Armita Davarpanah - Academia.edu (original) (raw)

Papers by Armita Davarpanah

This dissertation analyzes the spatial distribution and kinematics of the Late Cenozoic Basin and... more This dissertation analyzes the spatial distribution and kinematics of the Late Cenozoic Basin and Range (BR) and cross normal fault (CF) systems and their related graben basins around the Snake River Plain (SRP), and investigates the spatio-temporal patterns of lavas that were erupted by the migrating Yellowstone hotspot along the SRP, applying a diverse set of GIS-based spatial statistical techniques. The spatial distribution patterns of the normal fault systems, revealed by the Ripley's K-function, display clustered patterns that correlate with a high linear density, maximum azimuthal variation, and high box-counting fractal dimensions of the fault traces. The extension direction for normal faulting is determined along the major axis of the fractal dimension anisotropy ellipse measured by the modified Cantor dust method and the minor axis of the autocorrelation anisotropy ellipse measured by Ordinary Kriging, and across the linear directional mean (LDM) of the fault traces. Tr...

Earth Science Informatics

We model the intermittent, non-linear interactions and feedback loops of the complex rare earth e... more We model the intermittent, non-linear interactions and feedback loops of the complex rare earth elements (REE) mineral system applying the self-organized criticality concept. Our semantic knowledge model (REE_MinSys ontology) represents dynamic primary and secondary processes that occur over a wide range of spatial and temporal scales and produce the emergent REE deposits and their geometry, tonnage, and grade. These include the scale-invariant, out-ofequilibrium geodynamic and magmatic processes that lead to the formation of orthomagmatic (carbonatite, alkaline igneous rocks) and syn-and post-magmatic hydrothermal REE deposits. The ontology also represents the redistribution of the REE from these primary ores by metamorphic fluids and/or post-depositional surface and supergene processes in sedimentary basins, fluvial channels, coast areas, and/or regolith around or above them. The ontology applies concepts of the complex systems theory to represent the spatial and spatio-temporal elements of the REE mineral system such as source, driver, threshold barriers, trigger, avalanche, conduit, relaxation, critical point attractor, and self-organization for the alkaline igneous, Iron oxide (subcategory of IOCG), hydrothermal, marine placers, alluvial placers (including paleo-placers), phosphorite, laterite, and ion-adsorption clays REE deposits. The ontology is instantiated with diverse data drawn from globally-distributed types of well-studied small to giant REE deposits to build the REE_MinSys knowledge base. Users can query the data in the knowledge base to extract explicit and inferred facts in each type of REE deposit, for example by asking: "Which rare earth elements are in REE phosphate deposits?"; "Which rare earth elements are largely explored in REE placer deposits?" Data from the knowledge base will be divided into training and testing sets after they are preprocessed and trends and data patterns are identified through data analytical procedures. The training and test datasets will be used to build models applying machine learning algorithms to predict potential REE deposits of different kinds in unexposed or covered areas.

Computers & Geosciences, 2018

We have developed the first iteration of the Plastic Rock Deformation (PRD) ontology by modeling ... more We have developed the first iteration of the Plastic Rock Deformation (PRD) ontology by modeling the semantics of a selected set of deformational processes and mechanisms that produce, reconfigure, displace, and/or consume the material components of inhomogeneous polycrystalline rocks. The PRD knowledge model also classifies and formalizes the properties (relations) that hold between instances of the dynamic physical and chemical processes and the rock components, the complex physio-chemical, mathematical, and informational concepts of the plastic rock deformation system, the measured or calculated laboratory testing conditions, experimental procedures and protocols, the state and system variables, and the empirical flow laws that define the interrelationships among the variables. The ontology reuses classes and properties from several existing ontologies that are built for physics, chemistry, biology, and mathematics. With its flexible design, the PRD ontology is well positioned to incrementally develop into a model that more fully represents the knowledge of plastic deformation of polycrystalline rocks in the future. The domain ontology will be used to consistently annotate varied data and information related to the microstructures and the physical and chemical processes that produce them at different spatial and temporal scales in the laboratory and in the solid Earth. The PRDKB knowledge base, when built based on the ontology, will help the community of experimental structural geologists and metamorphic petrologists to coherently and uniformly distribute, discover, access, share, and use their data through automated reasoning and integration and query of heterogeneous experimental deformation data that originate from autonomous rock testing laboratories.

