cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
Wulandari
Contact Email
jurnal.lemigas@esdm.go.id
Phone
+6221-7394422
Journal Mail Official
jurnal.lemigas@esdm.go.id
Editorial Address
Jl. Ciledug Raya Kav. 109, Cipulir, Kebayoran Lama, Jakarta Selatan 12230
Location
Kota adm. jakarta selatan,
Dki jakarta
INDONESIA
Scientific Contributions Oil and Gas
Published by LEMIGAS
ISSN : 20893361     EISSN : 25410520     DOI : -
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Energy
The Scientific Contributions for Oil and Gas is the official journal of the Testing Center for Oil and Gas LEMIGAS for the dissemination of information on research activities, technology engineering development and laboratory testing in the oil and gas field. Manuscripts in English are accepted from all in any institutions, college and industry oil and gas throughout the country and overseas.
Arjuna Subject : Energi (semua kategori) - Teknologi Bahan Bakar
Articles 5 Documents
 1 
Search results for , issue "Vol 29 No 3 (2006)" : 5 Documents clear
PLEISTOCENE PALYNOLOGY OF EAST JAVA Eko Budi Lelono
Scientific Contributions Oil and Gas Vol 29 No 3 (2006)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.29.3.1027

Abstract

This study is a part of geological investigation on Pleistocene sediment in East Java in order to evaluate hydrocarbon potential within this sediment of this area. The area of study is located in the on-shore East Java (Figure 1). It is financially supported by the oil company as this is commercial work done by LEMIGAS Exploration Department. Therefore, data used in this paper will be incompletely presented as they are confidential. The name of the studied wells and their precise locations are hided in this paper. Data used in this study derives from three wells namely R, S and T. Three different disciplines are applied in this study including palynology, micropaleontology and nannoplankton analyses which are useful for crosschecking purposes. Apparently, the integration of these analyses gains accurate interpretation of stratigraphy and depositional environment. The area of study is in East Java Basin which can be classified as a classical back-arc basin. During Pleistocene, the area of study was marked by regional uplift and the cessation of open marine sedimentation (LEMIGAS, 2005). Therefore Pleistocene age was dominated by non-marine deposition. Generally, this type of sediment is separated from the underlying layer by an unconformity (LEMIGAS, 2005). Most Pleistocene sediment consists of volcanoclastic as a result of volcanic activity which related to uplifting period. It is possible that volcanic activity was responsible for the burning of grass as indicated by the occurrence of charred Gramineae cuticles. The previous investigations on Pleistocene sediment showed the domination of grass pollen of Monoporites annulatus which suggested the expansion of dry climate during Pleistocene glacial maxima. The pollen diagram from Lombok Ridge produced by van der Kaas (1991a) proves the domination of Gramineae pollen during Pleistocene (Figure 2). The period of dry climate (glacial climate) is characterised by abundant Gramineae pollen, whilst the period of wetter climate (interglacial climate) is indicated by an increase of coastal and mangrove palynomorphs, but greatly reduced frequencies of Graminaae pollen (Morley, 2000). In addition, Rahardjo et al. (1994) referred to the high abundance of Monoporites annulatus to propose Pleistocene pollen zone of M. annulatus (Figure 3).
ON GOING COALBED METHANE (CBM) DEVELOPMENT IN THE SOUTH SUMATRA BASIN Imam B. Sosrowidjojo
Scientific Contributions Oil and Gas Vol 29 No 3 (2006)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.29.3.1028

