostratigraphy”

BASIN EVOLUTION

  The basin developed during Banda Accretionary Prism Sahul Platform two phases of Palaeozoic extension, followed by Late Triassic compression, and then further extension in the Mesozoic that culminated in the break up of Gondwana in the Middle Jurassic (O’Brien et al, 1993).

  Convergence of the Australia-India and Eurasia plates in the Miocene to Pliocene resulted in flexural down warp of the Timor Trough and widespread fault reactivation in North-

  Reconstruction of the Western Australian Margin

  Australian Continental Margin in the Late Neogene before deformation took place  structurally very complex (Barber, et al., 2003).

  Discoveries within Timor-Tanimbar Trough  rely on Mid Jurassic Plover reservoir

NOWADAYS EXPLORATIONALIST MIND-SET PETROLEUM SYSTEM CHARACTERISTIC OF SOME FIELD IN EASTERN INDONESIA FIELD RESERVOIR SOURCE ROCK SEAL AREA

  Wiriagar Permian Ainim Carbonaceous anticline Vorwata Mid.Jurassic Kembelangan Sandstone shale & coal Late Jurassic Upper Claystone and pinchout

  

BINTUNI Ofaweri Group Jurassic Yefbie shale & coal Kembelangan shale Pop-up structure

Roabiba anticline

Klamono Miocene Kais Limestone Miocene Kais Intraformational

  

SALAWATI Walio Miocene Klasefet Limestone Early Pliocene Klasaman Shale Miocene Klasefet Shale Thrust anticline

Kasim Early-Mid. Kanikeh Calc.shale

SERAM Oseil Manusela Limestone Triassic Jurassic Late Jurassic Kola Shale Thrust anticline

  Jurassic Manusela Carbonate BANGGAI Tiaka Jurassic Bobong Sandstone Jurassic Buya Marine shale Early Miocene Tomori Limestone Early. Miocene Salodik Shale & carbonate Late Miocene Matindok Marine shale Thrust anticline Late Miocene Mtindok Sandstone

  Abadi Mid. Jurassic Plover Sandstone Early. Jurassic Plover eq. Marine shale Early Cretaceous Echuca Shoals shale Normal Fault TIMOR Bayu-Undan Mid.Jurassic Elang Sandstone Mid.Jurassic Elang Sandstone Early Cretaceous Echuca Shoals shale Plover Sandstone Plover Sandstone

  (Surjono& Wijayanti, 2012)

  

JURASSIC SEQUENCE PLAYS IMPORTANT ROLE !!

  Content :

  1. Introduction

  2. Tectonic setting and structural elememnts

  3. Tectonostratigraphy

  4. Case study : Timor- Tanimbar Trough ( basin modeling for tectonic collision and hydrocarbon generation)

  5. Conclusion

  

……… Petroleum geology

SOURCE ROCK Is it just from Mid Jura Plover source only? How about

• older (Triassic or Pre-Triassic) or younger (Cretaceous) sequence ? If just only from Mid Jura Plover source, how about its

• distribution inside of the Eastern Indonesian region ?

  What causes maturation within Greater Timor Trough

>region ? Depth-dependant or Overburden thickness- dependant ? Is there just enough charging from Mid Jura Plover

POTENTIAL SOURCE ROCKS

  Echuca Shoals claystone (Late Jurassic-Early Cretaceous) Type III source rock of Echuca Shoals with very good TOC content and HI around 80 mg/g

  Plover Shale (Early-Middle Jurassic) Type III source rock of Plover shale with poor-good TOC content and HI around 150 mg/g

  Mt. Goodwin and Cape Londonderry shale (Permo-Triassic) ? Type

  III source rock of Triassic carbonaceous shale-coal with good to excellent TOC content and high HI

POSSIBILITY OF THE PALEOZOIC SOURCE ROCK

   Potential source rock intervals in North Australia:

   Wessel Group (Neoproterozoic)

   Goulburn Group (Ordovician-Cambrian),  Arafura Group (Devonian)  Kulshill Group equivalent (Permo- Carboniferous).

CHARACTERISTIC (TROUBADOUR -1)

  low potential for oil Mostly high potential ga s w indow MID JURA PLOVER SOURCE ROCK

MID JURA PLOVER SOURCE ROCK

  Type III Low HI <135mgHC/gTOC TOC up to 1.7%

SOURCE ROCKS CHARACTERISTICS (ABADI-1)

  Two Potential Source Rocks 

  Formation/Age Organic Richness HC Potential Hydrogen Index Thermal Maturity (TOC wt.%) (mgHC/gm rock) (HI) (% Ro) Wangarlu/Late Cretaceous very poor to good Poor to moderate Low to moderate Immature-Early mature (0.07 – 1.27)

  (0.37 - 3.40) (42 - 268) (0.40 - 0.65) Jamieson/Early Cretaceous Negligible to poor NA NA Early Mature (0.13 -0.28 )