Environmental Engineering Science, 2019

The FEWsOnt ontology models major structural and dynamic concepts of the food-energy-water (FEW) ... more The FEWsOnt ontology models major structural and dynamic concepts of the food-energy-water (FEW) systems from the complex system perspective by defining the emergent, nonlinear, and scale-invariant state transitions and behaviors of the network elements that result from natural and planned processes. The model represents the semantics of concepts such as security, footprint, challenge, risk, impact, and uncertainty in relation to governance and assessment of the level of sustainability of the FEW systems in varied domains of usage. The ontology will allow stakeholders working with the FEW systems' data to draw new inferences using semantic facts and discover insights and relationships among the systems' elements to make improved assessment and decisions toward sustainable growth. The knowledge-based model will lead users to optimize the tradeoffs and identify and prevent adverse changes to the FEW systems in relation to the interacting natural and social systems. The annotated terminology and formalized interactions in the ontology will facilitate the integration of the diverse FEW data types, improve communication among researchers, and help to reduce environmental stresses.

Earth Science Informatics, 2017

The sequence of eruption, spatial pattern, and spatiotemporal relationships among the Neogene-Qua... more The sequence of eruption, spatial pattern, and spatiotemporal relationships among the Neogene-Quaternary rhyolitic and basaltic lava along the Snake River Plain (SRP) in Idaho are analyzed applying the spatial methods of global and local Moran's I, standard deviational ellipse, and Ripley's K-function. The results of the analyses by the Moran's I and Kfunction methods indicate a higher spatial autocorrelation, hence clustering, of rhyolitic lava compared to the more dispersed basaltic lava in each center of eruption along the SRP. The clustered nature of rhyolitic lava around each caldera either reflects the original spread and large thickness of the rhyolitic lava, or the absence of younger cover strata or lava like the distribution of rhyolite in the present caldera at the Yellowstone National Park. The standard deviational ellipses (SDEs) of the lavas indicate that younger basaltic lava that erupted from newer calderas overlapped older rhyolitic and basaltic lava as the position of the Yellowstone hotspot progressively migrated to the northeast along the SRP. The less eccentric SDEs of rhyolitic lava in each caldera probably reflect the original caldera-scale spread of viscous felsic lava, compared to the more eccentric and larger SDEs of basaltic lava which represent basalt's wider and more directed spread due to its higher fluidity and ability to flow longer distances along the trend of the SRP. The alignment of the long axes of the lava SDEs with the trend of the Eastern SRP and the trend of systematic spatial overlap of older lava by successively younger basaltic lava corroborate the previously reported migration of the centers of eruption along the ESRP as the Yellowstone hotspot migrated to the northeast.

Geochemical composition and texture of the Middle and Late Eocene volcanic, volcaniclastic, and v... more Geochemical composition and texture of the Middle and Late Eocene volcanic, volcaniclastic, and volcanic- sedimentary rocks in the Bijgerd-Kuh-e Kharchin area, northwest of Saveh, provide significant geochemical and geological clues for the tectonic and magmatic evolution of the Uromieh-Dokhtar volcanic-plutonic zone of Iran. The Middle Eocene volcanic rocks have an intermediate composition and include green tuff and tuffaceous sandstone with intercalated sandstone, sandy tuff, and shale. The shale has lenses of nummulite- bearing limestone with a Middle Eocene detrital age. The time between the Middle and Late Eocene volcanic activities in this area is marked by the presence of andesite and rhyolitic tuff. The Late Eocene succession is distinguished by the presence of four alternating levels (horizons) of intermediate lava and ignimbrite which we designate as Eig. The ignimbrites of the Eig sequence have a rhyolitic composition and include ignimbrite- breccia, ignimbrite-tuff, and ...

