A Quantitative Approach To Characterize Porosity Structure From Borehole Electrical Images and Its Application in a Carbonate Reservoir in the Tazhong Area, Tarim Basin

Summary For a carbonate reservoir that has low porosity, its validity cannot simply be measured by its total porosity. Therefore, one must find more-effective porosity parameters to indicate reservoir validity. Two parameters that reflect the porosity spectrum's shape are proposed in this paper to characterize the porosity structure from borehole electrical images. One is the length of the right-porosity spectrum (LRPS), and the other is the root mean square (RMS) of the right-porosity spectrum (RMSRPS). Subsequently, the validity of a carbonate reservoir was considered by use of these two parameters. The logging evaluation, processing, and interpretation of multiple wells in a fractured/vuggy reservoir with low porosity in the Tarim Basin indicate that these two parameters reflect the variation of pore structures better than conventional methods, and they agree better with the well-test results.

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Nano- to Millimeter Scale Morphology of Connected and Isolated Porosity in the Permo-Triassic Khuff Formation of Oman

Geosciences ◽

10.3390/geosciences10010007 ◽

2019 ◽

Vol 10 (1) ◽

pp. 7 ◽

Cited By ~ 3

Author(s):

Jörg Smodej ◽

Laurent Lemmens ◽

Lars Reuning ◽

Thomas Hiller ◽

Norbert Klitzsch ◽

...

Keyword(s):

Pore Size ◽

Ion Beam ◽

Total Porosity ◽

Oil And Gas Industry ◽

Effective Porosity ◽

Carbonate Reservoir ◽

Size Spectrum ◽

Pore Connectivity ◽

Rock Types ◽

Laboratory Techniques

Carbonate reservoirs form important exploration targets for the oil and gas industry in many parts of the world. This study aims to differentiate and quantify pore types and their relation to petrophysical properties in the Permo-Triassic Khuff Formation, a major carbonate reservoir in Oman. For that purpose, we have employed a number of laboratory techniques to test their applicability for the characterization of respective rock types. Consequently, a workflow has been established utilizing a combined analysis of petrographic and petrophysical methods which provide the best results for pore-system characterization. Micro-computed tomography (µCT) analysis allows a representative 3D assessment of total porosity, pore connectivity, and effective porosity of the ooid-shoal facies but it cannot resolve the full pore-size spectrum of the highly microporous mud-/wackestone facies. In order to resolve the smallest pores, combined mercury injection capillary pressure (MICP), nuclear magnetic resonance (NMR), and BIB (broad ion beam)-SEM analyses allow covering a large pore size range from millimeter to nanometer scale. Combining these techniques, three different rock types with clearly discernible pore networks can be defined. Moldic porosity in combination with intercrystalline porosity results in the highest effective porosities and permeabilities in shoal facies. In back-shoal facies, dolomitization leads to low total porosity but well-connected and heterogeneously distributed vuggy and intercrystalline pores which improves permeability. Micro- and nanopores are present in all analyzed samples but their contribution to effective porosity depends on the textural context. Our results confirm that each individual rock type requires the application of appropriate laboratory techniques. Additionally, we observe a strong correlation between the inverse formation resistivity factor and permeability suggesting that pore connectivity is the dominating factor for permeability but not pore size. In the future, this relationship should be further investigated as it could potentially be used to predict permeability from wireline resistivity measured in the flushed zone close to the borehole wall.

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Evaluation of Well-Test Results and the Potential for Basin-Center Gas in the Colulmbia Basin, Central Washington

Data Series ◽

10.3133/ds2184fo ◽

2008 ◽

Author(s):

Matthew Wilson ◽

Thaddeus S. Dyman ◽

Steven M. Condon

Keyword(s):

Test Results ◽

Well Test

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Technical efficiency of pesticide application on tomato, chinese cabbage and cauliflower in simpang empat sub-district Karo Regency

E3S Web of Conferences ◽

10.1051/e3sconf/20185200045 ◽

2018 ◽

Vol 52 ◽

pp. 00045

Author(s):

Sri Fajar Ayu ◽

Destanul Aulia

Keyword(s):