  (0.55) Echuca Shoals/Early Cretaceous Very good Poor to moderate Low Early Mature (2.21-2.67) (2.02 - 2.62) (57-89) (0.57-66) Upper Plover/Middle Jurassic Good-very good Poor to moderate Low Early-Mid Mature (1.94 - 2.67 ) ( 2.13 - 5.02) ( 79 - 153) (0.60 - 0.74) Lower Plover/Middle Jurassic Very good Moderate to good Low Mid Mature (2.49 - 2.61) (2.48 - 5.62) (87 - 143) (0.65 - 0.83)

• Mid Jura Plover : Type III, good to very good TOC, early- mid mature
• Cretaceous Echucha : Type III, very good TOC, early mature

DISTRIBUTION OF PLOVER SOURCE ROCK

  Coastline could be further NW due to no well control Distribution of Plover shale- rich intervals are critical :

• Towards NW (into Indonesia territory), the environment is considered to change to more marine and open  TOC will definitely decrease further NW
• How far is that, still can be debatable because no well control further north than Abadi Field.

  1D- Basin Modeling

  1. Abadi Field and its surrounding ( Masela PSC; Nagura et al., 2003)

  2. West Abadi Area

  3. West Timor Offshore

  1

  2

  1

  2

3 Barber et.al., 2003

  (Charlton, 2004)

  

Regional heat-flow assumption:



  50-60 mW/m2 (after 200 Ma) averaged from Moore et al (1996) and in accordance with INPEX model from Abadi and thermal maturity calibration from several wells 

  70-80 mW/m2 (before 200 Ma) averaged from Moore et al (1996) and thermal maturity calibration from several wells

  Barber aet.al., 2003

• Abadi Gas Field
• + (Collided Australian Passive Margin Setting)
• A-B seismic section ( + estimated Abadi-1 well loc.)

  Tanimbar Trough PW4 PW1 Abadi-1 Well

  Location Abadi-1 Well on S-N seismic section PW1

NW SE

• +

  

1D BASIN HISTORY (MATURITY MODEL)

ABADI-1 WELL

  Gas Window of Plover Fm. Gas Window of Echuca Shoals Fm. Based on Abadi-1 : Both Plover and Echuca SR have already entered gas generation Plover Gas Generation

  69 Ma (Late Cretaceous) Echuca Shoals Gas Generation

  46 Ma (Mid Eocene)

  1D BASIN HISTORY (TEMPERATURE MODEL) ABADI-1 WELL However, only Plover which has already entered gas expulsion Critical : Gas expulsion was not necessesarily occured soon after gas generation Beginning of Plover SR Gas Expulsion:

41 Ma (Late Eocene)

  

Location Pseudo well PW1 on S-N seismic section

PW1

  

N S

Tanimbar Trough

PW4 PW1 PW1

  Maturity model PW1 : Plover Gas Generation Gas generation for Plover on ~ 0.8 (%Ro) @ 50 mya

  PW4

  

Location pseudo well PW4 on seismic section

NE SW

  Maturity model PW4 Plover Gas Generation Paleozoic Gas Generation (?)

  Gas generation for Plover on ~ 0.8 (%Ro) @ 62 mya

PETROLEUM TIME RISK CHART

  West Abadi Area PS 7 PS 3 PS 4 PS 1 PS 2 PS 5 PS 6 PS 8 PS 7 PS 3 PS 2 PS 6 PS 1

  Sediment overburden thickness is getting thinner Maturation-depth VS Thickness , West Abadi

  1D BASIN HISTORY OF PS1 (WEST ABADI)

• Westernmost of the area
• Thinnest overburden rocks
• Quite deep in depth (5173 ft)

  Result : Triassic Gas Generation No Expulsion!

12 Ma (Mid Miocene)

  Triassic Gas Expulsion has not occurred yet

  1D BASIN HISTORY OF PS7 (WEST ABADI)

• Easternmost of the area
• Thickest overburden rocks
• Shallower than PS-1 in depth

  Triassic Gas Generation

65 Ma (Early Paleocene)

  (4860 ft) Plover Gas Generation Result :

30 Ma (Oligocene) Expulsion of Plover SR! Triassic Gas Expulsion

  29 Ma (Late Oligocene) Plover Gas Expulsion

BASIN MODELING IN PW-1 CLOSED TO TIMOR TROUGH

  Plover Gas Generation Plover Gas Expulsion PS-7 Timor Trough

  (deepest area) PW-1

  

NORTHEASTERN OF PS-7

  E W PS 8 PS 6

  Sediment over burden thickness is getting thinner westward  Critical for gas maturation

  PS 8 PS 6 Sediment over burden thickness is getting thinner westward

   Critical for gas maturation

  

Location pseudo well PS6 & PS8 on seismic section

Timor Trough

PW4 PW1 PS6 PS8

  Maturity model PS6 Gas generation for Triassic and Plover sequences has not reached yet

  Triassic Gas Generation Maturity model PS8

  Plover Gas Generation

• Gas generation for Plover on ~ 0.8 (%Ro) @ 64 mya
• Gas generation for Triassic on ~ 0.8 (%Ro) @ 87 mya

  West Timor Offshore

  PS-1 Pseudo well PS-1 located in the Timor Trough. Note the presence of foreland Plio- Pleistocene deposit.