Two slivers of Eocene volcanic rocks, separated by Pliocene-Quaternary conglomerate, are exposed,... more Two slivers of Eocene volcanic rocks, separated by Pliocene-Quaternary conglomerate, are exposed, northwest of the city of Saveh, along the Tertiary Uromieh-Dokhtar magmatic zone. The area north of Alishar, between 49o, 53'E and 50o,00'E longitudes and 35o, 17' N and 35o, 20' N latitudes, is located in the northern sliver. The oldest rocks north of Alishar have a Middle Eocene age, and are exposed in the core of an anticline which is faulted in its southern limb. These rocks are crystal and lithic tuff, and covered by rhyolitic ignimbrite. They are disconformably overlain by conglomerate, sandstone, marl, lenses of nummulite- bearing limestone, and green tuff. Fossils in the limestone give a Middle Eocene age. Bimodal, Late Eocene volcaniclastic and volcanic rocks cover these rocks. Evidence for acidic and intermediate volcanic activities is apparent at two levels. The early products of the explosive Late Eocene volcanic/volcaniclastic activity in this area were daci...

The region in northeastern Iran, bordered by the Miami fault and the Doruneh fault, mainly expose... more The region in northeastern Iran, bordered by the Miami fault and the Doruneh fault, mainly exposes the Eocene volcanic and Tertiary sedimentary rocks and sporadic outcrops of pre- Jurassic metamorphic rocks such as gneiss and mica-schist. We have divided the volcanic and volcanic-sedimentary rocks into six main units: E1 through the youngest E6. North of Abbas Abad, the Lower Eocene is conglomerate, sandstone, and red shale with lenses of nummulite-bearing limestone at the base, and dacitic lava (E1) at the top. The nummulites give an Early Eocene age for the limestone lenses. The E2 unit includes vesicular basalt, intercalated, intraformational conglomerate, and lenses of nummulite-bearing limestone. E3 is volcanic- sedimentary, and is made of green tuff, tuffite, shale, and nummulite bearing limestone. E4 includes basalt and vesicular trachy-basalt, and E5 is mostly sedimentary, made of tan marl, sandstone, shale, and lenses of Middle Eocene nummulite-bearing limestone. The E6 uni...

The mid-Tertiary Basin-and-Range extensional tectonic event developed most of the normal faults t... more The mid-Tertiary Basin-and-Range extensional tectonic event developed most of the normal faults that bound the ranges in the northern Rocky Mountains within Montana, Wyoming, and Idaho. The interaction of the thermally induced stress field of the Yellowstone hot spot with the existing Basin-and-Range fault blocks, during the last 15 my, has produced a new, spatially and temporally variable system of normal faults in these areas. The orientation and spatial distribution of the trace of these hot-spot induced normal faults, relative to earlier Basin-and-Range faults, have significant implications for the effect of the temporally varying and spatially propagating thermal dome on the growth of new hot spot related normal faults and reactivation of existing Basin-and-Range faults. Digitally enhanced LANDSAT 7 Enhanced Thematic Mapper Plus (ETM+) and Landsat 4 and 5 Thematic Mapper (TM) bands, with spatial resolution of 30 m, combined with analytical GIS and geological techniques helped i...

Tectonophysics, 2013

ABSTRACT The Basin and Range fault blocks, which were formed by an extensional event around 17 Ma... more ABSTRACT The Basin and Range fault blocks, which were formed by an extensional event around 17 Ma, have continuously been deforming by younger, diachronous system of cross normal faults in southwest Montana and southeastern Idaho since 16.6 Ma. Reactivation of these two mid-Tertiary-Quaternary systems of normal faults, and two older, approximately N-S and E-W sets of regional normal faults, has evolved into a seismically active block faulted terrain. For both fault systems, high fractal dimensions occur in areas characterized by a large number of fault traces, high fault trace linear density, and maximum fault trace azimuthal variation. The major axis of the anisotropy ellipse of the fractal dimensions for each set of the two normal fault systems is sub-perpendicular to the linear directional mean of the faults, and gives an estimate for the direction of extension.