Abstract

Coalbed methane (CBM) is going to be an important facet of the nation’s energy mix. It is expected to contribute in importance energy back up for the future. CBM is natural gas, a clean-burning energy source that is reservoired in a coal seam. CBM is formed during the coal maturation process and may in a free or adsorbed state in coal seams in adjacent formations. CBM is dominantly methane but lesser concentrations of carbon dioxide and nitrogen, compare to conventional natural gas. However, in most cases, CBM is of sufficient quality for sale directly into natural gas transmission lines with a limited amount of moisture removal.CBM as natural gas has numerous benefits to include direct selling, well suited as city gas, electricity generation, boiler fuel, transportation fuel, and for many types of chemical industries feed. Beside CBM replaces coal to be greatly reduces the production of acid rain and other forms of air pollution, the development of CBM has benefitial for coal miners. It can contribute to improved mining safety as well as it can help reduce construction costs.CBM is probably one of the promising alternative fuel energy resources in Indonesia that its presence is actual and comparable with the existing coal resources in any potential basin. Unlike some well in developed countries where commercialization of methane production from coal seam has been developed, coals direct mined in Indonesia seem to be more attractive and preferable technique to supply the consumer demand of energy. This is because coal mines serve direct products, less complicated technology, low exploration risks, easy recovery, relatively low cost but quick yields and already have wide market. Consequently, people have overlooked the existence of consisting huge potential methane gas in coals.However, petroleum exploration data throughout Indonesia suggest that increasing coal rank occurs rapidly with depth in many basins and that gas kicks are almost common associated with some coal seams below 200 m depth. In addition, world CBM exploration now has shifted towards lower rank settings (i.e, vitrinite reflectance between 0.3% and 0.6% Ro). In Indonesia, thick coals generally are found at greater depth, higher in rank and therefore are expected to be more productive (Saghafi and Hadiyanto, 2000).LEMIGAS is currently conducting a drilling program to study the feasibility of CBM production in South Sumatra. The domain of the work is in the Muaraenim Formation (Upper – Middle Palembang). The coal sequences were deposited during Late Miocene. We believe that a big effort is extremely essential to establish the reserve and economic potential of CBM in South Sumatra to later extent to Indonesia.
A LABORATORY STUDY TO IMPROVE ACID STIMULATION IN SANDSTONES Septi Anggraeni; Junita Trivianty; Bambang Widarsono
Scientific Contributions Oil and Gas Vol 29 No 3 (2006)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.29.3.1029

Abstract

The main purpose of acidizing is to improve well productivity. Acids are useful for this reason because of their ability to dissolve undesired formation minerals and materials which may either be intrinsic in nature or be introduced into the formation during the processes of drilling, completion, and production. The effectiveness of acids in improving productivity in a particular well essentially depends on an accurate analysis of the problem and the selection of acid.Prudent judgment in acid to be used should be confirmed by laboratory tests. Apart from the analysis on the nature of the formation damage itself, acid selection should be based on study of reservoir rocks mineralogy and characteristics in general and accordingly the relevant material/minerals to be dissolved or removed. Improper diagnostics may result in inefficient, and even damaging, acidizing. Various studies have been conducted in this highlight (e.g. Crowe, 1984; Gidley, 1971; Crowe in Economides and Nolte, 1989; Daccord in Economides and Nolte, 1989; Ali, 1981; and Piot and Perthuis in Economides and Nolte, 1984).Those studies conducted in the past reveal that in comparison the success ratio of acidizing for limestone reservoir is almost 90%, whereas for sandstone reservoir the success ratio is only 30%. Undoubtedly, this disparity in success ratios is caused by the fact that appropriate acids dissolve limestones more properly due to limestones generally simpler mineral composition and by the fact that sandstones usually have more complex mineralogy hence providing less simple materials to dissolve. From this point Those studies conducted in the past reveal that in comparison the success ratio of acidizing for limestone reservoir is almost 90%, whereas for sandstone reservoir the success ratio is only 30%. Undoubtedly, this disparity in success ratios is caused by the fact that appropriate acids dissolve limestones more properly due to limestones generally simpler mineral composition and by the fact that sandstones usually have more complex mineralogy hence providing less simple materials to dissolve. From this point
SEISMIC-DERIVED ROCK TRUE RESISTIVITY (Rt ) REVISITED. PART II: REFORMULATION USING WYLLIE’S TIME-AVERAGE MODEL Bambang Widarsono; Merkurius. F. Mendrofa
Scientific Contributions Oil and Gas Vol 29 No 3 (2006)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.29.3.1030

