Luisa Zuluaga | University of Bergen (original) (raw)
Papers by Luisa Zuluaga
AGU Fall Meeting Abstracts, Dec 1, 2019
AGU Fall Meeting Abstracts, Dec 1, 2020
Journal of Structural Geology, 2017
The way that faults interact with each other controls fault geometries, displacements and strains... more The way that faults interact with each other controls fault geometries, displacements and strains. Faults rarely occur individually but as sets or networks, with the arrangement of these faults producing a variety of different fault interactions. Fault interactions are characterised in terms of the following: 1) Geometry – the spatial arrangement of the faults. Interacting faults may or may not be geometrically linked (i.e. physically connected), when fault planes share an intersection line. 2) Kinematics – the displacement distributions of the interacting faults and whether the displacement directions are parallel, perpendicular or oblique to the intersection line. Interacting faults may or may not be kinematically linked, where the displacements, stresses and strains of one fault influences those of the other. 3) Displacement and strain in the interaction zone – whether the faults have the same or opposite displacement directions, and if extension or contraction dominates in the acute bisector between the faults. 4) Chronology – the relative ages of the faults. This characterisation scheme is used to suggest a classification for interacting faults. Different types of interaction are illustrated using metre-scale faults from the Mesozoic rocks of Somerset and examples from the literature
AGU Fall Meeting Abstracts, Dec 1, 2020
Journal of Structural Geology, 2015
Contractional deformation of highly porous sandstones is poorly explored, as compared to extensio... more Contractional deformation of highly porous sandstones is poorly explored, as compared to extensional deformation of such sedimentary rocks. In this work we explore the highly porous Aztec Sandstone in the footwall to the Muddy Mountain thrust in SE Nevada, which contains several types of deformation bands in the Buffington tectonic window: 1) Distributed centimeter-thick shear-enhanced compaction bands (SECBs) and 2) rare pure compaction bands (PCBs) in the most porous parts of the sandstone, cut by 3) thin cataclastic shear-dominated bands (CSBs) with local slip surfaces. Geometric and kinematic analysis of the SECBs, the PCBs and the majority of the CSBs shows that they formed during ~E-W (~N100E)
Journal of Structural Geology, 2014
The work presented in this thesis is part of the Contraction of Porous Sandstones project (COPS),... more The work presented in this thesis is part of the Contraction of Porous Sandstones project (COPS), conducted at Uni Research CIPR and the Department of Earth Science at the University of Bergen (UiB), Norway, in collaboration with the Laboratoire Géosciences at the Université Montpellier in France. The PhD scholarship was funded by Uni Research CIPR; travel grants from Statoil allowed international dissemination of research outcomes and discussions for progress. While carrying out the research for this thesis, the candidate has been enrolled in the doctoral training program at the Faculty of Mathematics and Natural Sciences at the
Geological Society, London, Special Publications, 2017
Abstract Little is known about the effect of thrusting on lithological and petrophysical properti... more Abstract Little is known about the effect of thrusting on lithological and petrophysical properties of reservoir sandstone. Here we use field observations, probe permeability measurements and thin-section analysis along ten transects from the Muddy Mountain thrust contact downwards into the underlying Jurassic Aztec Sandstone to evaluate the nature and extent of petrophysical and microstructural changes caused by the thrusting. The results reveal a decimetre- to metre-thick low-permeable (≤50 mD) and indurated (0–3% porosity) zone immediately beneath the thrust contact in which dominant microscale processes, in decreasing order of importance, are (1) cataclasis with local fault gouge formation; (2) pressure solution; and (3) very limited cementation. From this narrow zone the petrophysical and microstructural effect of the thrusting decreases gradually downwards into a friable, highly porous (c. 25%) and permeable (≤2 D) sandstone some 50–150 m below the thrust, in which strain is localized into deformation band populations. In general, the petrophysical properties of the sandstone as a result of overthrusting reveal little impact in overall primary reservoir quality below some tens of metres into the footwall, except for the relatively minor baffling effect of deformation bands.
Earth and Planetary Sciences are characterized by a lack of gender and ethnic diversity across jo... more Earth and Planetary Sciences are characterized by a lack of gender and ethnic diversity across job sectors, particularly in academia and industry. This imbalance is not representative of current demographic distributions, neither of the general population at large nor the people completing tertiary education in these fields. Gender and ethnic diversity is correlated with improved performance and productivity: In academia as better indicators of research quality and successful grant applications; in industry as higher long-term profitability and better public perception of their corporate values. Despite this, the change has been slow in persuading institutions and companies to create systemic changes to harness this potential.
Journal of Structural Geology
Increased interest in the two-and three-dimensional geometries and development of faults and othe... more Increased interest in the two-and three-dimensional geometries and development of faults and other types of fractures in rock has led to an increasingly bewildering terminology. Here we give definitions for the geometric, topological, kinematic and mechanical relationships between geological faults and other types of fractures, focussing on how they relate to form networks.