This dissertation analyzes the spatial distribution and kinematics of the Late Cenozoic Basin and... more This dissertation analyzes the spatial distribution and kinematics of the Late Cenozoic Basin and Range (BR) and cross normal fault (CF) systems and their related graben basins around the Snake River Plain (SRP), and investigates the spatio-temporal patterns of lavas that were erupted by the migrating Yellowstone hotspot along the SRP, applying a diverse set of GIS-based spatial statistical techniques. The spatial distribution patterns of the normal fault systems, revealed by the Ripley's K-function, display clustered patterns that correlate with a high linear density, maximum azimuthal variation, and high box-counting fractal dimensions of the fault traces. The extension direction for normal faulting is determined along the major axis of the fractal dimension anisotropy ellipse measured by the modified Cantor dust method and the minor axis of the autocorrelation anisotropy ellipse measured by Ordinary Kriging, and across the linear directional mean (LDM) of the fault traces. Tr...

Earth Science Informatics

We model the intermittent, non-linear interactions and feedback loops of the complex rare earth e... more We model the intermittent, non-linear interactions and feedback loops of the complex rare earth elements (REE) mineral system applying the self-organized criticality concept. Our semantic knowledge model (REE_MinSys ontology) represents dynamic primary and secondary processes that occur over a wide range of spatial and temporal scales and produce the emergent REE deposits and their geometry, tonnage, and grade. These include the scale-invariant, out-ofequilibrium geodynamic and magmatic processes that lead to the formation of orthomagmatic (carbonatite, alkaline igneous rocks) and syn-and post-magmatic hydrothermal REE deposits. The ontology also represents the redistribution of the REE from these primary ores by metamorphic fluids and/or post-depositional surface and supergene processes in sedimentary basins, fluvial channels, coast areas, and/or regolith around or above them. The ontology applies concepts of the complex systems theory to represent the spatial and spatio-temporal elements of the REE mineral system such as source, driver, threshold barriers, trigger, avalanche, conduit, relaxation, critical point attractor, and self-organization for the alkaline igneous, Iron oxide (subcategory of IOCG), hydrothermal, marine placers, alluvial placers (including paleo-placers), phosphorite, laterite, and ion-adsorption clays REE deposits. The ontology is instantiated with diverse data drawn from globally-distributed types of well-studied small to giant REE deposits to build the REE_MinSys knowledge base. Users can query the data in the knowledge base to extract explicit and inferred facts in each type of REE deposit, for example by asking: "Which rare earth elements are in REE phosphate deposits?"; "Which rare earth elements are largely explored in REE placer deposits?" Data from the knowledge base will be divided into training and testing sets after they are preprocessed and trends and data patterns are identified through data analytical procedures. The training and test datasets will be used to build models applying machine learning algorithms to predict potential REE deposits of different kinds in unexposed or covered areas.

Computers & Geosciences, 2018

We have developed the first iteration of the Plastic Rock Deformation (PRD) ontology by modeling ... more We have developed the first iteration of the Plastic Rock Deformation (PRD) ontology by modeling the semantics of a selected set of deformational processes and mechanisms that produce, reconfigure, displace, and/or consume the material components of inhomogeneous polycrystalline rocks. The PRD knowledge model also classifies and formalizes the properties (relations) that hold between instances of the dynamic physical and chemical processes and the rock components, the complex physio-chemical, mathematical, and informational concepts of the plastic rock deformation system, the measured or calculated laboratory testing conditions, experimental procedures and protocols, the state and system variables, and the empirical flow laws that define the interrelationships among the variables. The ontology reuses classes and properties from several existing ontologies that are built for physics, chemistry, biology, and mathematics. With its flexible design, the PRD ontology is well positioned to incrementally develop into a model that more fully represents the knowledge of plastic deformation of polycrystalline rocks in the future. The domain ontology will be used to consistently annotate varied data and information related to the microstructures and the physical and chemical processes that produce them at different spatial and temporal scales in the laboratory and in the solid Earth. The PRDKB knowledge base, when built based on the ontology, will help the community of experimental structural geologists and metamorphic petrologists to coherently and uniformly distribute, discover, access, share, and use their data through automated reasoning and integration and query of heterogeneous experimental deformation data that originate from autonomous rock testing laboratories.

