Redefining Reservoir Architecture of Hydrocarbon-Bearing Ngrayong Formation in Banyu Urip Area:New Insights to Unravel Hidden Potential in East Java Basin

2021 ◽  
Author(s):  
L. O Ahdyar
Keyword(s):  
Deep Water ◽  
Energy Demand ◽  
Carbonate Reservoir ◽  
Reservoir Quality ◽  
New Paradigm ◽  
Thin Sections ◽  
Carbonate Cement ◽  
Reservoir Architecture ◽  
Wide Range ◽  
Clastic Reservoir

Results of Banyu Urip (BU) carbonate exploration, appraisal and development drillings revealed the existence of hydrocarbon-contained in Serravallian deep-water clastic reservoir on top of the primary BU carbonate reservoir. This clastic reservoir is equivalent to the Ngrayong Formation in East Java Basin which is widely known as a mature exploration target and consists of a wide range of depositional environment from fluvio-deltaic (northern part of the Basin) to basin floor (southern part of the basin) with various reservoir quality. However, after a century of exploration activities in East Java Basin, commercial discoveries in the Ngrayong Formation are still considered insignificant (approximately 330 MMboe) (Mazied et al. 2016). This probably due to complex reservoir architecture posted high uncertainty of its reservoir presence, distribution, and quality as well challenging on their dynamic aspects such as un-known hydrocarbon connectivity, un-even contacts and low-deliverability. This paper will present new insights and the potential of Ngrayong clastic opportunity in BU area based on static and dynamic data including BU wells, newly reprocessed 3D seismic data, conventional core and thin sections, as well as integrated geologic and geophysical analyses. Integration of the available dataset suggest the presence of stacked deep water channels and deep water lobes systems. The distribution of stacked channels and lobes seem to be more predictive and widespread, hence providing a better understanding of its reservoir distribution. Furthermore, well data indicates approximately total of 100m net stacked clastic reservoirs consist of mixed carbonate-clastic materials, and have good reservoir pressure connectivity with the carbonate reservoir underneath. This mixed clastic-carbonate system in Ngrayong Formation is diagenetically-altered, and this diagenesis process plays as an important roles in modifying reservoir quality. Although carbonate cement and diagenetic overprint impose challenging reservoir quality prediction, a dissolution creates better reservoir quality, generates excess permeability and produces high flow reservoir. Detail study of reservoir architecture and diagenesis process are critical to better assess volumetric and development opportunity. These key components will open up new paradigm and essential for successful of Ngrayong Formation exploration in East Java Basin in order to contribute to the country’s energy demand.

Reservoir Quality of the Miocene Formation Gas Deposits, Onshore Abu Dhabi

2021 ◽  
Author(s):  
Catherine Breislin ◽  
Laura Galluccio ◽  
Kate Al Tameemi ◽  
Riaz Khan ◽  
Atef Abdelaal
Keyword(s):  
Depositional Environment ◽  
Middle Miocene ◽  
Quality Analysis ◽  
Reservoir Quality ◽  
Carbonate Facies ◽  
Pore System ◽  
Thin Sections ◽  
Reservoir Architecture ◽  
Porosity And Permeability ◽  
Permeability Anisotropy

Abstract Understanding reservoir architecture is key to comprehend the distribution of reservoir quality when evaluating a field's prospectivity. Renewed interest in the tight, gas-rich Middle Miocene anhydrite intervals (Anh-1, Anh-2, Anh-3, Anh-4 and Anh-6) by ADNOC has given new impetus to improving its reservoir characterisation. In this context, this study provides valuable new insights in geological knowledge at the field scale within a formation with limited existing studies. From a sedimentological point of view, the anhydrite layers of the Miocene Formation, Anh-1, Anh-2, Anh-3, Anh-4 and Anh-6 (which comprise three stacked sequences: Bur1, Bur2 and Bur3; Hardenbol et al., 1998), have comparable depositional organisation throughout the study area. Bur1 and Bur2 are characterised by an upward transition from intertidal-dominated deposits to low-energy inner ramp-dominated sedimentation displaying reasonably consistent thickness across the area. Bur3 deposits imply an initial upward deepening from an argillaceous intertidal-dominated to an argillaceous subtidal-dominated setting, followed by an upward shallowing into intertidal and supratidal sabkha-dominated environments. This Bur3 cycle thickens towards the south-east due to a possible deepening, resulting in the subtle increase in thickness of the subtidal and intertidal deposits occurring around the maximum-flooding surface. The interbedded relationship between the thin limestone and anhydrite layers within the intertidal and proximal inner ramp deposits impart strong permeability anisotropy, with the anhydrite acting as significant baffles to vertical fluid flow. A qualitative reservoir quality analysis, combining core sedimentology data from 10 wells, 331 CCA data points, 58 thin-sections and 10 SEM samples has identified that reservoir layers Anh-4 and Anh-6 contain the best porosity and permeability values, with the carbonate facies of the argillaceous-prone intertidal and distal inner ramp deposits hosting the best reservoir potential. Within these facies, the pore systems within the carbonate facies are impacted by varying degrees of dolomitisation and dissolution which enhance the pore system, and cementation (anhydrite and calcite), which degrade the pore system. The combination of these diagenetic phases results in the wide spread of porosity and permeability data observed. The integration of both the sedimentological features and diagenetic overprint of the Middle Miocene anhydrite intervals shows the fundamental role played by the depositional environment in its reservoir architecture. This study has revealed the carbonate-dominated depositional environment groups within the anhydrite stratigraphic layers likely host both the best storage capacity and flow potential. Within these carbonate-dominated layers, the thicker, homogenous carbonate deposits would be more conducive to vertical and lateral flow than thinner interbedded carbonates and anhydrites, which may present as baffles or barriers to vertical flow and create significant permeability anisotropy.

