Insights on Fractured Domains in Reservoirs Resulting from Modeling Complex Geology/Structures - Case Study of the Ratana Field in the Potwar Basin, Pakistan

2021 ◽  
Author(s):  
Jean-Christophe Wrobel-Daveau ◽  
Rodney Barracloughy ◽  
Sarah Laird ◽  
Nick Matthies ◽  
Bilal Saeed ◽  
...  
Keyword(s):  
Structural Model ◽  
Structural Complexity ◽  
High Amplitude ◽  
Fracture Pattern ◽  
Geophysical Modeling ◽  
Kinematic Evolution ◽  
Tight Carbonate ◽  
Exploration And Production ◽  
Incremental Strain ◽  
Interpretation Algorithm

Abstract Exploration success in fold-and-thrust belts, like the Potwar petroleum province, is impacted by seismic imaging challenges and structural complexity. Success partly relies on the ability to validate subsurface models and model a range of properties, such as reservoir permeability. This is particularly important in the case of tight carbonate reservoirs such as the Eocene Sakesar Formation, where the recovery of economic quantities of hydrocarbons is conditioned by the presence of fracture-enhanced permeability. This requires the application of geological and geophysical modeling techniques to address these challenges, to minimize uncertainty and drive exploration success. The interpretation and structural validation of the Ratana structure presented here allows the proposal of a consistent and robust structural model even in areas of higher uncertainty in the data, such as along faults. The dynamically updatable, watertight, complex 3D structural framework created for the top Sakesar reservoir was used in combination with an assisted fault interpretation algorithm to characterize the fault and fracture pattern. The results showed a higher density of high amplitude fractures on the flanks of the structure rather than along the hinge. These results are supported by the incremental strain modeling based on the kinematic evolution of the structure. Together, this helped to characterize potential fracture corridors in areas of the seismic volume that previously proved challenging for human driven interpretation. Our results allow us to reduce the uncertainty related to the geometrical characteristics of the reservoir and provide insights into potential exploration well targets to maximize chances of success, suggesting that permeability and hydrocarbon flow may be higher at the margins of the Ratana structure, and not at the crest, which was the focus of previous exploration and production efforts.

scholarly journals Examining the tectono-stratigraphic architecture, structural geometry, and kinematic evolution of the Himalayan fold-thrust belt, Kumaun, northwest India

Lithosphere ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 414-435 ◽  
Author(s):  
Subhadip Mandal ◽  
Delores M. Robinson ◽  
Matthew J. Kohn ◽  
Subodha Khanal ◽  
Oindrila Das
Keyword(s):  
Cross Section ◽  
Structural Model ◽  
Kinematic Model ◽  
Thrust Belt ◽  
Main Central Thrust ◽  
Thrust Sheet ◽  
Balanced Cross Section ◽  
Kinematic Evolution ◽  
Thrust Sheets ◽  
Northwest India