Environmental Engineering Science, 2019

The FEWsOnt ontology models major structural and dynamic concepts of the food-energy-water (FEW) ... more The FEWsOnt ontology models major structural and dynamic concepts of the food-energy-water (FEW) systems from the complex system perspective by defining the emergent, nonlinear, and scale-invariant state transitions and behaviors of the network elements that result from natural and planned processes. The model represents the semantics of concepts such as security, footprint, challenge, risk, impact, and uncertainty in relation to governance and assessment of the level of sustainability of the FEW systems in varied domains of usage. The ontology will allow stakeholders working with the FEW systems' data to draw new inferences using semantic facts and discover insights and relationships among the systems' elements to make improved assessment and decisions toward sustainable growth. The knowledge-based model will lead users to optimize the tradeoffs and identify and prevent adverse changes to the FEW systems in relation to the interacting natural and social systems. The annotated terminology and formalized interactions in the ontology will facilitate the integration of the diverse FEW data types, improve communication among researchers, and help to reduce environmental stresses.

Earth Science Informatics, 2017

The sequence of eruption, spatial pattern, and spatiotemporal relationships among the Neogene-Qua... more The sequence of eruption, spatial pattern, and spatiotemporal relationships among the Neogene-Quaternary rhyolitic and basaltic lava along the Snake River Plain (SRP) in Idaho are analyzed applying the spatial methods of global and local Moran's I, standard deviational ellipse, and Ripley's K-function. The results of the analyses by the Moran's I and Kfunction methods indicate a higher spatial autocorrelation, hence clustering, of rhyolitic lava compared to the more dispersed basaltic lava in each center of eruption along the SRP. The clustered nature of rhyolitic lava around each caldera either reflects the original spread and large thickness of the rhyolitic lava, or the absence of younger cover strata or lava like the distribution of rhyolite in the present caldera at the Yellowstone National Park. The standard deviational ellipses (SDEs) of the lavas indicate that younger basaltic lava that erupted from newer calderas overlapped older rhyolitic and basaltic lava as the position of the Yellowstone hotspot progressively migrated to the northeast along the SRP. The less eccentric SDEs of rhyolitic lava in each caldera probably reflect the original caldera-scale spread of viscous felsic lava, compared to the more eccentric and larger SDEs of basaltic lava which represent basalt's wider and more directed spread due to its higher fluidity and ability to flow longer distances along the trend of the SRP. The alignment of the long axes of the lava SDEs with the trend of the Eastern SRP and the trend of systematic spatial overlap of older lava by successively younger basaltic lava corroborate the previously reported migration of the centers of eruption along the ESRP as the Yellowstone hotspot migrated to the northeast.

Geochemical composition and texture of the Middle and Late Eocene volcanic, volcaniclastic, and v... more Geochemical composition and texture of the Middle and Late Eocene volcanic, volcaniclastic, and volcanic- sedimentary rocks in the Bijgerd-Kuh-e Kharchin area, northwest of Saveh, provide significant geochemical and geological clues for the tectonic and magmatic evolution of the Uromieh-Dokhtar volcanic-plutonic zone of Iran. The Middle Eocene volcanic rocks have an intermediate composition and include green tuff and tuffaceous sandstone with intercalated sandstone, sandy tuff, and shale. The shale has lenses of nummulite- bearing limestone with a Middle Eocene detrital age. The time between the Middle and Late Eocene volcanic activities in this area is marked by the presence of andesite and rhyolitic tuff. The Late Eocene succession is distinguished by the presence of four alternating levels (horizons) of intermediate lava and ignimbrite which we designate as Eig. The ignimbrites of the Eig sequence have a rhyolitic composition and include ignimbrite- breccia, ignimbrite-tuff, and ...