DETRITAL AND AUTHIGENIC MINERALOGY OF THE PRETTY HILL FORMATION IN THE PENOLA TROUGH, OTWAY BASIN: IMPLICATIONS FOR FUTURE EXPLORATION AND PRODUCTION

1995 ◽  
Vol 35 (1) ◽  
pp. 538 ◽  
Author(s):  
B. M. Little ◽  
S. E. Phillips
Keyword(s):  
Reservoir Quality ◽  
Secondary Porosity ◽  
Water Contact ◽  
Thin Sections ◽  
Authigenic Minerals ◽  
Wide Range ◽  
Resistivity Logs ◽  
Exploration And Production ◽  
Reservoir Sandstones ◽  
The Impact

The Pretty Hill Formation in the Penola Trough is a productive gas reservoir in the Katnook, Ladbroke Grove and Haselgrove fields. Thin sections, X-ray diffraction, scanning electron micros­copy and electron microprobe analyses have been used to characterise the mineralogy of core samples from eight wells. The reservoir sandstones are typically fine to medium grained, moderately sorted feldspathic litharenites. Framework grains comprise detrital quartz, feldspars (albite, microcline and anorthite), lithics (dominantly volcanic), mica and accessory minerals. Authigenic minerals of chlorite, laumontite, carbonate, quartz, feldspar, sphene, anatase, glaucony and illite are present in all wells. Kaolinite is restricted to Ladbroke Grove-1. Chlorite, laumontite and carbonate are volumetrically the most important authigenic minerals.There is a wide range in core plug porosity (one to 23 per cent) and permeability (10"3to 103 md) in the reservoir sandstones. In samples with high per­centages of authigenic clays microporosity is im­portant. Regional trends indicate reservoir quality decreases with increasing depth but superimposed on this trend is the influence of the detrital and authigenic mineralogy. Cleaner, coarser sublitharenites and subarkoses have good reservoir char­acteristics but where lithics concentrate in the finer feldspathic litharenites and litharenites deformation of these ductile grains has limited porosity and permeability. Authigenic minerals have both reduced and enhanced reservoir quality. Chlo­rite rims with associated microporosity have decreased the impact of mechanical compaction and inhibited silicification. Pore filling cements of laumontite and carbonate have occluded intergranular pores and replaced grains. Secondary porosity produced by the dissolution of these cements in the gas zones has significantly improved reservoir quality.Other information gained from the mineralogical study could influence future exploration and production. Lack of contrast on resistivity logs between gas and water zones is not due to the mineralogy of the Pretty Hill Formation. However, the restriction of early diagenetic laumontite to the water zones of gas producing wells does indicate the location of the gas-water contact. Laumontite was dissolved from the gas zone by an increase in C02 prior to hydrocarbon migration. Use of acids to enhance permeability in the Pretty Hill Formation should take into account the probable formation damage caused by reactions with the clays. Kaolin- ite could dissolve to produce a silica gel and the high Fe3+ content of the chlorite will result in a gel unless iron chelators are used in the mud acid. The depositional environment of the Pretty Hill Forma­tion has historically been interpreted as braided fluvial stream deposits interfingering with finer grained lacustrine shales and siltstone. However, this model can not explain the presence of glaucony grains, unless the glaucony has been reworked, but there is no unequivocal evidence to support this hypothesis.

scholarly journals Integrated Porosity Classification and Quantification Scheme for Enhanced Carbonate Reservoir Quality: Implications from the Miocene Malaysian Carbonates