Abstract

This paper is the second of a three-part presentation. As highlighted in the previous paper (Part I, Widarsono & Mendrofa, 2006), the main objective of the study is to re-evaluate the potential of acoustic impedance as a source of resistivity data. This essentially came from the very idea of extracting information of resistivity (Rt ), data that plays a very important role in the determination of water saturation in reservoir, from seismic-derived acoustic impedance (AI).As observed in the past view years, there have been a lot of efforts devoted to the extraction of water saturation information from seismic. However, as Widarsono & Mendrofa (2006) put it, most of the efforts were mainly based on pattern recognition activities with little attention was given to the theoretical aspects of relationships between seismic signals and water saturation. The work reported in this threepart presentation is concentrated more as re-establishing (a reformulation of works reported in Widarsono & Saptono, 2003; 2004) the theoretical relationship between resistivity and acoustic impedance.In the Part I (Widarsono & Mendrofa, 2006), a reformulation between the classical Gassmann acoustic velocity model and shally sand models of Modified Simandoux and Hossin is presented. In the reformulation, a new resistivity function of acoustic impedance has been established. In principle, whenever acoustic impedance data from seismic has been made available resistivity data for the determination of fluid saturation can be estimated.Despite the theoretical correctness of the resistivity function presented in the Part I, practicallity is not the function’s best aspect. In other words, the resistivity function is not an easy one to be used practically. Various parameters (e.g. matrix moduli) have to be assumed, since the data cannot easily measured even in the laboratory. This is indeed the main reason why gassmann model, and others such as Biot, has not been used much in day-to-day practices such as log interpretation for porosity determination.Being aware of such difficulties, in 1954 M.R.J. Wyllie et al proposed their “time average” model (named after its proportional averaging of pore fluid, rock matrix, and shale transit time values to represent transit time of a fluid-filled porous medium) for any practical uses related to P-wave velocity in porous media. Due to its simplicity, the model, as well as its subsequent modifications, has been used extensively since then in some areas especially in log analysis for porosity determination. Considering this simplicity aspect, this three-part study also adopted Wyllie “time average” model into its reformulation works. This Part II paper presents the formulation using Wyllie and the two shally sand models following the same manner that was adopted and presented in the Part I paper.Summarily, the objectives of the works presented in this paper are:- To establish a model/method to obtain formation rock true resistivity (Rt ) from seismic-derived acoustic impedance (AI),- To provide correction/modification onto previous works reported in Widarsono & Saptono (2003, 2004), and- To provide a simpler alternative to the resistivity function yielded from the reformulation works presented in Part I paper (Widarsono & Mendrofa, 2006)
DRIVEABILITY INDEX OF COMMERCIAL GASOLINE IN ASEAN COUNTRIES A.S. Nasution; E. Jasjfi
Scientific Contributions Oil and Gas Vol 29 No 3 (2006)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/SCOG.29.3.1031

Abstract

Motor gasoline is essentialy a complex mixture of hydrocarbons distilling between about 40°C and 225°C and consisting of compounds generaly in the range C5 to C12. Small amounts of additives are also used to exchange various aspects of the performance of the fuel. Gasoline produced from different refin[1]eries can vary widely in compositions, even at the same octane level.The primary requirement of a gasoline is that should burn smoothly without exploding, under the conditions existing in the combustion chamber of the spark-ignition, so that themaximum amount of useful energy is liberated[1].The volatility of a gasoline has a vital influence on the both performance of a car emission. It affects the way car starts, the time it takes to warm up, the exten to which ice will form in the carburator, causing stalling and other problems; it influences vapour lock in the fuel system and indirectly it determines overall fuel economy. Volatility is a measure of the ability of a fuel to pass from the liquid to the vapour state under varying conditions.In cold weather, cars can take a very significant time to warm-up i.e., be capable of smooth, non-hesitating accelerations without the use of the choke. The fuel parameter that is found to have the grestest influence on warm-up is the mid-boiling range volatility as characterized by for example; the 50 per cent distillation temperature. Even after the car has warmed up, fuel volatility can still have an influence on acceleration time. Low volatility fuels obviously give leaner mixture and as mixtures leaner, acceleration performance can fall off quite rapidly.The fraction of the fuel that influences acceleration behaviour to the greatest extent is in the mid and to a lesser extent the higher boiling range. Thus, the 50% distillation temperature, sometimes together with the 90% distillation, must be controlled to ensure optimum acceleration behaviour. The factors which influence vapour lock is the volatility characteristics of the fuel. The degree to which a fuel is liable to give vapour lock depends mainly on its front end volatility. A number of different front-end volatility parameters have been used to define the vapour locking tendency of a fuel, such as RVP, percentage evaporated at 70°C, the 10 and 15% slope of the distillation curve, the vapour/liquid ratio at a given temperature and pressure. These distillation characteristics affect the following performance characteristics: starting, vapour lock and driveability.ASTM D4814-98a the standard specification for Automotive Spark-Ignition Engine Fuel has included Driveability Index as an item of performance requirement of the fuel. The inclusion of the parameter is to provide control of distillation parameters that influence cold start and warm up driveabilities.