Abstract Existing structural models of the Himalayan fold-thrust belt in Kumaun, northwest India, are based on a tectono-stratigraphy that assigns different stratigraphy to the Ramgarh, Berinag, Askot, and Munsiari thrusts and treats the thrusts as separate structures. We reassess the tectono-stratigraphy of Kumaun, based on new and existing U-Pb zircon ages and whole-rock Nd isotopic values, and present a new structural model and deformation history through kinematic analysis using a balanced cross section. This study reveals that the rocks that currently crop out as the Ramgarh, Berinag, Askot, and Munsiari thrust sheets were part of the same, once laterally continuous stratigraphic unit, consisting of Lesser Himalayan Paleoproterozoic granitoids (ca. 1850 Ma) and metasedimentary rocks. These Paleoproterozoic rocks were shortened and duplexed into the Ramgarh-Munsiari thrust sheet and other Paleoproterozoic thrust sheets during Himalayan orogenesis. Our structural model contains a hinterland-dipping duplex that accommodates ∼541–575 km or 79%–80% of minimum shortening between the Main Frontal thrust and South Tibetan Detachment system. By adding in minimum shortening from the Tethyan Himalaya, we estimate a total minimum shortening of ∼674–751 km in the Himalayan fold-thrust belt. The Ramgarh-Munsiari thrust sheet and the Lesser Himalayan duplex are breached by erosion, separating the Paleoproterozoic Lesser Himalayan rocks of the Ramgarh-Munsiari thrust into the isolated, synclinal Almora, Askot, and Chiplakot klippen, where folding of the Ramgarh-Munsiari thrust sheet by the Lesser Himalayan duplex controls preservation of these klippen. The Ramgarh-Munsiari thrust carries the Paleoproterozoic Lesser Himalayan rocks ∼120 km southward from the footwall of the Main Central thrust and exposed them in the hanging wall of the Main Boundary thrust. Our kinematic model demonstrates that propagation of the thrust belt occurred from north to south with minor out-of-sequence thrusting and is consistent with a critical taper model for growth of the Himalayan thrust belt, following emplacement of midcrustal Greater Himalayan rocks. Our revised stratigraphy-based balanced cross section contains ∼120–200 km greater shortening than previously estimated through the Greater, Lesser, and Subhimalayan rocks.

Plastic Limit Analysis of Perforated Material Under Finite Deformation

2005 ◽  
Author(s):  
Xinjian Duan ◽  
Arnaud Weck ◽  
David S. Wilkinson ◽  
Don R. Metzger
Keyword(s):  
Deformation Theory ◽  
Structural Model ◽  
Cell Model ◽  
Fracture Pattern ◽  
Plastic Strain Rate ◽  
Finite Element Models ◽  
Engineering Strain ◽  
Failure Path ◽  
Plastic Limit Analysis ◽  
Local Cell

In this paper, the fracture pattern of a perforated aluminum sheet is studied experimentally and numerically using finite element models on two different length scales: a full-scale structural and a local cell models based on the large deformation theory. Through appropriate application of boundary conditions, the more efficient local cell model is shown to produce almost the same results as the full structural model. It is also found that the failure path is significantly affected by the loading conditions (uniaxial vs. biaxial) and the hole distribution pattern. By plotting the instantaneous contour of plastic strain rate, the fracture path could clearly be distinguished by the time that the overall engineering strain had reached 3%.

scholarly journals Bone quality evaluation of experimental osteometabolic disease in Pantanal alligators (Caiman yacare) by High Resolution Computerized Microtomography (μCT)

2018 ◽  
Vol 38 (5) ◽  
pp. 981-990 ◽  
Author(s):  
Marciel Becker ◽  
Marcos A. Souza ◽  
Luiz G. Moraes ◽  
Gustavo S. Silva ◽  
Nadia A.B. Antoniassi ◽  
...  
Keyword(s):  
High Resolution ◽  
Bone Quality ◽  
Structural Model ◽  
Bone Structure ◽  
Structural Complexity ◽  
Sun Exposure ◽  
Total Porosity ◽  
Trabecular Thickness ◽  
Balanced Diet

ABSTRACT: Computerized microtomography is the gold standard examination for the evaluation of the three-dimensional bone structure. This experiment was developed to evaluate the structure and bone quality of Caiman yacare with metabolic bone disease using high resolution computerized microtomography (μCT). The animals were distributed into four groups: G1 - hyperphosphatemic diet with sun exposure deprivation (n=4), G2 - hyperphosphatemic diet with sun exposure (n=4), G3 - balanced diet with sun exposure deprivation (n=4), and G4 - balanced diet with exposure to sunlight (n=4). The parameters for the trabecular bone (Trabecular Number, Trabecular Thickness, Trabecular Separation, Bone Pattern Factor, Fractal Dimension, Euler Number, Structural Model Index, Degree of Anisotropy, Eigenvalues 1, 2 and 3, and Centroides X, Y and Z), and cortical bone (Number of Closed Pores, Volume of Closed Pores, Surface of Closed Pores, Closed Porosity, Volume of Open Pores, Open Porosity and Total Porosity). The overall results showed that the structure and bone quality of group G3 and G4 were better than those of groups G1 and G2, and that the diet factor influenced more than the sun exposure factor. The computerized microtomography allowed to evaluate the quality of the cortical and trabecular bones of the Pantanal alligator tibia with osteometabolic disease. The diet and sun exposure factors influenced individually the results of the μCT parameters between the groups, demonstrating the functional and structural complexity. Thus, these parameters can contribute to the interpretation of the mechanical behavior of bones and correlate them with the risk of lesions and fractures associated with osteometabolic diseases.