2021 ◽  
Vol 9 (12) ◽  
pp. 1410
Author(s):  
Hammad Tariq Janjuhah ◽  
George Kontakiotis ◽  
Abdul Wahid ◽  
Dost Muhammad Khan ◽  
Stergios D. Zarkogiannis ◽  
...  
Keyword(s):  
Total Porosity ◽  
Depositional Environments ◽  
Carbonate Reservoir ◽  
Pore System ◽  
Secondary Porosity ◽  
Rock Classification ◽  
Thin Sections ◽  
Diagenetic Processes ◽  
Wide Range ◽  
Pore Types

The pore system in carbonates is complicated because of the associated biological and chemical activity. Secondary porosity, on the other hand, is the result of chemical reactions that occur during diagenetic processes. A thorough understanding of the carbonate pore system is essential to hydrocarbon prospecting. Porosity classification schemes are currently limited to accurately forecast the petrophysical parameters of different reservoirs with various origins and depositional environments. Although rock classification offers a way to describe lithofacies, it has no impact on the application of the poro-perm correlation. An outstanding example of pore complexity (both in terms of type and origin) may be found in the Central Luconia carbonate system (Malaysia), which has been altered by diagenetic processes. Using transmitted light microscopy, 32 high-resolution pictures were collected of each thin segment for quantitative examination. An FESEM picture and a petrographic study of thin sections were used to quantify the grains, matrix, cement, and macroporosity (pore types). Microporosity was determined by subtracting macroporosity from total porosity using a point-counting technique. Moldic porosity (macroporosity) was shown to be the predominant type of porosity in thin sections, whereas microporosity seems to account for 40 to 50% of the overall porosity. Carbonates from the Miocene have been shown to possess a substantial quantity of microporosity, making hydrocarbon estimate and production much more difficult. It might lead to a higher level of uncertainty in the estimation of hydrocarbon reserves if ignored. Existing porosity classifications cannot be used to better understand the poro-perm correlation because of the wide range of geological characteristics. However, by considering pore types and pore structures, which may be separated into macro- and microporosity, the classification can be enhanced. Microporosity identification and classification investigations have become a key problem in limestone reservoirs across the globe.

scholarly journals The IDEAL household energy dataset, electricity, gas, contextual sensor data and survey data for 255 UK homes

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Martin Pullinger ◽  
Jonathan Kilgour ◽  
Nigel Goddard ◽  
Niklas Berliner ◽  
Lynda Webb ◽  
...  
Keyword(s):  
Survey Data ◽  
Energy Demand ◽  
Secondary Data ◽  
Hot Water ◽  
Power Measurement ◽  
Sensor Data ◽  
Energy Awareness ◽  
Household Energy ◽  
Wide Range ◽  
The Ideal

AbstractThe IDEAL household energy dataset described here comprises electricity, gas and contextual data from 255 UK homes over a 23-month period ending in June 2018, with a mean participation duration of 286 days. Sensors gathered 1-second electricity data, pulse-level gas data, 12-second temperature, humidity and light data for each room, and 12-second temperature data from boiler pipes for central heating and hot water. 39 homes also included plug-level monitoring of selected electrical appliances, real-power measurement of mains electricity and key sub-circuits, and more detailed temperature monitoring of gas- and heat-using equipment, including radiators and taps. Survey data included occupant demographics, values, attitudes and self-reported energy awareness, household income, energy tariffs, and building, room and appliance characteristics. Linked secondary data comprises weather and level of urbanisation. The data is provided in comma-separated format with a custom-built API to facilitate usage, and has been cleaned and documented. The data has a wide range of applications, including investigating energy demand patterns and drivers, modelling building performance, and undertaking Non-Intrusive Load Monitoring research.

scholarly journals Improved imaging and analysis of chlorite in reservoirs and modern day analogues: new insights for reservoir quality and provenance

2018 ◽  
Vol 484 (1) ◽  
pp. 189-204 ◽  
Author(s):  
R. H. Worden ◽  
James E. P. Utley ◽  
Alan R. Butcher ◽  
J. Griffiths ◽  
L. J. Wooldridge ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Analysis Data ◽  
Reservoir Quality ◽  
Phase Identification ◽  
Thin Sections ◽  
Analytical Technique ◽  
Quantitative Mineralogy ◽  
Digital Format ◽  
Scanning Electron

