Requirements for Topology in 3D GIS

Topology and its various benefits are well understood within the context of 2D Geographical Information Systems. However, requirements in three-dimensional (3D) applications have yet to be defined, with factors such as lack of users' familiarity with the potential of such systems impeding this process. In this paper, we identify and review a number of requirements for topology in 3D applications. The review utilises existing topological frameworks and data models as a starting point. Three key areas were studied for the purposes of requirements identification, namely existing 2D topological systems, requirements for visualisation in 3D and requirements for 3D analysis supported by topology. This was followed by analysis of application areas such as earth sciences and urban modelling which are traditionally associated with GIS, as well as others including medical, biological and chemical science. Requirements for topological functionality in 3D were then grouped and categorised. The paper concludes by suggesting that these requirements can be used as a basis for the implementation of topology in 3D. It is the aim of this review to serve as a focus for further discussion and identification of additional applications that would benefit from 3D topology. © 2006 The Authors. Journal compilation © 2006 Blackwell Publishing Ltd

A 3d geoscience information system framework

Two-dimensional geographical information systems are extensively used in the geosciences to create and analyse maps. However, these systems are unable to represent the Earth's subsurface in three spatial dimensions. The objective of this thesis is to overcome this deficiency, to provide a general framework for a 3d geoscience information system (GIS), and to contribute to the public discussion about the development of an infrastructure for geological observation data, geomodels, and geoservices. Following the objective, the requirements for a 3d GIS are analysed. According to the requirements, new geologically sensible query functionality for geometrical, topological and geological properties has been developed and the integration of 3d geological modeling and data management system components in a generic framework has been accomplished. The 3d geoscience information system framework presented here is characterized by the following features: - Storage of geological observation data and geomodels in a XML-database server. According to a new data model, geological observation data can be referenced by a set of geomodels. - Functionality for querying observation data and 3d geomodels based on their 3d geometrical, topological, material, and geological properties were developed and implemented as plug-in for a 3d geomodeling user application. - For database queries, the standard XML query language has been extended with 3d spatial operators. The spatial database query operations are computed using a XML application server which has been developed for this specific purpose. This technology allows sophisticated 3d spatial and geological database queries. Using the developed methods, queries can be answered like: "Select all sandstone horizons which are intersected by the set of faults F". This request contains a topological and a geological material parameter. The combination of queries with other GIS methods, like visual and statistical analysis, allows geoscience investigations in a novel 3d GIS environment. More generally, a 3d GIS enables geologists to read and understand a 3d digital geomodel analogously as they read a conventional 2d geological map

Innovative Approaches to 3D GIS Modeling for Volumetric and Geoprocessing Applications in Subsurface Infrastructures in a Virtual Immersive Environment

As subsurface features remain largely ‘out of sight, out of mind’, this has led to challenges when dealing with underground space and infrastructures and especially so for those working in GIS. Since subsurface infrastructure plays a major role in supporting the needs of modern society, groups such as city planners and utility companies and decision makers are looking for an ‘holistic’ approach where the sustainable use of underground space is as important as above ground space. For such planning and management, it is crucial to examine subsurface data in a form that is amenable to 3D mapping and that can be used for increasingly sophisticated 3D modeling. The subsurface referred to in this study focuses particularly on examples of both shallow and deep underground infrastructures. In the case of shallow underground infrastructures mostly two-dimensional maps are used in the management and planning of these features. Depth is a very critical component of underground infrastructures that is difficult to represent in a 2D map and for this reason these are best studied in three-dimensional space. In this research, the capability of 3D GIS technology and immersive geography are explored for the storage, management, analysis, and visualization of shallow and deep subsurface features

BeSpaceD: Towards a Tool Framework and Methodology for the Specification and Verification of Spatial Behavior of Distributed Software Component Systems

In this report, we present work towards a framework for modeling and checking behavior of spatially distributed component systems. Design goals of our framework are the ability to model spatial behavior in a component oriented, simple and intuitive way, the possibility to automatically analyse and verify systems and integration possibilities with other modeling and verification tools. We present examples and the verification steps necessary to prove properties such as range coverage or the absence of collisions between components and technical details

