GeoIllustrator is a joint inter-department research project between Department of Informatics and Department of GeoSciences at UiB, Christian Michelsen Research AS and the Norwegian oil and gas company Statoil. This web page contains information related to the PhD research done at the Department of Informatics at the University of Bergen.
As the name suggests the GeoIllustrator project deals with illustrative geology. During the project we will develop new and better ways to digitally model and illustrate geological data and geological concepts. By using state of the art computer graphics and interaction hardware, GeoIllustrator will contribute novel ideas to the science field of visualization and computer graphics. Application for these new ideas within geology will be many, for instance for expert-to-expert communication, for expert-to-layman communication, for interactive educational tools and for day-to-day modelling and visualisation within the geology domain.
This is a 3 year PhD project and it started on January 1st 2010.

Research topics

  • Illustrative visualisation of geology models
  • Illustrative visualisation of ground-truth-data
  • Sketch-based modelling and visual hypothesis exploration

Research Partners

  • Christian Michelsen Research
  • Statoil
  • Department of Earth Science, University of Bergen




    [PDF] [Bibtex]
    @ARTICLE {Natali14Rapid,
    author = "Mattia Natali and Julius Parulek and Daniel Patel",
    title = "Rapid Modelling of Interactive Geological Illustrations with Faults and Compaction",
    journal = "Proceedings of Spring Conference on Computer Graphics (SCCG)",
    year = "2014",
    abstract = "In this paper, we propose new methods for building geological illustrations and animations. We focus on allowing geologists to create their subsurface models by means of sketches, to quickly communicate concepts and ideas rather than detailed information. The result of our sketch-based modelling approach is a layer-cake volume representing geological phenomena, where each layer is rock material which has accumulated due to a user-defined depositional event. Internal geological structures can be inspected by different visualization techniques that we employ. Faulting and compaction of rock layers are important processes in geology. They can be modelled and visualized with our technique. Our representation supports non-planar faults that a user may define by means of sketches. Real-time illustrative animations are achieved by our GPU accelerated approach.",
    pdf = "pdfs/Natali14Rapid.pdf",
    images = "images/Natali2014Rapid0.png, images/Natali2014Rapid1.png",
    thumbnails = "images/Natali2014Rapid0.png, images/Natali2014Rapid1.png",
    url = "",
    project = "geoillustrator"
    [DOI] [VID] [Bibtex]
    @ARTICLE {Natali14Sketch,
    author = "Mattia Natali and Tore Grane Klausen and Daniel Patel",
    title = "Sketch-Based Modelling and Visualization of Geological Deposition",
    journal = "Computers \& Geosciences",
    year = "2014",
    volume = "67C",
    pages = "40--48",
    abstract = "We propose a method for sketching and visualizing geological models by sequentially defining stratigraphic layers, where each layer represents a unique erosion or deposition event. Evolution of rivers and deltas is important for geologists when interpreting the stratigraphy of the subsurface, in particular for hydrocarbon exploration. We illustratively visualize mountains, basins, lakes, rivers and deltas, and how they change the morphology of a terrain during their evolution. We present a compact representation of the model and a novel rendering algorithm that allows us to obtain an interactive and illustrative layer-cake visualization. A user study has been performed to evaluate our method.",
    vid = "vids/Natali2014Sketch.mp4",
    images = "images/Natali2014Sketch0.png, images/Natali2014Sketch1.png",