AAPG Bulletin, 2016
Porous siliciclastic reservoirs are known to contain structural heterogeneities such as deformati... more Porous siliciclastic reservoirs are known to contain structural heterogeneities such as deformation bands, which fall below current seismic resolution and which generally cannot be explicitly represented in reservoir models because of the prohibitively high computational cost. In this study, we built a reservoir model to evaluate fluid flow across a contractionally folded unit containing deformation bands (the Navajo Sandstone in the San Rafael Reef monocline, Utah). Using field data, geometric relationships, and auxiliary computational techniques, we upscale deformation bands to capture flow effects in the large-scale structure, running simulations with variable scenarios of permeability contrast between host rock and deformation bands. Our simulations show that pervasive deformation band arrays (such as the ones present in the monocline) have effects when the contrast of permeability between them and the host rock is of at least three orders of magnitude, delaying water breakthrough and enhancing sweep; in long-term production, this results in larger final produced volumes and higher total recovery. Because of the wide range of deformation band permeabilities used in this study, our findings can be of importance for the prediction of flow and optimization of production strategies in comparable traps and reservoirs. Additionally, auxiliary computational techniques and geometric relationships such as the ones presented in this study can significantly improve the incorporation of small-scale features with strong scale gap into conventional sized reservoirs.
Journal of Structural Geology, 2014
Journal of Structural Geology, 2015
Contractional deformation of highly porous sandstones is poorly explored, as compared to extensio... more Contractional deformation of highly porous sandstones is poorly explored, as compared to extensional deformation of such sedimentary rocks. In this work we explore the highly porous Aztec Sandstone in the footwall to the Muddy Mountain thrust in SE Nevada, which contains several types of deformation bands in the Buffington tectonic window: 1) Distributed centimeter-thick shear-enhanced compaction bands (SECBs) and 2) rare pure compaction bands (PCBs) in the most porous parts of the sandstone, cut by 3) thin cataclastic shear-dominated bands (CSBs) with local slip surfaces. Geometric and kinematic analysis of the SECBs, the PCBs and most of the CSBs shows that they formed during~EeW (~100) shortening, consistent with thrusting related to the Cretaceous to early Paleogene Sevier orogeny of the North American Cordilleran thrust system. Based on stress path modeling, we suggest that the compactional bands (PCBs and SECBs) formed during contraction at relatively shallow burial depths, before or at early stages of emplacement of the Muddy Mountains thrust sheet. The younger cataclastic shear bands (CSBs, category 3), also related to EeW Sevier thrusting, are thinner and show larger shear offsets and thus more intense cataclasis, consistent with the initiation of cataclastic shear bands in somewhat less porous materials. Observations made in this work support earlier suggestions that contraction lead to more distributed band populations than what is commonly found in the extensional regime, and that shearenhanced compaction bands are widespread only where porosity (and permeability) is high.
AGU Fall Meeting Abstracts, Dec 1, 2019
AGU Fall Meeting Abstracts, Dec 1, 2020
Journal of Structural Geology, 2017
The way that faults interact with each other controls fault geometries, displacements and strains... more The way that faults interact with each other controls fault geometries, displacements and strains. Faults rarely occur individually but as sets or networks, with the arrangement of these faults producing a variety of different fault interactions. Fault interactions are characterised in terms of the following: 1) Geometry – the spatial arrangement of the faults. Interacting faults may or may not be geometrically linked (i.e. physically connected), when fault planes share an intersection line. 2) Kinematics – the displacement distributions of the interacting faults and whether the displacement directions are parallel, perpendicular or oblique to the intersection line. Interacting faults may or may not be kinematically linked, where the displacements, stresses and strains of one fault influences those of the other. 3) Displacement and strain in the interaction zone – whether the faults have the same or opposite displacement directions, and if extension or contraction dominates in the acute bisector between the faults. 4) Chronology – the relative ages of the faults. This characterisation scheme is used to suggest a classification for interacting faults. Different types of interaction are illustrated using metre-scale faults from the Mesozoic rocks of Somerset and examples from the literature
AGU Fall Meeting Abstracts, Dec 1, 2020
Journal of Structural Geology, 2015
Contractional deformation of highly porous sandstones is poorly explored, as compared to extensio... more Contractional deformation of highly porous sandstones is poorly explored, as compared to extensional deformation of such sedimentary rocks. In this work we explore the highly porous Aztec Sandstone in the footwall to the Muddy Mountain thrust in SE Nevada, which contains several types of deformation bands in the Buffington tectonic window: 1) Distributed centimeter-thick shear-enhanced compaction bands (SECBs) and 2) rare pure compaction bands (PCBs) in the most porous parts of the sandstone, cut by 3) thin cataclastic shear-dominated bands (CSBs) with local slip surfaces. Geometric and kinematic analysis of the SECBs, the PCBs and the majority of the CSBs shows that they formed during ~E-W (~N100E)
Journal of Structural Geology, 2014
The work presented in this thesis is part of the Contraction of Porous Sandstones project (COPS),... more The work presented in this thesis is part of the Contraction of Porous Sandstones project (COPS), conducted at Uni Research CIPR and the Department of Earth Science at the University of Bergen (UiB), Norway, in collaboration with the Laboratoire Géosciences at the Université Montpellier in France. The PhD scholarship was funded by Uni Research CIPR; travel grants from Statoil allowed international dissemination of research outcomes and discussions for progress. While carrying out the research for this thesis, the candidate has been enrolled in the doctoral training program at the Faculty of Mathematics and Natural Sciences at the
Geological Society, London, Special Publications, 2017
Abstract Little is known about the effect of thrusting on lithological and petrophysical properti... more Abstract Little is known about the effect of thrusting on lithological and petrophysical properties of reservoir sandstone. Here we use field observations, probe permeability measurements and thin-section analysis along ten transects from the Muddy Mountain thrust contact downwards into the underlying Jurassic Aztec Sandstone to evaluate the nature and extent of petrophysical and microstructural changes caused by the thrusting. The results reveal a decimetre- to metre-thick low-permeable (≤50 mD) and indurated (0–3% porosity) zone immediately beneath the thrust contact in which dominant microscale processes, in decreasing order of importance, are (1) cataclasis with local fault gouge formation; (2) pressure solution; and (3) very limited cementation. From this narrow zone the petrophysical and microstructural effect of the thrusting decreases gradually downwards into a friable, highly porous (c. 25%) and permeable (≤2 D) sandstone some 50–150 m below the thrust, in which strain is localized into deformation band populations. In general, the petrophysical properties of the sandstone as a result of overthrusting reveal little impact in overall primary reservoir quality below some tens of metres into the footwall, except for the relatively minor baffling effect of deformation bands.