  PS-1 Top of Dombey Lst Depth Map

SE NW

  Plio-Pleistocene deposit? Timor Trough Maturity model PS-1 Triassic Gas Generation

  Plover Gas Generation (included water column)

• Gas generation for Plover on ~ 0.8 (%Ro) @ 16 mya
• Gas generation for Triassic on

Maturity model PS-1 (excluded water column)

  Triassic Gas Generation Plover Gas Generation

• Gas generation for Plover on ~ 0.8 (%Ro) @ 16 mya
• Gas generation for Triassic on

  PS2 Pseudo well PS-2 located in the near south of Timor Trough. Note that Jurassic sequence / Plover equivalent (Callovian sequence) is still intact here.

  PS-2 Top of Dombey Lst Depth Map

  SE NW Timor Trough Plover eq.

  Triassic Gas Generation Maturity model PS-2

  Plover Gas Generation (included water column)

• Gas generation for Plover on ~ 0.8 (%Ro) @ 30 mya
• Gas generation for Triassic on

  Maturity model PS-2 (excluded water column) Triassic Gas Generation Plover Gas Generation

• Gas generation for Plover on ~ 0.8 (%Ro) @ 30 mya
• Gas generation for Triassic on

Pseudo well PS-3 located in the slightly further south of Timor Trough. Note that

  PS-3 Jurassic sequence / Plover equivalent (Callovian sequence) is completely truncated probably due to Valanginian (Early Cretaceous) erosion event. PS-3

  Top of Dombey Lst Depth Map SE NW Timor Trough

  Maturity model PS-3 (included water column)

  Gas generation for Triassic sequences (Mt. Goodwin & Challis) has not reached yet PS-5 Pseudo well PS-5 is constructed because a part of Plover sequence still exist after experiencing intensive Valanginian (Early Cretaceous) erosion event if it compared to PS-2’s.

  PS-5 Top of Dombey Lst Depth Map

  SW NE Plover eq.

  Triassic Gas Generation Maturity model PS-5 (included water column)

  Gas generation for Triassic on ~ 0.8 (%Ro) @ 52 mya

  Discussion : Barber et.al., 2003

  2

  1

  (Charlton, 2004)

  1

  2

  3 1 , 2 , 3 : Estimated location of developing basin modeling

  Slow Overthrusting

Temperature distribution within the overthrust sheet and uverthrusted units

after a slow ( 0.5 cm / year ) overthrusting (Wygrala et al., 1990)

  Rapid Overthrusting

Temperature distribution within the overthrust sheet and uverthrusted units

after a rapid (5 cm / year) overthrusting (Wygrala et al., 1990)

  Content :

  1. Introduction

  2. Tectonic setting and structural elememnts

  3. Tectonostratigraphy

  4. Case study : Timor- Tanimbar Trough ( basin modeling for tectonic collision and hydrocarbon generation)

  5. Conclusion

  Conclusions :  During Paleozoic

• – Mesozoic; eastern Indonesia was part of northern margin of Australian continent, therefore they have similar sediments succession

  

 Tectonic event during that duration mostly were rifting/break up

• –

  of contintent, sedimentary rocks mostly composed by fluviatil

  transition - shallow marines deposits

  

Paleozoic-Mesozoic succession are mostly well preserved in

Sahul shelves including Northwest Australian and Arafura Shelves, and Papua

   Paleozoic-Mesozoic deposits in Australia Shelves mostly a fluviatil-shallow marine deposites, whereas in the foreland basin and trustbelt are deeper marine sediments

   Tertiary deposits in whole Eastern Indonesia reflects an complex tectonic interaction among Australia-Eurasia-Pacifics Plates movements. Sedimentary rocks ranging from deep

  Conclusions :

 Petroleum systems in Eastern Indonesia occured mainly in

  Mesozoic deposits in which potential source rock as prime element mainly developed

 It seems likely that onset Mesozoic source rock maturation

relate to tectonic collision/deformation (Early Tertiary in

eastern and Late Tertiary in western of the Timor Trough)

  

Time of gas generation is varies, along passive margin of

NW Australian Shelf to Timor-Tanimbar Trough , depends

on factor controlling geologically setting due to evolution of the basement deformation…???

   Experiences by doing Joint Studies in others Eastern

Indonesia basins suggest that tectonics collision play an

important role to source rock maturation process ;

therefore to understand basin evolution in such areas is

very important

  1. Introduction

  

2. Tectonic setting and structural elements

  3. Tectonostratigraphy Regional Geology Regional Setting & Basin Configuration

  Tectonic Evolution & Rifting Configuration Regional Stratigraphy & Petroleum Elements

Regional Paleogeography & Petroleum System

  4. Case study : Timor-Tanimbar Trough

  5. Conclusion