Play System from the Last Decade Discoveries in Indonesia Basins*
By
Brahmantyo K. Gunawan1, Sunjaya E. Saputra1, M. Kusuma Utama1, Cipi Armandita1, and Johnson A. Paju1
Search and Discovery Article #10153 (2008)
Posted August 21, 2008
*Adapted from oral presentation at AAPG Annual Convention, San Antonio, Texas, April 20-23, 2008
1
Exploration Division of Planning Department, Executive Agency for Upstream Oil & Gas Business Activities Republic of Indonesia
(brahmantyokg@bpmigas.com)
Abstract
In the past 10 years of hydrocarbon exploration history in Indonesia, there are several significant hydrocarbon discoveries. Generally,
the play concept has moved to the deeper target and older reservoir. Several new play concepts for the Eastern Indonesia area are thin-
skinned thrust system in the turbidites in the Kalimantan deepwater, Miocene reef play in the Sulawesi area, and Jurassic sand in
Papua and East Timor gap. In East Java basin there are two explorations targets that have been pursued for the last 10 years; they are
Oligo-Miocene reef and volcaniclastic Pliocene sediments. Meanwhile in the Sumatra area the target has changed into the deeper
target, which is Oligo-Miocene syn-rift sediments.
The successful discoveries have resulted in other companies learning from them and increasing their exploration activities in the past
five years by developing new concepts in their blocks or acquiring new blocks in nearby areas. (Mahakam deep water block discovery
has been resulted in other discoveries in the surrounding area, including in Tarakan deepwater area.)
The new play exploration strategy, by defining the new play concept from lessons learned from relatively recent discoveries, has
become the current model in the exploration activities. Therefore, understanding the play concept in new discoveries will immediately
upgrade the opportunity to find hydrocarbons.
PLAY SYSTEM FROM THE LAST DECADE
DISCOVERIES IN INDONESIA BASINS
Brahmantyo K. Gunawan*
Sunjaya E. Saputra*
M. Kusuma Utama*
Cipi Armandita*
Johnson A. Paju*
*Exploration Division of Planning Departement
Executive Agency for Upstream Oil & Gas Bussiness Activities Republic of Indonesia
Presented at 2008 AAPG Annual Convention & Exhibition
San Antonio, April 21th 2008
CONTENT
Introduction
Indonesian Unconventional Play Types Criteria
Unconventional Play Types in Indonesia
Indonesian Discoveries in Last Decade
Unexplored Potential Area
Conclusion
INTRODUCTION
INDONESIAN
EXPLORATION HISTORY PERIODS
1. Dutch Government (1865 – 1940)
Exploration by Dutch Government started in 1865 and first exploration well drilled 1872
First oil field discovery (Telaga Said, North Sumatera) 1885
Exploration target defined by outcrop mapping and shallow drilling technology
2. After Indonesian Independence (until early 1970)
Commercial working area operated by several companies
Discovered Duri, Talang Akar, Minas Field using simple exploration methods and increased the
production, lifting up to 1,000,000 BPOD
3. Early 1970
Start of applied subsurface 2D seismic technology
Production lifting increased up to 1,600,000 BOPD
4. 1980 – 1990
Fluctuation of HC Production (lowest in mid1980 and gradually increased until1990)
2D and deep target drilling applied
mostly productive fields located in back-arc & deltaic passive margin settings
5. 1990 – now
Old fields started to depleted
2D / 3D and drilling technology improvement
trigger to find other targets (unconventional)
INDONESIAN TERTIARY BASIN
UNCONVENTIONAL PLAY TYPES
INDONESIA WORKING AREA
Tertiary Basin 60
Working Area 167
Production Block 58
Exploration Block 109
PLAY TYPES
In general, the exploration targets in Indonesia before 1990 are situated in Western Area and
mostly discoveries were in Neogene Back-Arc Basin and Passive Margin Deltaic Settings,
called Indonesian Conventional (classic) Play Types, Including :
1. Classic Shallow Target
2. Classic Clastics
3. Classic Carbonates
4. Classic Stratigraphic & Combination
Thus Indonesian Unconventional Play Types are play types besides the conventional types
as mentioned above.
The successful unconventional plays have been explored from 1990; they are in :
1. Deep Oligo-Miocene ~ Rift Phase Clastics (5)
2. Deep Oligo-Miocene ~ Carbonate (6)
3. Deep water clastics (Pro-Delta) (7)
4. Volcaniclastics (8)
5. Pre-Tertiary & Basement (9)
6. Collision Tectonic Setting Complex (10)
SUMATERA BACK-ARC
DEEP CLASTIC PLAY
Pematang and Talang Akar
Formation (Paleogene Age)
Mostly Sumateran; NEOGENE
surrounding area produces
from Neogene (Duri,
3 GUF/ ABF
Bekasap, Bangko & Arun) 2
GUF/ ABF 1 1
5
5
Paleogene syn-rift phase 4
LTAF PALEOGENE
(deeper target) has potential Basement 6
6
to find more HC reserves LTAF
LTAF
Basement
Basement
EAST JAVA AREA
DEEP CARBONATE & CLASTIC PLAY
EAST JAVA AREA
MIO-PLIOCENE VOLCANiCLASTIC PLAY
Foreland Volcaniclastic source KE-
KE-11C KE-
KE-11A MIO-PLIOCENE DEPOSITIONAL
SRIKANDI VOLCANICLASTIC MODEL
KE-
KE-11G
GRATI-
GRATI-1
GIGIR-
GIGIR-1
Inner Shelf
KE-
KE-11E
Self
? Middle Shelf
MS1-
MS1-1
BD-
BD-1
shelf
ponded
deposit lf
he
e r s ea
t
ou ok S
shale diapirs rd b
wa m
to at Lo
on a N
cti re
ire e a
D op
sl
S N
KALIMANTAN DEEP WATER
PRO-DELTA SAND PLAY
Success of
deepwater play in
Indonesia was firstly
shown by
exploration efforts
of Unocal and its
partners in the
Lower Kutei – North
Makassar Basin.