scholarly journals Reconstruction of a Segment of the UNESCO World Heritage Hadrian’s Villa Tunnel Network by Integrated GPR, Magnetic-Paleomagnetic, and Electric Resistivity Prospections

2019 ◽  
Author(s):  
Annalisa Ghezzi ◽  
Antonio Schettino ◽  
Pietro Paolo Pierantoni ◽  
Lawrence Conyers ◽  
Luca Tassi ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Structural Model ◽  
World Heritage ◽  
High Amplitude ◽  
Electric Resistivity ◽  
Computer Assisted ◽  
Unesco World Heritage ◽  
Field Modelling ◽  
Underground System ◽  
The Magnetic Field

The UNESCO World Heritage Hadrian’s Villa lies over the Colli Albani volcanic district near Rome. Magnetic, paleomagnetic, radar, and electric resistivity surveys were performed in the Plutonium–Inferi sector to detect buried buildings and outline a segment of the underground system of tunnels that link different zones of the villa. In particular, a paleomagnetic analysis of the bedrock unit allowed to accomplish an accurate geomagnetic field modelling and characterize the archaeological sources of the magnetic field anomalies. We used a computer-assisted forward modelling procedure to generate a structural model of the sources of the observed anomalies. The intrinsic ambiguity of the magnetic field modelling was reduced with the support of ground penetrating radar amplitude slices and an analysis of radar and electric resistivity profiles. The bedrock lithology in this area is an ignimbrite tuff characterized by abundant iron oxides. The high-amplitude magnetic anomalies observed in the Plutonium–Inferi area are due to strong bedrock remnant magnetization and susceptibility contrasts between topsoil infill of cavities and the surrounding tuff. The resulting magnetization model of the Plutonium–Inferi complex shows that the observed anomalies are mostly due to the presence of tunnels, skylights and a system of ditches excavated in the tuff.

scholarly journals Identification of gas hydrate on bottom-simulating reflector characteristics with 2D seismic pre-stack time migration of North Bali Waters

2021 ◽  
Vol 944 (1) ◽  
pp. 012004
Author(s):  
I A Sufajar ◽  
H M Manik ◽  
T B Nainggolan ◽  
D Kusnida
Keyword(s):  
Gas Hydrates ◽  
Gas Hydrate ◽  
Oil And Gas ◽  
High Amplitude ◽  
Bottom Simulating Reflector ◽  
Oil And Gas Exploration ◽  
North East ◽  
The North ◽  
Time Migration ◽  
Exploration And Production

Abstract Gas hydrate is a physical compound composed of gas molecules that are formed in a seabed layer characterised by high pressure and low temperature. It is known as one of the alternative non-conventional hydrocarbons besides petroleum and natural gas. One of the identified areas of gas hydrate stability zone is in the North Bali Waters. The North Bali Waters is part of the North East Java Basin, which has oil and gas exploration and production, both conventional and non-conventional. One method of identifying the content of gas hydrates is by looking at the appearance of the Bottom Simulating Reflector (BSR) as shown on the Pre-Stack Time Migrated seismic sections. The detection of gas hydrate zone is determined by the presence of high amplitude, reversed polarity reflection and cross-cut reflection of sedimentary layer. This study aims to determine the existence of a BSR in the waters of North Bali. The procedures for analysing the existence of Bottom Simulating Reflector in this study are pre-processing, processing, and interpretation of 2D marine seismic data. The result shows gas hydrates found with indicated Bottom Simulating Reflector on CDP 35-812 at TWT depth of 1526-1582 ms, characterised by high amplitude-reverse polarity.