Technical Efficiency ◽

Chinese Cabbage ◽

Quantitative Method ◽

Protective Device ◽

Test Results ◽

Pesticide Application ◽

Vegetable Farmers ◽

The Right ◽

North Sumatra ◽

Mild Toxicity

Prior research by authors on the use of pesticides and their impact on 75 vegetable farmers in Simpang Empat subdistrict, Karo district, North Sumatra showed that 60% of respondents applied pesticides in excess of the packaging instructions. Respondents were also found not to use a complete protective device. Almost 70% of respondents have mild toxicity complaints, and based on blood cholinesterase levels are also found most respondents have mild toxicity. Pesticide residue test results also found 0.728 residues of chlorpyrifos and 0.321 profenofos in vegetables produced in this area. This led to continued review by checking the technical efficiency in the use of pesticides. The method used is a quantitative method with the Data Envelope Analysis (DEA) approach to analyze technical efficiency of pesticide on each commodity. The population is the whole vegetable farmer who grew tomatoes, Chinese cabbage and cauliflower at the time of the study. The entire population is used to be a sample of 35 tomato and cauliflower farmers and 20 Chinese cabbage farmers. The results of the study indicate that the uses of pesticide as production inputs on tomato commodities, Chinese cabbage and cauliflower are not technically efficient. It is suggested to farmers to use pesticide input according to the rules, proper dosage, on target, on time, the right way so that pesticide used is technically efficient.

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Multi-scale evaluation of fractured carbonate reservoir and its implication to sweet-spot optimization: A case study of Tazhong oilfield, Central Tarim Basin, China

Energy Reports ◽

10.1016/j.egyr.2021.05.017 ◽

2021 ◽

Vol 7 ◽

pp. 2976-2988

Author(s):

Siyu Chen ◽

Yingjin Wang ◽

Junyang Guo ◽

Qinglin He ◽

Xinran Yin

Keyword(s):

Tarim Basin ◽

Carbonate Reservoir ◽

Sweet Spot ◽

Scale Evaluation ◽

Multi Scale ◽

Fractured Carbonate

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Forced Fold Amplitude and Sill Thickness Constrained by Wireline and 3-D Seismic Data Suggest an Elastic Magma-Induced Deformation in Tarim Basin, NW China

Minerals ◽

10.3390/min11030293 ◽

2021 ◽

Vol 11 (3) ◽

pp. 293

Author(s):

Wei Tian ◽

Xiaomin Li ◽

Lei Wang

Keyword(s):

Tarim Basin ◽

Seismic Data ◽

Inelastic Deformation ◽

Northwest China ◽

Well Log ◽

Total Thickness ◽

Nw China ◽

Seismic Method ◽

Two Parameters ◽

Outer Area

Disparities between fold amplitude (A) and intrusion thickness (Hsill) are critical in identifying elastic or inelastic deformation in a forced fold. However, accurate measurements of these two parameters are challenging because of the limit in separability and detectability of the seismic data. We combined wireline data and 3-D seismic data from the TZ-47 exploring area in the Tarim Basin, Northwest China, to accurately constrain the fold amplitude and total thickness of sills that induced roof uplift in the terrain. Results from the measurement show that the forced fold amplitude is 155.0 m. After decompaction, the original forced fold amplitude in the area penetrated by the well T47 ranged from 159.9 to 225.8 m, which overlaps the total thickness of the stack of sills recovered by seismic method (171.4 m) and well log method (181.0 m). Therefore, the fold amplitude at T47 area is likely to be elastic. In contrast, the outer area of the TZ-47 forced fold is characterized by shear-style deformation, indicating inelastic deformation at the marginal area. It is suggested that interbedded limestone layers would play an important role in strengthening the roof layers, preventing inelastic deformation during the emplacement of intrusive magma.

