scholarly journals FLOW UNITS DETERMINATION USING FLOW ZONE INDICATOR FOR CARBONATE RESERVOIR

2018 ◽  
Vol 3 (2) ◽  
pp. 93-100
Author(s):  
Abdul Haris ◽  
Agus Riyanto ◽  
Tri Aji Adi Harsanto ◽  
Ambar Rachmanto ◽  
Adang Sukmatiawa

In the last few years, the use of flow unit technique in the oil and gas industry has shown a great deal of success. Porosity and permeability from wire-line log and special core data analysis (SCAL) along with its cementation exponent value were integrated to characterize the reservoir in terms of pore volume caused by facies changing. In this work, we determine flow unit of the carbonate reservoir, which is applied to the Northwest Java Basin Field, Indonesia by performing the flow unit analysis, which allows approximating absolute permeability. Furthermore, the quantity and the flow unit of the reservoir rock is also determined to identify the secondary porosity. To reduce the level of uncertainty, wire-line logs data were validated with core data before it is used to interpret the reservoir. Subsequently, the result can be extrapolated to un-cored wells. Our experiment shows that flow units can be determined reliably from the integration between porosity and permeability, which have defined two different rock types in term of flow unit zone. The correlation of the flow units between wells leads to the definition of reservoir quality.

2021 ◽  
Author(s):  
E. P. Putra

The Globigerina Limestone (GL) is the main reservoir of the seven gas fields that will be developed in the Madura Strait Block. The GL is a heterogeneous and unique clastic carbonate. However, the understanding of reservoir rock type of this reservoir are quite limited. Rock type definition in heterogeneous GL is very important aspect for reservoir modeling and will influences field development strategy. Rock type analysis in this study is using integration of core data, wireline logs and formation test data. Rock type determination applies porosity and permeability relationship approach from core data, which related to pore size distribution, lithofacies, and diagenesis. The analysis resulted eight rock types in the Globigerina Limestone reservoir. Result suggests that rock type definition is strongly influenced by lithofacies, which is dominated by packstone and wackestone - packstone. The diagenetic process in the deep burial environment causes decreasing of reservoir quality. Then the diagenesis process turns to be shallower in marine phreatic zone and causes dissolution which increasing the reservoir quality. Moreover, the analysis of rock type properties consist of clay volume, porosity, permeability, and water saturation. The good quality of a rock type will have the higher the porosity and permeability. The dominant rock type in this study area is RT4, which is identical to packstone lithofasies that has 0.40 v/v porosity and 5.2 mD as average permeability. The packstone litofacies could be found in RT 5, 6, 7, even 8 due to the increased of secondary porosity. It could also be found at a lower RT which is caused by intensive cementation.


2021 ◽  
Vol 62 (3) ◽  
pp. 29-36
Author(s):  

Permeability and porosity are essential parameters for estimating hydrocarbon production from reservoir rocks. They are combined in an additional factor, the Flow Zone Index (FZI), which is the basis for defining the hydraulic flow unit (HFU). Each HFU is a homogeneous section of a reservoir rock with stable parameters that allow for media flow. Hydraulic flow units are determined from the porosity and permeability of core or well logs. The simple statistical methods are applied for HFU classification and then improve permeability prediction. This paper also shows how to quickly apply the global hydraulic elements (GHE) method for HFU classification. The methodology is tested on the Miocene formation of a deltaic facies from the Carpathian Foredeep in South-Eastern Poland.


2018 ◽  
Vol 36 (5) ◽  
pp. 1136-1156 ◽  
Author(s):  
Yuanhua Qing ◽  
Zhengxiang Lü ◽  
Xiandong Wang ◽  
Xiuzhang Song ◽  
Shunli Zhang ◽  
...  

The oil and gas in the Palaeogene lacustrine carbonate rock reservoirs in the Bohai Sea accumulated during several periods. The reservoir porosity formed during each period affected the degree of accumulation that occurred. In this paper, the percentages of particles, authigenic minerals and pores in the reservoir bed were calculated with the statistical method of microstructure analysis. The formation time was determined with an isotopic analysis of the authigenic carbonate minerals and the homogenization temperature of the gas–liquid inclusions. The percentages of the primary intergranular pores that formed during the different stages were recovered based on the compaction features both before and after the formation of the major authigenic minerals. The evolution of porosity was thus described quantitatively and chronologically, employing the percentages of the residual primary intergranular pores, visceral cavity pores and dissolved pores at the different burial depths. The results indicate that in the initial sediments of the reservoir rock, the primary intergranular porosity was 32.4%. During the early burial stage, the total reservoir porosity increased by up to 46.9%, due to the addition of another type of primary pore, namely visceral cavity pores, which were generated from the decomposition of bioclasts. During the late, deep burial stage, the compaction reduced only 8.2% of the porosity, due to the support of the pore-lining dolomite precipitating during the early stage. Authigenic minerals occupied 12.6% of the porosity, and the dissolution created the secondary porosity by 3.8%. Good preservation of the visceral cavity pores and the growth of the pore-lining dolomites during the early stages are the major factors leading to the high reservoir porosity. The quantitative and chronological characteristics of the reservoir porosity evolution could be described accurately. The prediction of reservoir beds can be better guided than in previously reported methods by applying high resolution microscopic quantitative analysis technology and authigenic mineral timing analysis technology.