scholarly journals Influence of salt in the tectonic development of the frontal thrust belt of the eastern Cordillera (Guatiquía area, Colombian Andes)

2015 ◽  
Vol 3 (4) ◽  
pp. SAA17-SAA27 ◽  
Author(s):  
Vanessa Parravano ◽  
Antonio Teixell ◽  
Andrés Mora
Keyword(s):  
Structural Model ◽  
Salt Tectonics ◽  
Thrust Belt ◽  
Eastern Cordillera ◽  
Salt Migration ◽  
Colombian Andes ◽  
Kinematic Evolution ◽  
Geologic Maps ◽  
History Of ◽  
Tectonic Development

Geologic maps, seismic lines, and data from a dry exploration well were used to develop a new structural model for a segment of the eastern foothills of the Eastern Cordillera of Colombia, emphasizing the role of salt tectonics. Milestones in the deformation history of the Guatiquía foothills were studied by sequential section restoration to selected steps. Uncommon structural geometries and sparse salt occurrences were interpreted in terms of a kinematic evolution in which Cretaceous salt migration in extension produced a diapiric salt wall, which was subsequently welded during the main episodes of the Andean compression, when the salt wall was squeezed generating a large overturned flap. Salt-weld strain hardening resulted in breakthrough thrusting across the overturned flap in late deformation stages. We have evaluated a pattern of salt tectonics previously unrecognized in the foothills thrust belt, which may be significant in other parts of the external Colombian Andes.

Geometry, kinematics and fracture pattern of the Bangestan anticline, Zagros, SW Iran

2011 ◽  
Vol 148 (5-6) ◽  
pp. 964-979 ◽  
Author(s):  
STEFANO TAVANI ◽  
FABRIZIO STORTI ◽  
BAHMAN SOLEIMANY ◽  
MOHAMMAD FALLAH ◽  
JOSEP A. MUÑOZ ◽  
...  
Keyword(s):  
Sedimentary Cover ◽  
Fractured Reservoirs ◽  
Fracture Pattern ◽  
Strike Slip ◽  
Deformation Pattern ◽  
Fold Axis ◽  
Lateral Strike Slip ◽  
Kinematic Evolution ◽  
Bangestan Anticline ◽  
Extensional Structures

AbstractThrust-related anticlines in the Zagros Simply Folded Belt provide excellent exposed analogue structures for fractured reservoirs located in the more external sectors of the belt. In these structures it is possible to study the fracture network attributes and understand their relationships to the folding process, thus gathering fundamental information for fracture modelling in reservoirs. In this work we analyse the mesoscopic deformation pattern of the NW–SE-trending Bangestan anticline (SW Zagros, Iran) and discuss its relationship to the kinematic evolution of the hosting structure. The deformation pattern mostly includes extensional structures and pressure solution cleavages striking parallel to the fold axial trend (i.e. longitudinal), transversal extensional structures, and N–S- and E–W-striking extensional structures (oriented oblique to the fold axis). With the aid of deep wells and a transversal reflection seismic profile, we constructed a balanced cross-section of the anticline and propose a kinematic evolution pathway constrained by the mesoscopic deformation pattern. Longitudinal and transversal deformation structures developed before and/or in the very early stages of fold growth. During this stage, the Bangestan anticline grew as a set of unconnected décollement anticlines involving the Cambrian to Pliocenic sedimentary cover. In a later stage, inherited basement faults were reactivated with a right-lateral strike-slip component and the previously developed anticlines propagated laterally up to their complete linkage and thrust breakthrough. This produced the right-lateral strike-slip reactivation of longitudinal joints and the development of N–S- and E–W-striking extensional structures, which were also frequently reworked as strike-slip faults.

