Three-dimensional Magnetotelluric Crustal Model of High Agri Valley seismic area to identify and to quantify the resistivity variation in depth

2020 ◽  
Author(s):  
Anna Eliana Pastoressa ◽  
Marianna Balasco ◽  
Juanjo Ledo ◽  
Pilar Queralt ◽  
Gerardo Romano ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Regularization Parameter ◽  
Three Dimensional ◽  
Correct Choice ◽  
Structural Features ◽  
Fault System ◽  
Gas Field ◽  
Period Range ◽  
Stress Regime ◽  
Resistivity Variation

<p>The High Agri Valley (HAV) is an axial zone of the Southern Apennines thrust belt chain with a strong seismogenic potential as shown by different stress indicators and space geodesy data that suggest an NE-SW extensional stress regime still active. Moreover, the HAV hosts the Europe’s largest onshore oil and gas field, which give it further strategic importance.</p><p>There is a certain ambiguity concern the causative fault of the large event (M=7.0) occurred in 1857 in Agri Valley, although two well-documented fault systems are recognised as potentially seismogenic: the Monti della Maddalena Fault System (MMFS) and the Eastern Agri Fault System (EAFS).</p><p>With the aim to bring new information on identification and characterization of the principal structures, on the fluids distribution and their possible relationship with the developed of kinematics in upper fragile crust, several multiscale and multidisciplinary surveys are currently running in the HAV. Here we present the first results of a 3D Magnetotelluric (MT) investigation composed of 58 MT soundings in the period range [10<sup>-2</sup> Hz, 10<sup>3</sup> Hz] which cover an area of approximately of 15 km x 30 km. All the 3D results were obtained by using the 3D inversion conde ModEM: Modular EM Inversion Software.</p><p>The work carried out so far has been mainly focused on the definition of the best mesh to adopt, both in terms of cell size and orientation, and on the correct choice of the inversion parameters: resistivity of the starting model, smoothing model parameter, minimum error floor attributed to the data, regularization parameter (trade-off).</p><p>The 3D MT preliminary model obtained shows a good agreement with 2D models previously realized using a part of the same dataset and defines the main geo-structural features of the HAV.</p><p>The resistivity variations in HAV subsurface will be jointly interpreted with accurate seismic data collected by seismic broadband network INSIEME (composed by 8 stations distributed throughout the Agri Valley) and other available geophysical and geological data.</p><p>The interconnection between the conductivity and seismicity information will be useful to implement the knowledge on the role that fluids play in fault zones and in earthquake processes. </p>

Seismic attribute for characterization and prediction of carbonate faulted karst reservoirs in Tarim Basin, China

2021 ◽  
pp. 1-36
Author(s):  
Zhiwei Xiao ◽  
Li Wang ◽  
Ruizhao Yang ◽  
Dewei Li ◽  
Lingbin Meng
Keyword(s):  
Tarim Basin ◽  
Oil And Gas ◽  
Prediction Method ◽  
Strike Slip ◽  
Fault System ◽  
Bright Spot ◽  
Upper Ordovician ◽  
Reservoir Prediction ◽  
Seismic Attribute ◽  
Gas Field

An ultradeep, faulted karst reservoir of Ordovician carbonate was discovered in the Shunbei area of the Tarim Basin. Fractured-cavity reservoirs buried beneath the large thickness of upper Ordovician mudstone were formed along the fault-karst belts. The hydrocarbon accumulation in these reservoirs is controlled by the fault system, and the oil-gas accumulation was affected by karstification and hydrothermal reformation. Previous studies and 2D modeling revealed that the reservoirs had “bright spot” amplitude responses like “string beads,” and they have developed along the strike-slip faults. However, describing such a complex fault-controlled karst system is still a difficult problem that has not been well addressed. We have sought to instruct the attribute expression of faulted karst reservoirs in the northern part of the Tarim Basin. We applied coherence and fault likelihood (FL) seismic attributes to image faults and fractures zones. We then used a trend analysis method to calculate the residual impedance from the impedance of the acoustic inversion, using the fact that residual impedance has higher lateral resolution in reservoir predictions. Finally, we integrated the coherence, FL, and residual impedance attributes into a new seismic attribute, the “fault-vuggy body,” with a certain fusion coefficient. The fault-vuggy body attribute establishes a connection between faults and karst cavities. This method could help in the characterization and prediction of carbonate faulted karst reservoirs. Available drilling data were used to validate that the fused fault-vuggy body attribute was an effective reservoir prediction method. As the seismic sections and slices along the layer help delineate, the distribution of bright spots and strike-slip faults indicates that the main strike-slip fault zones are the most favorable reservoirs in the Shunbei Oil and Gas Field.