Two slivers of Eocene volcanic rocks, separated by Pliocene-Quaternary conglomerate, are exposed,... more Two slivers of Eocene volcanic rocks, separated by Pliocene-Quaternary conglomerate, are exposed, northwest of the city of Saveh, along the Tertiary Uromieh-Dokhtar magmatic zone. The area north of Alishar, between 49o, 53'E and 50o,00'E longitudes and 35o, 17' N and 35o, 20' N latitudes, is located in the northern sliver. The oldest rocks north of Alishar have a Middle Eocene age, and are exposed in the core of an anticline which is faulted in its southern limb. These rocks are crystal and lithic tuff, and covered by rhyolitic ignimbrite. They are disconformably overlain by conglomerate, sandstone, marl, lenses of nummulite- bearing limestone, and green tuff. Fossils in the limestone give a Middle Eocene age. Bimodal, Late Eocene volcaniclastic and volcanic rocks cover these rocks. Evidence for acidic and intermediate volcanic activities is apparent at two levels. The early products of the explosive Late Eocene volcanic/volcaniclastic activity in this area were daci...

The region in northeastern Iran, bordered by the Miami fault and the Doruneh fault, mainly expose... more The region in northeastern Iran, bordered by the Miami fault and the Doruneh fault, mainly exposes the Eocene volcanic and Tertiary sedimentary rocks and sporadic outcrops of pre- Jurassic metamorphic rocks such as gneiss and mica-schist. We have divided the volcanic and volcanic-sedimentary rocks into six main units: E1 through the youngest E6. North of Abbas Abad, the Lower Eocene is conglomerate, sandstone, and red shale with lenses of nummulite-bearing limestone at the base, and dacitic lava (E1) at the top. The nummulites give an Early Eocene age for the limestone lenses. The E2 unit includes vesicular basalt, intercalated, intraformational conglomerate, and lenses of nummulite-bearing limestone. E3 is volcanic- sedimentary, and is made of green tuff, tuffite, shale, and nummulite bearing limestone. E4 includes basalt and vesicular trachy-basalt, and E5 is mostly sedimentary, made of tan marl, sandstone, shale, and lenses of Middle Eocene nummulite-bearing limestone. The E6 uni...

The mid-Tertiary Basin-and-Range extensional tectonic event developed most of the normal faults t... more The mid-Tertiary Basin-and-Range extensional tectonic event developed most of the normal faults that bound the ranges in the northern Rocky Mountains within Montana, Wyoming, and Idaho. The interaction of the thermally induced stress field of the Yellowstone hot spot with the existing Basin-and-Range fault blocks, during the last 15 my, has produced a new, spatially and temporally variable system of normal faults in these areas. The orientation and spatial distribution of the trace of these hot-spot induced normal faults, relative to earlier Basin-and-Range faults, have significant implications for the effect of the temporally varying and spatially propagating thermal dome on the growth of new hot spot related normal faults and reactivation of existing Basin-and-Range faults. Digitally enhanced LANDSAT 7 Enhanced Thematic Mapper Plus (ETM+) and Landsat 4 and 5 Thematic Mapper (TM) bands, with spatial resolution of 30 m, combined with analytical GIS and geological techniques helped i...

Tectonophysics, 2013

ABSTRACT The Basin and Range fault blocks, which were formed by an extensional event around 17 Ma... more ABSTRACT The Basin and Range fault blocks, which were formed by an extensional event around 17 Ma, have continuously been deforming by younger, diachronous system of cross normal faults in southwest Montana and southeastern Idaho since 16.6 Ma. Reactivation of these two mid-Tertiary-Quaternary systems of normal faults, and two older, approximately N-S and E-W sets of regional normal faults, has evolved into a seismically active block faulted terrain. For both fault systems, high fractal dimensions occur in areas characterized by a large number of fault traces, high fault trace linear density, and maximum fault trace azimuthal variation. The major axis of the anisotropy ellipse of the fractal dimensions for each set of the two normal fault systems is sub-perpendicular to the linear directional mean of the faults, and gives an estimate for the direction of extension.