FROM NON-ECONOMIC INTO PRODUCING FIELD, A CASE STUDY IN KETALING BARAT FIELD, INDONESIA

Convention Bandung 2004 (CB2004)
The 33rd Annual Convention & Exhibition 2004

Indonesian Association of Geologist
Horizon Hotel, 29-30 Nov, 1 Oct 2004, Bandung

FROM NON-ECONOMIC INTO PRODUCING FIELD,
A CASE STUDY IN KETALING BARAT FIELD,
INDONESIA

Bob W.H. Adibrata(1), Y. Hirosiadi(2), E. Septama(3), A. Rachmanto(4)

1bobwikan@pertamina.com, 2yosihiro@pertamina.com, Geology Section, Technology Support Division,
Pertamina Upstream, Kwarnas Bld 15th Fl, Jl. Medan Merdeka Timur No. 6, Jakarta 10110 INDONESIA
3erlangga@pertamina-sumbagteng.com, Exploitation Section, Pertamina DOH Sumbagteng, Bajubang, Jambi
36611, INDONESIA
4ambar@pertamina-dohsbs.com, Recent address: Exploitation Section, Pertamina DOH Sumbagsel, Prabumulih,
Sumatera Selatan, INDONESIA

Abstract

Focus of this study is re-activity of a non-economic field into production by combining
old vintage 2D seismic data with current 3D seismic data, supporting with archival,
conventional log data and limited sidewall core and thin section analysis. The
reservoir consists of bioclastic wackestone overlying by coral bindstone in the Upper
Miocene Equivalent of Baturaja Formation, at Ketaling Barat field, Jambi, Indonesia.
The objective of this study is to evaluate and test a multiple attribute analysis
whereby carbonate facies can be determined and to characterize the distribution of
potential carbonate reservoir.

Introduction

Ketaling Barat field is located 5 km East of Jambi, Jambi Province, Indonesia (Figure
1). Activities in this field started in 1959 by Dutch’s NIAM N.V., by drilling 3 wells,
Ketaling 1, 2 and 3, which mainly based on geological field work in the surrounding
area. From those three wells, only Ketaling-2 gave respond with gross of 220 bbl fluid
per day (95% water). With the unsatisfactory result, this field was then abandoned as
a non-economic field for about 40 years. The first 2D seismic data acquisition taken
in 1982, and the vintage set was then re-processed in 2000 and re-interpretation was
held during the same year, with the result of Ketaling Barat (KTB)-04 that has been
drilled in 2001. The appraisal well of KTB-04 gave a significant result of 3600 BOPD,
with no water. Lithology variation between KTB-04 and previous wells, confer the
idea that there are two different stages in carbonate development in this area,
defined as Phase-1 and Phase-2. Phase-1 is platform carbonate where oil produced
from KTB-04, and Phase-2 is reefal carbonate, where oil from Ketaling-2 came from.
Four other wells has been drilled during 2001-2002 period, KTB-05 (Phase-1
reservoir, 1.5 MMSCF), KTB-06 (Phase-2 reservoir, 420 BOPD, 70 % water, 0.5
MMSCF), KTB-07 (Dry hole), KTB-08 (Phase-1 reservoir, Oil show, Technical
problem, P&A). Highly variation in result which represents reservoir heterogeneity,
lead to a mini pilot project (2 x 4 sq. km) of 3D seismic acquisition and processing
that was conducted in 2003 to enhance reservoir characterization.

Improved interpretation has achieved using 3D data volume. The Equivalent of
Baturaja Formation can be determined more clearly into two different stages. The two
stages, Phase-1 and Phase-2 has been mapped respectively. Phase-1 developed as
an isolated platform directly on top of basement, controlled by normal fault, spread out throughout the area with average thickness of 35 meter. Phase-2 developed as
reefal build-up facies, distributed mostly in the center of Ketaling Barat field, with
average thickness of 45 meter. Paleomorphology also worked as the main control on
carbonate development and distribution in the area.