Page 1 of 1 | Total Record : 5

 1 

Filter by Year

2006 2006


Reset
Filter By Issues
All Issue Vol 49 No 1 (2026) Vol 48 No 4 (2025) Vol 48 No 3 (2025) Vol 48 No 2 (2025) Vol 48 No 1 (2025) Vol 47 No 3 (2024) Vol 47 No 2 (2024) Vol 47 No 1 (2024) Vol 46 No 3 (2023) Vol 46 No 2 (2023) Vol 46 No 1 (2023) Vol 45 No 3 (2022) Vol 45 No 2 (2022) Vol 45 No 1 (2022) Vol 44 No 3 (2021) Vol 44 No 2 (2021) Vol 44 No 1 (2021) Vol 43 No 3 (2020) Vol 43 No 2 (2020) Vol 43 No 1 (2020) Vol 42 No 3 (2019) Vol 42 No 2 (2019) Vol 42 No 1 (2019) Vol 41 No 3 (2018) Vol 41 No 2 (2018) Vol 41 No 1 (2018) Vol 40 No 3 (2017) Vol 40 No 2 (2017) Vol 40 No 1 (2017) Vol 39 No 3 (2016) Vol 39 No 2 (2016) Vol 39 No 1 (2016) Vol 38 No 3 (2015) Vol 38 No 2 (2015) Vol 38 No 1 (2015) Vol 37 No 3 (2014) Vol 37 No 2 (2014) Vol 37 No 1 (2014) Vol 36 No 3 (2013) Vol 36 No 2 (2013) Vol 36 No 1 (2013) Vol 35 No 3 (2012) Vol 35 No 2 (2012) Vol 35 No 1 (2012) Vol 34 No 3 (2011) Vol 34 No 2 (2011) Vol 34 No 1 (2011) Vol 33 No 3 (2010) Vol 33 No 2 (2010) Vol 33 No 1 (2010) Vol 32 No 3 (2009) Vol 32 No 2 (2009) Vol 32 No 1 (2009) Vol 31 No 3 (2008) Vol 31 No 2 (2008) Vol 31 No 1 (2008) Vol 30 No 3 (2007) Vol 30 No 2 (2007) Vol 30 No 1 (2007) Vol 29 No 3 (2006) Vol 29 No 2 (2006) Vol 29 No 1 (2006) Vol 28 No 3 (2005) Vol 28 No 2 (2005) Vol 28 No 1 (2005) Vol 27 No 3 (2004) Vol 27 No 2 (2004) Vol 27 No 1 (2004) Vol 26 No 2 (2003) Vol 26 No 1 (2003) Vol 25 No 3 (2002) Vol 25 No 2 (2002) Vol 25 No 1 (2002) Vol 24 No 2 (2001) Vol 24 No 1 (2001) Vol 23 No 3 (2000) Vol 23 No 2 (2000) Vol 23 No 1 (2000) Vol 22 No 2 (1999) Vol 22 No 1 (1999) Vol 21 No 2 (1998) Vol 21 No 1 (1998) Vol 18 No 2 (1995) Vol 18 No 1 (1995) Vol 17 No 1 (1994) Vol 16 No 1 (1993) Vol 15 No 1 (1992) Vol 14 No 2 (1991) Vol 14 No 1 (1991) Vol 13 No 1 (1990) Vol 12 No 1 (1989) Vol 11 No 1 (1988) Vol 10 No 3 (1987) Vol 10 No 2 (1987) Vol 10 No 1 (1987) Vol 9 No 1 (1986) Vol 8 No 2 (1985) Vol 8 No 1 (1985) Vol 7 No 2 (1984) Vol 7 No 1 (1984) Vol 6 No 1 (1983) Vol 5 No 2 (1982) Vol 5 No 1 (1982) More Issue