Three-dimensional anatomical atlas of the human body

A thesis submitted in partial fulfillment of the requirements for the degree of Doctor in Information Management, specialization in Geographic Information SystemsAnatomical atlases allow mapping the anatomical structures of the human body. Early versions of these systems consisted of analogic representations with informative text and labelled images of the human body. With the advent of computer systems, digital versions emerged and the third dimension was introduced. Consequently, these systems increased their efficiency, allowing more realistic visualizations with improved interactivity. The development of anatomical atlases in geographic information systems (GIS) environments allows the development of platforms with a high degree of interactivity and with tools to explore and analyze the human body. In this thesis, a prototype for the human body representation is developed. The system includes a 3D GIS topological model, a graphical user interface and functions to explore and analyze the interior and the surface of the anatomical structures of the human body. The GIS approach relies essentially on the topological characteristics of the model and on the kind of available functions, which include measurement, identification, selection and analysis. With the incorporation of these functions, the final system has the ability to replicate the kind of information provided by the conventional anatomical atlases and also provides a higher level of functionality, since some of the atlases limitations are precisely features offered by GIS, namely, interactive capabilities, multilayer management, measurement tools, edition mode, allowing the expansion of the information contained in the system, and spatial analyzes

Combinatorial models for topology-based geometric modeling

Many combinatorial (topological) models have been proposed in geometric modeling, computational geometry, image processing or analysis, for representing subdivided geometric objects, i.e. partitionned into cells of different dimensions: vertices, edges, faces, volumes, etc. We can distinguish among models according to the type of cells (regular or not regular ones), the type of assembly ("manifold" or "non manifold"), the type of representation (incidence graphs or ordered models), etc

Geologic controls on fluid flow and seismic imaging of faults in carbonate rocks : Insights from quantitative outcrop analysis and reflection seismic modeling