AbstractChlorite is a key mineral in the control of reservoir quality in many siliciclastic rocks. In deeply buried reservoirs, chlorite coats on sand grains prevent the growth of quartz cements and lead to anomalously good reservoir quality. By contrast, an excess of chlorite – for example, in clay-rich siltstone and sandstone – leads to blocked pore throats and very low permeability. Determining which compositional type is present, how it occurs spatially, and quantifying the many and varied habits of chlorite that are of commercial importance remains a challenge. With the advent of automated techniques based on scanning electron microscopy (SEM), it is possible to provide instant phase identification and mapping of entire thin sections of rock. The resulting quantitative mineralogy and rock fabric data can be compared with well logs and core analysis data. We present here a completely novel Quantitative Evaluation of Minerals by SCANning electron microscopy (QEMSCAN®) SEM–energy-dispersive spectrometry (EDS) methodology to differentiate, quantify and image 11 different compositional types of chlorite based on Fe : Mg ratios using thin sections of rocks and grain mounts of cuttings or loose sediment. No other analytical technique, or combination of techniques, is capable of easily quantifying and imaging different compositional types of chlorite. Here we present examples of chlorite from seven different geological settings analysed using QEMSCAN® SEM–EDS. By illustrating the reliability of identification under automated analysis, and the ability to capture realistic textures in a fully digital format, we can clearly visualize the various forms of chlorite. This new approach has led to the creation of a digital chlorite library, in which we have co-registered optical and SEM-based images, and validated the mineral identification with complimentary techniques such as X-ray diffraction. This new methodology will be of interest and use to all those concerned with the identification and formation of chlorite in sandstones and the effects that diagenetic chlorite growth may have had on reservoir quality. The same approach may be adopted for other minerals (e.g. carbonates) with major element compositional variability that may influence the porosity and permeability of sandstone reservoirs.

scholarly journals Depositional, diagenetic and stratigraphic aspects of Macaé Group carbonates (Albian): example from an oilfield from Campos Basin

2015 ◽  
Vol 45 (2) ◽  
pp. 243-258 ◽  
Author(s):  
Juliana Okubo ◽  
Ricardo Lykawka ◽  
Lucas Veríssimo Warren ◽  
Julia Favoreto ◽  
Dimas Dias-Brito
Keyword(s):  
Deep Water ◽  
Carbonate Rocks ◽  
Facies Analysis ◽  
Sedimentary Facies ◽  
Fair Weather ◽  
Thin Sections ◽  
Carbonate Sedimentation ◽  
Diagenetic Processes ◽  
Campos Basin ◽  
Facies Associations

<p>Carbonate rocks from the Macaé Group (Albian) represent an example of carbonate sedimentation related to the drift phase in Campos Basin. This study presents depositional features, integrating them with diagenetic and stratigraphic aspects of the Macaé Group carbonates including the upper part of the Quissamã Formation and the lower part of the Outeiro Formation. Macroscopic analyses in cores and microscopic ones in thin sections allowed the recognition of eleven sedimentary facies - nine of them corresponding to the Quissamã Formation and two of them representing the Outeiro Formation. These facies were grouped into five facies associations. Oolitic grainstones and oncolitic grainstones are interpreted to be deposited in shallow depth probably in shoals above the fair weather wave base. The interbanks between shoals were formed in less agitated waters and characterized by deposition of peloidal bioclastic packstones and wackestones representative of sedimentation in calm waters. Bioclastic packstones and oolitic packstones/wackestones represent allochthonous deposits related to the beginning of the regional drowning that occur in upper Quissamã Formation. Pithonellids wackestones and bioclastic wackestones with glauconite are related to deep water deposits, characteristics of the Outeiro Formation. Post-depositional features revealed the action of diagenetic processes as, micritization, cimentation, dissolution, compaction, dolomitization and recrystallization occurred during the eo- and mesodiagenesis phases. Vertical facies analysis suggests shallowing upward cycles stacked in a sequence progressively deeper towards the top (from the Quissamã Formation to the Outeiro Formation).</p>

scholarly journals Clinical risk management and child mental health

2003 ◽  
Vol 9 (5) ◽  
pp. 319-326 ◽  
Author(s):  
Fiona Subotsky
Keyword(s):  
Mental Health ◽  
Risk Management ◽  
Health Services ◽  
Child Mental Health ◽  
Policy Development ◽  
Clinical Governance ◽  
Clinical Risk Management ◽  
New Paradigm ◽  
Adult Services ◽  
Wide Range

Risk management is a requirement of clinical governance and a new paradigm for child and adolescent mental health services. Issues are different from those of adult services and a wide range need to be considered, which include not only the risk of harm to self, to others and from others but also from the system (by omission or commission) and to the staff. Systematic policy development, using information from audits, complaints, incidents and inquiries, will be helpful and interagency agreements necessary to promote coordination. The complex regulatory framework is discussed.

Sign in / Sign up

Export Citation Format

Share Document