    thumbnails = "images/Natali2014Sketch0.png, images/Natali2014Sketch1.png",
    doi = "10.1016/j.cageo.2014.02.010",
    url = "",
    project = "geoillustrator"
    [PDF] [Bibtex]
    @PHDTHESIS {natali14thesis,
    author = "Mattia Natali",
    title = "Sketch-based Modelling and Conceptual Visualization of Geomorphological Processes for Interactive Scientific Communication",
    school = "Department of Informatics, University of Bergen, Norway",
    year = "2014",
    month = "September",
    abstract = "Throughout this dissertation, solutions for rapid digitalization of ideas will be defined.More precisely, the focus is on interactive scientific sketching and communication of geology, where theresult is a digital illustrative 3D model. Results are achieved through a sketch-based modellingapproach which gives the user a more natural and intuitive modelling process, hence leading to aquicker definition of a geological illustration. To be able to quickly externalize and communicate onesideas as a digital 3D model, can be of importance. For instance, students may profit from explanationssupported by interactive illustrations. Exchange of information and hypotheses between domain expertsis also a targeted situation in our work. Furthermore, illustrative models are frequently employed in business, when decisional meetings take place for convincing the management that a project is worth to be funded. An advantage of digital models is that they can be saved and they are easy to distribute. In contrast to 2D images or paper sketches, one can interact with digital 3D models, and they can be transferred on portable devices for easy access (for instance during geological field studies). Another advantage, compared to standard geological illustrations, is that if a model has been created with internal structures, it can be arbitrarily cut and inspected. Different solutions for different aspects of subsurface geology are presented in this dissertation. To express folding and faulting processes, a first modelling approach based on cross-sectional sketches is introduced. User defined textures can be associated to each layer, and can then be deformed with sketch strokes, for communicating layer properties such as rock type and grain size. A following contribution includes a simple and compact representation to model and visualize 3D stratigraphic models. With this representation, erosion and deposition offluvial systems are easy to specify and display. Ancient river channels and other geological features, which are present in the subsurface, can be accessed by means of a volumetric representation. Geological models are obtained and visualized by sequentially defining stratigraphic layers, where each layer represents a unique erosion or deposition event. Evolution of rivers and deltas is important for geologists when interpreting the stratigraphy of the subsurface, in particular because it changes the landscape morphology and because river deposits are potential hydrocarbon reservoirs. Time plays a fundamental role in geological processes. Animations are well suited for communicating temporal change and a contribution in this direction is also given. With the techniques developed in this thesis, it becomes possible to produce a range of geological scenarios. The focus is on enabling geologists tocreate their subsurface models by means of sketches, to quickly communicate concepts and ideasrather than detailed information. Although the proposed techniques are simple to use and requirelittle design effort, complex models can be realized. ",
    pdf = "pdfs/natali14thesis.pdf",
    images = "images/Natali2014Rapid0.png, images/Natali2014Sketch0.png,",
    thumbnails = "images/Natali2014Rapid0.png, images/Natali2014Sketch0.png,",
    isbn = "?? ",
    url = "",
    project = "geoillustrator"