Utforsking av undergrunnen har historisk sett hovudsakleg vore drive av økonomiske insentiv gjennom leiting etter hydrokarbon og andre geologiske ressursar. I nyare tid, derimot, har geologiens rolle i det grøne skiftet fått aukande fokus. Undergrunnen er svært viktig for blant anna CO2- og hydrogenlagring, grunnvassressursar og geotermisk energi, og avgjerande for alle disse bruksområda er strukturar som forkastingar og sprekkenettverk, og deira kontroll på væskestraum i undergrunnen. Hovudfokuset i denne avhandlinga er å forbetre forståinga av undergrunnen gjennom to overordna tema; (i) kontrollen forkastings- og sprekkenettverk har på væskestraum og reaksjonar mellom væsker og bergartar, og (ii) seismisk avbilding av slike forkastingar og deira væske-bergart reaksjonsprodukt i undergrunnen. Sjølv om det er generell einigheit i at geologiske strukturer utøver sterk kontroll på væskestraum, har få forsøkt å kvantifisere dette forholdet. I samsvar med tema (i) ovanfor byrjar denne avhandlinga difor med å kvantifisere og visualisere forholdet mellom væskestraum og strukturell kompleksitet (Artikkel 1). Ved hjelp av sementerte haugar med lav porøsitet som bevis for paleo-væskestraum, nyttast topologi for å karakterisere og visualisere strukturell kompleksitet i lokaliserte område, og kvantitativt dokumentere deira korrelasjon med områder for lokalisert paleo-væskestraum. Artikkel 2 gir ei oversikt over geologiske kontrollar på væskestraum i sedimentære bergartar, basert på ein kombinasjon av litteraturanalyse og studie av eksempel frå felt der jernoksidutfelling blir brukt som bevis for paleo-væskestraum. Artikkelen dokumenterer eit vidt spenn av kontrollar på væskestraum og inkluderer alt frå enkle geologiske heterogeniteter til meir komplekse nettverk av strukturar, og dokumenterer og kvantifiserer topologien til både sprekkenettverk og hybridnettverk beståande av ein kombinasjon av sprekker og sedimentære avsetningsstrukturar som fungerer som leiarar for væskestraum. Eit viktig verktøy for kartlegging av slike væskeleiande strukturar i undergrunnen er seismiske refleksjonsdata. I tråd med Tema (ii), undersøkjer Artikkel 3 effekten av småskala forkastingar (nær eller under seismisk oppløysing) på seismiske bilde ved hjelp av seismisk modellering. Hovudmålet i denne artikkelen er å dokumentere effekten som forkastingar under- eller på grensa til seismisk oppløysing kan ha på seismiske data. For eksempel illustrerer artikkelen korleis subtile forandringar i ein refleksjon kan vere resultat av små forkastingar i undergrunnen, noko som er viktig ny innsikt og som mogleg kan bidra til å forbetre tolking av strukturar i seismikk. I tillegg til avbilding av forkastingar i seg sjølv, er også produkta av væske-bergart interaksjon av interesse, og det er derfor viktig å også forstå deira seismiske signatur. Ved hjelp av seismisk modellering av forkastingskontrollerte dolomittar i ei kalksteinsdominert sone i Suezbukta, blir seismisk avbilding av både massive og stratigrafisk kontrollerte dolomittkroppar undersøkt med varierande geologiske og geofysiske parametrar i Artikkel 4. Resultata i denne artikkelen gir ny innsikt i korleis forkastingskontrollerte hydrotermale dolomittkroppar blir avbilda i seismiske data; artikkelen dokumenterer at dei generelle trendane og nærværet av dolomitt i undergrunnen er mogleg å slutte frå seismiske data, men identifisering av individuelle, stratigrafisk kontrollerte dolomittkroppar er ikkje stadfesta mogleg. Funna frå denne avhandlinga fremjar den grunnleggande forståinga av sentrale geologiske kontrollar på væskestraum i undergrunnen, og avbilding av potensielt strøymingskontrollerande forkastingar og deira bergreaktive produkt i refleksjonsseismiske data. Den nye innsikta presentert i avhandlinga har eit breitt spekter av implikasjonar og nytteområde, for eksempel for lokalisering av økonomisk betydelege førekomstar av nyttige mineral, i risikovurdering for CO2- og hydrogenlagring, grunnvasshandtering, lokalisering av forureining, og meir.Exploration of the sub-surface has historically largely been driven by economic incentives through potential hydrocarbon recovery, but more recently the role of subsurface geology in the green shift has gained more focus. The subsurface are highly important for CO2- and hydrogen storage, freshwater resources, and geothermal energy to name a few, and crucial for all these are structures such as faults and their conjugate damage zones, veins, joints, and deformation bands, as well as the depositional architecture of the host rock. This thesis aim to improve our understanding of the sub-surface through two overarching themes, (i) fault and fracture networks and their controls on fluid flow and fluid-rock interaction, and (ii) the seismic imaging of such faults and their fluid-rock reactive products in the subsurface. Despite the consensus that structures exert strong control on fluid flow, few have attempted to quantify this relationship. In accordance with theme (i) above, this thesis therefore starts by quantifying and visualizing the relationship between fluid flow and structural complexity; using low-porosity cemented mounds as a record of paleo-fluid flow and topological characterization, zones of past fluid flow and areas of structural complexity are correlated and documented. Further, an overview of controls on fluid flow is given through literature review and documentation of outcrops using iron oxide precipitates as proxy for paleo-fluid flow; the fluid flow controls are ranging from simple geological heterogeneities to more complex networks of structures, and through topological characterization, the connectivity of fracture networks and hybrid networks are documented. The structures controlling flow can be found at all scales, but as the most commonly used tool for subsurface investigation is seismic imaging many of these will fall below seismic resolution. Following theme (ii), we investigate the effect of sub-seismic faults on seismic imaging using synthetic seismic from outcrop analogues and prove that under the right conditions, faults with throw as low as 5 m still produce distortion of reflections. But not only fault and fractures but also the products of fluid-rock interaction are of interest to explore in the subsurface, and hence it is important to understand their seismic signature. Using seismic modelling of fault-controlled dolomites in a limestone-dominated succession in the Golf of Suez it is found that the presence of both stratabound and massive dolomite bodies can be inferred, although only the massive dolomite can be distinguished individually. The findings form this thesis have implications for the fundamental understanding of how fluids are controlled in the subsurface, and present examples of how these controls might be imaged in reflection seismic data. This is in turn critical for a variety of processes and areas such as locating economically significant ore deposits, hydrocarbon seal risk assessment, prediction of earthquakes, groundwater management, and more. Due to the vast number of processes that are controlled by sub-surface fluid flow it is of both environmental, societal, and economic interest to be able to predict and understand fluid flow pathways, how they interact to form networks, and how they and their fluid-rock interactive products might be portrayed in reflection seismic data.Doktorgradsavhandlin