Geomechanical analysis of horizontal wells in terms of stability for drilling — A case study from the Peri-Baltic Syneclise

2021 ◽  
Vol 40 (11) ◽  
pp. 805-814
Author(s):  
Michał Kępiński ◽  
Pramit Basu ◽  
David Wiprut ◽  
Marek Koprianiuk
Keyword(s):  
Horizontal Well ◽  
Oil And Gas ◽  
Horizontal Wells ◽  
Microseismic Monitoring ◽  
Earth Model ◽  
Gas Field ◽  
Horizontal Section ◽  
Stress Regime ◽  
Geomechanical Analysis

This paper presents a shale gas field geomechanics case study in the Peri-Baltic Syneclise (northern Poland). Polish Oil and Gas Company drilled a vertical well, W-1, and stimulated the Silurian target. Next, a horizontal well, W-2H, drilled the Ordovician target and partially collapsed. The remaining interval was stimulated, and microseismic monitoring was performed. A second horizontal well, W-3H, was drilled at the same azimuth as W-2H, but the well collapsed in the upper horizontal section (Silurian). A geomechanical earth model was constructed that matches the drilling experiences and well failure observations found in wells W-1, W-2H, and W-3H. The field was found to be in a strike-slip faulting stress regime, heavily fractured, with weak bedding contributing to the observed drilling problems. An analysis of safe mud weights, optimal casing setting depths, and optimal drilling directions was carried out for a planned well, W-4H. Specific recommendations are made to further enhance the model in any future studies. These recommendations include data acquisition and best practices for the planned well.

scholarly journals Using Response Surface Analysis to Estimate Time of The Gas-Water Contact Lift in Yamburg Gas Field Conditions

2021 ◽  
Vol 87 (3) ◽  
pp. 105-112
Author(s):  
Mugisho Joel Bacirheba ◽  
Tanoh Boguy Eddy Martial ◽  
Mirsamiev Narzullo Abdugaforovich ◽  
Madumarov Mukhriddin Mukhammadjon Ugli
Keyword(s):  
Response Surface ◽  
Surface Analysis ◽  
Contact Time ◽  
Oil And Gas ◽  
Three Dimensional ◽  
Response Surface Analysis ◽  
Outcome Variable ◽  
Model Parameters ◽  
Gas Field ◽  
Water Contact

Like many of the fields in northwest Siberia, the Yamburg oil and gas condensate field is in the final production stages. This, therefore, results in an accumulation of a large amount of formation water in the inflow at the bottom of the well. Response surface analysis is used as a new technique to gain a detailed understanding of the relationships between combinations of two predictor variables and an outcome variable. This approach was applied to the Yamburg field to estimate the time of the gas-water contact, considered as the result variable, by taking into account two groups of predictive variables which correspond to the reservoirs grouped by their lithological characteristics. The results of the predicted gas-water contact time were compared to the expected gas-water contact time, the data of which were taken into account for the study. Using the model parameters as well as the three-dimensional response surface, which was constructed to facilitate and improve the interpretation of the results, it was then possible to predict the gas-water contact time under certain conditions.

Methods for making stereoslides and -prints, with freeze-etched olfactory epithelium as example

1984 ◽  
Vol 42 ◽  
pp. 704-705
Author(s):  
Bert Ph. M. Menco ◽  
Ido F. Menco ◽  
Frans L.T. Verdonk
Keyword(s):  
Electron Microscope ◽  
Olfactory Epithelium ◽  
Three Dimensional ◽  
Supporting Cell ◽  
Structural Features ◽  
Extensive Study ◽  
Sprague Dawley ◽  
Freezing Method ◽  
Respiratory Epithelia ◽  
Three Dimensional Presentation

Previously we presented an extensive study of the distributions of intramembranous particles of structures in apical surfaces of nasal olfactory and respiratory epithelia of the Sprague-Dawley rat. For the same structures these distributions were compared in samples which were i) chemically fixed and cryo-protected with glycerol before cryo-fixation, after excision, and ii)ultra-rapidly frozen by means of the slam-freezing method. Since a three-dimensional presentation markedly improves visualization of structural features micrographs were presented as stereopairs. Two exposures were made by tiling the sample stage of the electron microscope 6° in either direction with an eucentric goniometer. The negatives (Agfa Pan 25 Professional) were reversed with Kodak Technical Pan Film 2415 developed in D76 1:1. The prints were made from these reversed negatives. As an example tight-junctional features of an olfactory supporting cell in a region where this cell conjoined with two other cells are presented (Fig. 1).

scholarly journals Investigations of polyethylene of raised temperature resistance service performance using autoclave test under sour medium conditions

e-Polymers ◽  
2021 ◽  
Vol 21 (1) ◽  
pp. 346-354
Author(s):  
Guoquan Qi ◽  
Hongxia Yan ◽  
Dongtao Qi ◽  
Houbu Li ◽  
Lushi Kong ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Mechanical Performance ◽  
Three Dimensional ◽  
Service Performance ◽  
Degree Of Branching ◽  
Temperature Resistance ◽  
Temperature Conditions ◽  
Dimensional Network ◽  
Gas Medium ◽  
Better Than

Abstract The chapter deals with the performance evaluation of the polyethylene of raised temperature resistance (PE-RT) and polyethylene (PE) using autoclave test under sour oil and gas medium conditions. The analyses of performance changes showed that PE-RT has good media resistance at 60°C. As the temperature increases, its mechanical properties decrease, accompanied by an increase in weight. Comparative analyses showed that no matter what temperature conditions are, PE-RT media resistance is better than PE80. The better media resistance of PE-RT depends on its higher degree of branching. Short branches are distributed between the crystals to form a connection between the crystals, thereby improving its heat resistance and stress under high-temperature conditions. PE-RT forms an excellent three-dimensional network structure through copolymerization, ensuring that it has better media resistance than PE80. However, the mechanical performance will be attenuated due to the high service temperature.

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