    [DOI] [Bibtex]
    @ARTICLE {Lidal13Geological,
    author = "Endre M. Lidal and Mattia Natali and Daniel Patel and Helwig Hauser and Ivan Viola",
    title = "Geological storytelling",
    journal = "Computers \& Graphics",
    year = "2013",
    volume = "37",
    number = "5",
    pages = "445--459 ",
    abstract = "Developing structural geological models from exploratory subsea imaging is difficult and an ill-posed process. The structural geological processes that take place in the subsurface are both complex and time-dependent. We present Geological Storytelling, a novel graphical system for performing rapid and expressive geomodeling. Geologists can convey geological stories that externalize both their model and the reasoning process behind it through our simple, yet expressive sketch-based, flip-over canvases. This rapid modeling interface makes it easy to construct a large variety of geological stories, and our story tree concept facilitates easy management and the exploration of these alternatives. The stories are then animated and the geologists can examine and compare them to identify the most plausible models. Finally, the geological stories can be presented as illustrative animations of automatically synthesized 3D models, which efficiently communicate the complex geological evolution to non-experts and decision makers. Geological storytelling provides a complete pipeline from the ideas and knowledge in the mind of the geologist, through externalized artifacts specialized for discussion and knowledge dissemination among peer-experts, to automatically rendered illustrative 3D animations for communication to lay audience. We have developed geological storytelling in collaboration with domain experts that work with the modeling challenges on a daily basis. For evaluation, we have developed a geological storytelling prototype and presented it to experts and academics from the geosciences. In their feedback, they acknowledge that the rapid and expressive sketching of stories can make them explore more alternatives and that the 3D illustrative animations assist in communicating their models.",
    images = "images/Lidal13Geological01.jpg, images/Lidal13Geological02.png",
    thumbnails = "images/Lidal13Geological01.jpg, images/Lidal13Geological02.png",
    issn = "0097-8493",
    doi = "",
    url = "",
    keywords = "Sketch-based modeling; Externalization of mental processes; Storytelling; 3D model synthesis; Animation; Alternatives exploration; Geology; Structural geological models",
    project = "geoillustrator"
    [PDF] [DOI] [Bibtex]
    @INPROCEEDINGS {Natali13Modeling,
    author = "Mattia Natali and Endre M. Lidal and Julius Parulek and Ivan Viola and Daniel Patel",
    title = "Modeling Terrains and Subsurface Geology",
    booktitle = "EuroGraphics 2013 State of the Art Reports (STARs)",
    year = "2013",
    pages = "155--173",
    abstract = "The process of creating terrain and landscape models is important in a variety of computer graphics and visualization applications, from films and computer games, via flight simulators and landscape planning, to scientific visualization and subsurface modelling. Interestingly, the modelling techniques used in this large range of application areas have started to meet in the last years. In this state-of-the-art report, we present two taxonomies of different modelling methods. Firstly we present a data oriented taxonomy, where we divide modelling into three different scenarios: the data-free, the sparse-data and the dense-data scenario. Then we present a workflow oriented taxonomy, where we divide modelling into the separate stages necessary for creating a geological model. We start the report by showing that the new trends in geological modelling are approaching the modelling methods that have been developed in computer graphics. We then give an introduction to the process of geological modelling followed by our two taxonomies with descriptions and comparisons of selected methods. Finally we discuss the challenges and trends in geological modelling.",
    pdf = "pdfs/Natali13Modeling.pdf",
    images = "images/Natali13Modeling.png",
    thumbnails = "images/Natali13Modeling.png",
    proceedings = "EuroGraphics 2013 State of the Art Reports (STARs)",
    url = "",
    doi = "10.2312/conf/EG2013/stars/155-173",
    location = "Girona, Spain",
    project = "geoillustrator"
    [PDF] [DOI] [YT] [Bibtex]
    @ARTICLE {Patel-2013-ICS,
    author = "Daniel Patel and Veronika \v{S}olt{\'e}szov{\'a} and Jan Martin Nordbotten and Stefan Bruckner",
    title = "Instant Convolution Shadows for Volumetric Detail Mapping",
    journal = "ACM Transactions on Graphics",
    year = "2013",
    volume = "32",
    number = "5",
    pages = "154:1--154:18",
    month = "sep",
    abstract = "In this article, we present a method for rendering dynamic scenes  featuring translucent procedural volumetric detail with all-frequency  soft shadows being cast from objects residing inside the view frustum.  Our approach is based on an approximation of physically correct shadows  from distant Gaussian area light sources positioned behind the view  plane, using iterative convolution. We present a theoretical and  empirical analysis of this model and propose an efficient class of  convolution kernels which provide high quality at interactive frame  rates. Our GPU-based implementation supports arbitrary volumetric  detail maps, requires no precomputation, and therefore allows for  real-time modi?cation of all rendering parameters.",
    pdf = "pdfs/Patel-2013-ICS.pdf",
    images = "images/Patel-2013-ICS.jpg",
    thumbnails = "images/Patel-2013-ICS.png",
    youtube = ",",
    doi = "10.1145/2492684",
    keywords = "shadows, volumetric effects, procedural texturing, filtering",
    project = "geoillustrator",
    url = ""