Author(s):  
V. Sultanov ◽  
L. Sultanov

The complex results of petrophysical testing of rocks, taken from prospecting-development wells of Duvanni-deniz, Sangachal-deniz, Bulla-deniz, Garasu and etc. areas, where the sediments of productive stratum are widely expanded, have been given. Average values of granulometric composition of rocks of productive unit of the above areas by the section have been recounted. The problem of dependence of permeability on porosity and depth was solved. Dependence between physical parameters for the individual kinds of rocks, dependence between physical properties and material structures are established. The results of various petrophysical research methods show that the filtration capacitance properties, in general, deteriorate with depth. However, in certain cases, in clay and carbonate rocks, reservoir properties can improve, due to the appearance of secondary porosity under relatively stringent thermobaric conditions. The histograms, which consist of average values of granulometric composition of productive stratum rocks when crossing some places of archipelago are constructed, the problems of dependence of permeability on porosity and depth were solved. The researches showed, that the physical process of the same- named and same-aged features rocks change in the result of geological-physical processes, getting different values. It's noticed, that the porosity and permeability are increasing from north-west to south-east by changing lithological composition.


Author(s):  
Handoyo Handoyo ◽  
M Rizki Sudarsana ◽  
Restu Almiati

Carbonate rock are important hydrocarbon reservoir rocks with complex texture and petrophysical properties (porosity and permeability). These complexities make the prediction reservoir characteristics (e.g. porosity and permeability) from their seismic properties more difficult. The goal of this paper are to understanding the relationship of physical properties and to see the signature carbonate initial rock and shally-carbonate rock from the reservoir. To understand the relationship between the seismic, petrophysical and geological properties, we used rock physics modeling from ultrasonic P- and S- wave velocity that measured from log data. The measurements obtained from carbonate reservoir field (gas production). X-ray diffraction and scanning electron microscope studies shown the reservoir rock are contain wackestone-packstone content. Effective medium theory to rock physics modeling are using Voigt, Reuss, and Hill.  It is shown the elastic moduly proposionally decrease with increasing porosity. Elastic properties and wave velocity are decreasing proporsionally with increasing porosity and shally cemented on the carbonate rock give higher elastic properties than initial carbonate non-cemented. Rock physics modeling can separated zones which rich of shale and less of shale.


2019 ◽  
Vol 35 (4) ◽  
pp. 531-563 ◽  
Author(s):  
Asefe Mousavi Moghadam ◽  
Mahsa Baghban Salehi

AbstractWettability alteration (WA) of reservoir rock is an attractive topic in the upstream oil and gas industry, for the improvement of hydrocarbon production. Novel methods and chemicals that may change the wetting state of reservoir rock to water-wet have highly attracted petroleum researchers’ attention. Use of nanoparticles might be matured enough in different branches of sciences but in WA is still young, which increased in recent decades. This review paper presents a comprehensive review on WA, especially in terms of nanoparticle application in increasing oil recovery. Therefore, the areas of controversy of two rock types (carbonate and sandstone) as a main element in WA are discussed. A selection of reviewed nanoparticle types, preparation methods, and effective factors was also investigated. Moreover, two main methods of WA, static and dynamic, are highlighted. Although these methods have been discussed in many reviews, a clear classification form of these has not been considered. Such comprehensive arrangement is presented in this review, specifically on nanoparticle application. Moreover, coreflooding tests of different fluid types and injection scenarios are discussed. The review indicates promising use of nanoparticles in increasing ultimate oil recovery. It was hoped the current review paper can provide useful related reference to study WA via nanoparticle application.


2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Alibi Kilybay ◽  
Bisweswar Ghosh ◽  
Nithin Chacko Thomas

In the oil and gas industry, Enhanced Oil Recovery (EOR) plays a major role to meet the global requirement for energy. Many types of EOR are being applied depending on the formations, fluid types, and the condition of the field. One of the latest and promising EOR techniques is application of ion-engineered water, also known as low salinity or smart water flooding. This EOR technique has been studied by researchers for different types of rocks. The mechanisms behind ion-engineered water flooding have not been confirmed yet, but there are many proposed mechanisms. Most of the authors believe that the main mechanism behind smart water flooding is the wettability alteration. However, other proposed mechanisms are interfacial tension (IFT) reduction between oil and injected brine, rock dissolution, and electrical double layer expansion. Theoretically, all the mechanisms have an effect on the oil recovery. There are some evidences of success of smart water injection on the field scale. Chemical reactions that happen with injection of smart water are different in sandstone and carbonate reservoirs. It is important to understand how these mechanisms work. In this review paper, the possible mechanisms behind smart water injection into the carbonate reservoir with brief history are discussed.


Water ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 579
Author(s):  
Bole Gao ◽  
Fei Tian ◽  
Renfang Pan ◽  
Wenhao Zheng ◽  
Rong Li ◽  
...  

Hydrothermal dolomite paleokarst reservoir is a type of porous carbonate reservoir, which has a secondary porosity and can store a large amount of oil and gas underground. The reservoir is formed by magnesium-rich hydrothermal fluids during the karstification and later stages of the transformation. Due to the strong heterogeneity and thin thickness of hydrothermal dolomite paleokarst reservoirs, it is a real challenge to characterize the spatial distribution of the reservoirs. In this paper, we studied the hydrothermal dolomite paleokarst reservoir in the Wolonghe gasfield of the eastern Sichuan Basin. First, based on detailed observations of core samples, the characteristics and storage space types of the dolomite reservoir were described. Secondly, the petrophysical parameters of the paleokarst reservoirs were analyzed, and then the indicator factor for the dolomite reservoirs was established. Thirdly, using the time–depth conversion method, the geological characteristics near boreholes were connected with a three-dimensional (3D) seismic dataset. Several petrophysical parameters were predicted by prestack synchronous inversion technology, including the P-wave velocity, S-wave velocity, P-wave impedance, and the hydrothermal dolomite paleokarst reservoir indicator factor. Finally, the hydrothermal dolomite paleokarst reservoirs were quantitatively predicted, and their distribution model was built. The 3D geophysical characterization approach improves our understanding of hydrothermal dolomite paleokarst reservoirs, and can also be applied to other similar heterogeneous reservoirs.


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