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High Resolution Sequence Stratigraphy Analysis in a Carbonate Reservoir from Borehole Resistivity Image: a Case Study from Tarim Basin, West China

10.2523/iptc-17411-ms ◽

2014 ◽

Author(s):

S. Yang ◽

C. Xiao ◽

G. Wei ◽

I. Le Nir

Keyword(s):

High Resolution ◽

Sequence Stratigraphy ◽

Tarim Basin ◽

Carbonate Reservoir ◽

West China ◽

High Resolution Sequence Stratigraphy ◽

Resistivity Image

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Friction-Instability: A New Design Parameter for Brakes

Journal of Engineering for Industry ◽

10.1115/1.3428066 ◽

1971 ◽

Vol 93 (4) ◽

pp. 1225-1228 ◽

Cited By ~ 1

Author(s):

W. L. Starkey ◽

T. G. Foster ◽

S. M. Marco

Keyword(s):

Quality Control ◽

Coefficient Of Friction ◽

Design Parameter ◽

Control Device ◽

Experimental Facility ◽

Test Results ◽

Effective Manner ◽

The Coefficient Of Friction ◽

Brake Lining ◽

The Right

A new design parameter, friction-instability, is defined in this paper. Friction-instability is a variation in the coefficient of friction which may occur at any time during the life of a brake lining. A friction-index is defined which measures this variation. A lining which has a high friction index may tend to cause an automobile to swerve either to the right or to the left. A unique experimental facility is described by means of which the friction-instability characteristics of brake linings can be measured. Test results using this facility are presented and interpreted. The friction-index is proposed as a new parameter which should be taken into consideration when brakes are designed and, developed. This index should be particularly useful as a quality control device to insure that machines which use mass-produced braking systems will perform in a safe and effective manner.

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Tight Jurassic Carbonate Reservoir Characterization and Fluid Typing Identification by Integrating Magnetic Resonance, Elemental Spectroscopy and Micro-Resistivity Image Data in Umm Ross Field, West Kuwait, Case Study

10.2118/207883-ms ◽

2021 ◽

Author(s):

Said Beshry Mohamed ◽

Sherif Ali ◽

Mahmoud Fawzy Fahmy ◽

Fawaz Al-Saqran

Keyword(s):

Magnetic Resonance ◽

Reservoir Characterization ◽

Clay Content ◽

Effective Porosity ◽

Carbonate Reservoir ◽

High Resistivity ◽

Permeability Index ◽

Rock Quality ◽

Porosity And Permeability ◽

Bulk Volume

Abstract The Middle Marrat reservoir of Jurassic age is a tight carbonate reservoir with vertical and horizontal heterogeneous properties. The variation in lithology, vertical and horizontal facies distribution lead to complicated reservoir characterization which lead to unexpected production behavior between wells in the same reservoir. Marrat reservoir characterization by conventional logging tools is a challenging task because of its low clay content and high-resistivity responses. The low clay content in Marrat reservoirs gives low gamma ray counts, which makes reservoir layer identification difficult. Additionally, high resistivity responses in the pay zones, coupled with the tight layering make production sweet spot identification challenging. To overcome these challenges, integration of data from advanced logging tools like Sidewall Magnetic Resonance (SMR), Geochemical Spectroscopy Tool (GST) and Electrical Borehole Image (EBI) supplied a definitive reservoir characterization and fluid typing of this Tight Jurassic Carbonate (Marrat formation). The Sidewall Magnetic resonance (SMR) tool multi wait time enabled T2 polarization to differentiate between moveable water and hydrocarbons. After acquisition, the standard deliverables were porosity, the effective porosity ratio, and the permeability index to evaluate the rock qualities. Porosity was divided into clay-bound water (CBW), bulk-volume irreducible (BVI) and bulk-volume moveable (BVM). Rock quality was interpreted and classified based on effective porosity and permeability index ratios. The ratio where a steeper gradient was interpreted as high flow zones, a gentle gradient as low flow zones, and a flat gradient was considered as tight baffle zones. SMR logging proved to be essential for the proper reservoir characterization and to support critical decisions on well completion design. Fundamental rock quality and permeability profile were supplied by SMR. Oil saturation was identified by applying 2D-NMR methods, T1/T2 vs. T2 and Diffusion vs. T2 maps in a challenging oil-based mud environment. The Electrical Borehole imaging (EBI) was used to identify fracture types and establish fracture density. Additionally, the impact of fractures to enhance porosity and permeability was possible. The Geochemical Spectroscopy Tool (GST) for the precise determination of formation chemistry, mineralogy, and lithology, as well as the identification of total organic carbon (TOC). The integration of the EBI, GST and SMR datasets provided sweet spots identification and perforation interval selection candidates, which the producer used to bring wells onto production.

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