Earth and Planetary Sciences are characterized by a lack of gender and ethnic diversity across jo... more Earth and Planetary Sciences are characterized by a lack of gender and ethnic diversity across job sectors, particularly in academia and industry. This imbalance is not representative of current demographic distributions, neither of the general population at large nor the people completing tertiary education in these fields. Gender and ethnic diversity is correlated with improved performance and productivity: In academia as better indicators of research quality and successful grant applications; in industry as higher long-term profitability and better public perception of their corporate values. Despite this, the change has been slow in persuading institutions and companies to create systemic changes to harness this potential.
Journal of Structural Geology
Increased interest in the two-and three-dimensional geometries and development of faults and othe... more Increased interest in the two-and three-dimensional geometries and development of faults and other types of fractures in rock has led to an increasingly bewildering terminology. Here we give definitions for the geometric, topological, kinematic and mechanical relationships between geological faults and other types of fractures, focussing on how they relate to form networks.
AAPG Bulletin, 2016
Porous siliciclastic reservoirs are known to contain structural heterogeneities such as deformati... more Porous siliciclastic reservoirs are known to contain structural heterogeneities such as deformation bands, which fall below current seismic resolution and which generally cannot be explicitly represented in reservoir models because of the prohibitively high computational cost. In this study, we built a reservoir model to evaluate fluid flow across a contractionally folded unit containing deformation bands (the Navajo Sandstone in the San Rafael Reef monocline, Utah). Using field data, geometric relationships, and auxiliary computational techniques, we upscale deformation bands to capture flow effects in the large-scale structure, running simulations with variable scenarios of permeability contrast between host rock and deformation bands. Our simulations show that pervasive deformation band arrays (such as the ones present in the monocline) have effects when the contrast of permeability between them and the host rock is of at least three orders of magnitude, delaying water breakthrough and enhancing sweep; in long-term production, this results in larger final produced volumes and higher total recovery. Because of the wide range of deformation band permeabilities used in this study, our findings can be of importance for the prediction of flow and optimization of production strategies in comparable traps and reservoirs. Additionally, auxiliary computational techniques and geometric relationships such as the ones presented in this study can significantly improve the incorporation of small-scale features with strong scale gap into conventional sized reservoirs.
Journal of Structural Geology, 2014
Journal of Structural Geology, 2015
Contractional deformation of highly porous sandstones is poorly explored, as compared to extensio... more Contractional deformation of highly porous sandstones is poorly explored, as compared to extensional deformation of such sedimentary rocks. In this work we explore the highly porous Aztec Sandstone in the footwall to the Muddy Mountain thrust in SE Nevada, which contains several types of deformation bands in the Buffington tectonic window: 1) Distributed centimeter-thick shear-enhanced compaction bands (SECBs) and 2) rare pure compaction bands (PCBs) in the most porous parts of the sandstone, cut by 3) thin cataclastic shear-dominated bands (CSBs) with local slip surfaces. Geometric and kinematic analysis of the SECBs, the PCBs and most of the CSBs shows that they formed during~EeW (~100) shortening, consistent with thrusting related to the Cretaceous to early Paleogene Sevier orogeny of the North American Cordilleran thrust system. Based on stress path modeling, we suggest that the compactional bands (PCBs and SECBs) formed during contraction at relatively shallow burial depths, before or at early stages of emplacement of the Muddy Mountains thrust sheet. The younger cataclastic shear bands (CSBs, category 3), also related to EeW Sevier thrusting, are thinner and show larger shear offsets and thus more intense cataclasis, consistent with the initiation of cataclastic shear bands in somewhat less porous materials. Observations made in this work support earlier suggestions that contraction lead to more distributed band populations than what is commonly found in the extensional regime, and that shearenhanced compaction bands are widespread only where porosity (and permeability) is high.