Mahakam
Delta
A number of fields
have been
discovered in Lower
Kutei – North
Makassar Basin
since the late
1990s, including :
Merah Besar, West
Seno, Gendalo,
Gandang, Gula,
Gada, Ranggas,
and Gehem.
EASTERN INDONESIA /
AUSTRALIAN CONTINENTAL RELATED
(PASSIVE CONTINENTAL MARGIN & COLLISION PLAY)
Bintuni Basin ;
Tomori Area ; Collision-Related Play in Miocene Carbonate Reservoir ; Salawati Basin ; Old Oil & Gas Discoveries in The Pre-Tertiary
First Discovery in 1999 ; Total Estimated Reserve 3.0 TCFG and 65 Miocene Carbonate Reservoir First Discovery in
MMBC (D. Hasanusi et.al., 2004)
1991 ;
Middle Jurassic
Sandstone
Seram Area ; Reservoir ;
Old Oil Discoveries Total Reserves
at Collision- Potential 24 TCFG
Related Play in (Larry J. Casarta
Cenozoic and et. al., 1998)
Jurassic
Carbonate Central Range of
Reservoir Papua ; Collision-
Related play in Upper
Jurassic Sandstone
Reservoir ;
Non-Commercial oil
discoveries (1998)
Timor Area ;
Old Gas
Discoveries in
Collision-Related Abadi Field
Play in Jurassic (Bonaparte Basin) ;
Sandstone First Discovery in
Reservoir 2000 ;
Middle Jurassic
Sandstone Reservoir ;
Preliminary Estimated
Reserves 5 TCFG
(H. Nagura et. Al.,
2003)
Principal Tectonic Elements Map of Eastern Indonesia shows the related Australian Continent in transparent red colour
(Modified from Nilandroe & Baraclough,2003)
Indonesian Discoveries
in Last Decade
1998 – 2007 DISCOVERIES
< 100 MMBOE
100 - 500 MMBOE
500 - 1000 MMBOE
1000 - 1500 or up to 1500 MMBOE
DISCOVERY RESERVES BY PLAY TYPE
Play Types:
1 – Classic Shallow Target
2 – Classic Clastics
3 – Classic Carbonates
4 – Classic Stratigraphic & Combination
5 – Deep Oligo-Miocene ~ Rift Phase Clastics
6 – Deep Oligo-Miocene ~ Carbonate
7 – Deep Water Clastics (pro-delta)
8 – Volcaniclastics
9 – Pre-Tertiary & Basement
10 – Collision Setting
1 2 3 4 5 6 7 8 9 10
-
500
1,000
1,500
2,000
2,500
ARU
BANGGAI
BINTUNI
CENTRAL
SUMATERA
EAST JAVA
OIL (MMBO)
KUTAI
NW JAVA
BCFG
S. MAKASSAR
SALAWATI
NUMBER OF DISC
SUNDA
DISCOVERY BY BASIN
SOUTH
SUMATERA
TARAKAN
W. NATUNA
0
5
10
15
20
25
30
35
40
45
50
RESERVES vs NUMBER OF DISCOVERY
Play Types:
1 – Classic Shallow Target
4000.00 2 – Classic Clastics 70
3 – Classic Carbonates
4 – Classic Stratigraphic & Combination
3500.00 5 – Deep Oligo-Miocene ~ Rift Phase Clastics
6 – Deep Oligo-Miocene ~ Carbonate 60
7 – Deep Water Clastics (pro-delta)
3000.00 8 – Volcaniclastics
NUMBER OF DISCOVERY
9 – Pre-Tertiary & Basement 50
10 – Collision Setting
MMBO / MMBOE
2500.00
40
2000.00
30
1500.00
20
1000.00
500.00 10
0.00 0
1 2 3 4 5 6 7 8 9 10
P L A Y T Y P E S
OIL (MMBO) GAS (MMBOE) NUMBER OF DISCOVERY
DRILLING
Many Frontier “Deep Water” Basins of Indonesia Remain Unexplored
producing (16)
discovery, non producing (8)
New Opportunities !
no discovery (14)
no drilling (22)
deep water basins (31 basins)
Awang H. Satyana – frontier exploration (Dec. 2007)
CONCLUSION
Why Unconventional Type ?
Oil production from mature field is declining.
New reserve addition from conventional (classic) play
type is minor. No significant replacement of reserves
that are being reduced by HC production.
Unconventional play type discoveries, which are ready to
develop, give larger HC new reserves.
Pre-Tertiary, related to collision with Australian plate,
contributed the most of HC reserves in last decade and
needmore exploration efforts.
Some frontier basins that have unconventional play
types may trap “big fish” (high risk, high reward as
opposed to low risk, low reward).
THANK YOU
TERIMA KASIH
Special Thanks :
Deputy of Planning BPMIGAS
Mr. Achmad Lutfi
Head of Exploration Division BPMIGAS
Mr. Bob Yulian
Head of Exploration Region I, II and III BPMIGAS
Mrs. Nugrahani, Mr. Indro Purwaman, and Mr. Djumlati
Mr. Awang Harun Satyana and Mr. Elan Biantoro for Technically Contribution
Total E&P Indonesie
PetroChina International