On Non-Ideal Simple Portal Frame Structural Model: Experimental Results under a Non-Ideal Excitation

2004 ◽  
Vol 1-2 ◽  
pp. 51-58 ◽  
Author(s):  
José Manoel Balthazar ◽  
Reyolando Manoel Lopes Rabelo da Fonseca Brasil ◽  
F.J. Garzeri
Keyword(s):  
Structural Model ◽  
Excitation Frequency ◽  
High Amplitude ◽  
Sudden Increase ◽  
Motor Speed ◽  
Symmetrical Mode ◽  
Near Resonance ◽  
Portal Frame ◽  
Non Linear ◽  
Limited Power

We present measurements of the non-linear oscillations of a portal frame foundation for a non-ideal motor. We consider a three-time redundant structure with two columns, clamped in their bases and a horizontal beam. An electrical unbalanced motor is mounted at mid span of the beam. Two non-linear phenomena are studied: a) mode saturation and energy transfer between modes; b)interaction between high amplitude motions of the structure and the rotation regime of a real limited power motor. The dynamic characteristics of the structure were chosen to have one-to-two internal resonance between the anti-symmetrical mode (sway motions) and the first symmetrical mode natural frequencies. As the excitation frequency reaches near resonance conditions with the 2nd natural frequency, the amplitude of this mode grows up to a certain level and then it saturates. The surplus energy pumped into the system is transferred to the sway mode, which experiences a sudden increase in its amplitude. Energy is transformed from low amplitude high frequency motion into high amplitude low frequency motion. Such a transformation is potentially dangerous. We consider the fact that real motors, such as the one used in this study, have limited power output. In this case, this energy source is said to be non-ideal, in contrast to the ideal source whose amplitude and frequency are independent of the motion of the structure. Our experimental research detected the Sommerfeld Effect: as the motor accelerates to reach near resonant conditions, a considerable part of its output energy is consumed to generate large amplitude motions of the structure and not to increase its own angular speed. For certain parameters of the system, the motor can get stuck at resonance not having enough power to reach higher rotation regimes. If some more power is available, jump phenomena may occur from near resonance to considerably higher motor speed regimes, no stable motions being possible between these two.

Jurassic extension and Cenozoic inversion tectonics in the Asturian Basin, NW Iberian Peninsula: 3D structural model and kinematic evolution

2016 ◽  
Vol 90 ◽  
pp. 157-176 ◽  
Author(s):  
Hodei Uzkeda ◽  
Mayte Bulnes ◽  
Josep Poblet ◽  
José Carlos García-Ramos ◽  
Laura Piñuela
Keyword(s):  
Iberian Peninsula ◽  
Structural Model ◽  
Inversion Tectonics ◽  
Kinematic Evolution

Failure Modes of Perforated Material Under Finite Deformation

2008 ◽  
Vol 130 (4) ◽  
Author(s):  
Xinjian Duan ◽  
Arnaud Weck ◽  
David S. Wilkinson ◽  
Don R. Metzger
Keyword(s):  
Failure Modes ◽  
Structural Model ◽  
Cell Model ◽  
Local Deformation ◽  
Fracture Pattern ◽  
Plastic Strain Rate ◽  
Small Scale ◽  
Engineering Strain ◽  
Failure Path ◽  
Local Cell

Local deformation due to the interaction of small scale features such as voids or hard particles is expected to have a significant influence on the failure mode of a material. To this end, the fracture pattern of a perforated aluminum sheet is studied experimentally and numerically using finite element models on two different length scales: a full-scale structural model and a local cell model based on large deformation theory. Through the appropriate application of boundary conditions, the more efficient local cell model is shown to produce almost the same results as the full structural model. It is also found that the failure path is significantly affected by the loading conditions (uniaxial versus biaxial) and the hole distribution pattern. By plotting the instantaneous contours of the plastic strain rate, the fracture path can clearly be distinguished by the time that the overall engineering strain reaches approximately 3%. This model developed here has great potential to assess the integrity of high pressure components such as tubesheet.

Sign in / Sign up

Export Citation Format

Share Document