    [PDF] [Bibtex]
    @PHDTHESIS {lidal13thesis,
    author = "Endre M. Lidal",
    title = "Sketch-based Storytelling for Cognitive Problem Solving",
    school = "Department of Informatics, University of Bergen, Norway",
    year = "2013",
    month = "June",
    abstract = "Problem solving is an important part of all engineering and scienti�c activities. It is present, for instance, when experts want to develop more fuel- ef�cient cars or when they are searching for oil and gas in the subsurface. Many alternatives have to be examined and evaluated before the optimal solution is found. Solving such problems is not only performed inside the mind of the scientist, but it is also an interaction between mind and scribbles, sketches, or visualizations on papers, on blackboards, and on computers. For problem solving in expert teams, this externalization through sketches and visualizations also plays an important communicative role. This dissertation presents research for assisting the problem- solving process on the computer, through novel technological advances in the �elds of illustrative visualization and sketch-based modeling. Speci�cally, it targets problems that are related to evolutionary processes. Firstly, inspired by storytelling, the domain experts can express their ideas for solution as stories. These stories are based on sketches that the experts draw, utilizing a novel temporal-sketching interface inspired by a flip-over canvas metaphor. Further, the dissertation describes a set of sketching proxy geometries, such as the box-proxy geometry, that the experts can take advantage of when drawing three-dimensional (3D) sketches. These proxy geometries support the task of mapping a two-dimensional input (2D), e.g., a mouse or a digitizer tablet, to a 3D sketch. Solving dif�cult problems require that many different solutions are evaluated to identify the most optimal one. This dissertation introduces the story-tree, a tree-graph data structure and visualization, which manages and provides access to an ensemble of alternative stories. The story- tree also provides an interface where the stories can be evaluated and compared. This playback of the stories is done through automatic animations of the 2D sketches. The third challenge addressed in this dissertation is to communicate the optimal solution to decision-makers and laymen. By combining the animated 2D story sketches with illustrative visualization techniques it is possible to automatically synthesize and animate 3D models. These animations can be combined with new cutaway visualization techniques to reveal features hidden inside such 3D models. All of these contributions have been investigated in the context of the problemsolving tasks relevant to the early phase of petroleum exploration. This phase is characterized by having very little ground-through data available. Thus, a large solution space needs to be explored. Even so, the geologists need to produce models that can predict if petroleum is present. In addition to working with few data, the geologists also work under heavy time constraints because of the competition between the oil companies exploring the same area. The contributions from this dissertation have created enthusiasm among the domain experts and already, a new research initiative has materialized from the work described in this dissertation. Based on the feedback from the domain experts, we can conclude that the contributions presented in this dissertation form a valuable step towards better tools for problem solving, involving the computer, for the domain investigated here. ",
    pdf = "pdfs/lidal13thesis.pdf",
    images = "images/lidal13thesis.png",
    thumbnails = "images/lidal13thesis.png",
    isbn = "978-82-308-2330-9",
    project = "geoillustrator"
    [PDF] [Bibtex]
    @INPROCEEDINGS {Lidal13Rapid,
    author = "Endre Lidal and Daniel Patel and Morten Bendiksen and Tor Langeland and Ivan Viola",
    title = "Rapid Sketch-based 3D Modeling of Geology",
    booktitle = "Proceedings of EnvirVis Short Papers 2013",
    year = "2013",
    abstract = "We present and compare two different approaches for performing rapid 3D geological modeling. The ad-hoc approach is based on a composition of many specialized modeling functions, while the generic approach provides one powerful, generic modeling function. Our experiences after developing these two approaches are that the solution space of 3D geological modeling is more extensive than we initially expected and most likely larger than for other modeling domains such as architecture. Further, more research is needed to investigate whether it is possible to �nd one well de�ned toolset of sketching metaphors that is able to cover all of geological modeling.",
    pdf = "pdfs/Lidal13Rapid.pdf",
    images = "images/Lidal13Rapid01.png",
    thumbnails = "images/Lidal13Rapid01_thumb.png",
    project = "geoillustrator"


    [PDF] [DOI] [Bibtex]
    @INPROCEEDINGS {Lidal12Geological,
    author = "Endre M. Lidal and Helwig Hauser and Ivan Viola ",
    title = "Geological Storytelling - Graphically Exploring and Communicating Geological Sketches",
    booktitle = "Proceedings of Sketch-Based Interfaces and Modeling (SBIM 2012)",
    year = "2012",
    pages = "11--20",
    abstract = "Developing structural geological models from exploratory subsea imaging is difficult and an ill-posed process. Therefore, in practice several experts generate a larger number of geological interpretations. This leads to the situation that a number of geological sketches are prepared and examined for the next steps in the oil and gas exploration pipeline. In this paper, we present Geological Storytelling, a novel graphical approach for performing rapid and expressive geomodeling of a multitude of model variations. The solution builds on a flip-over metaphor for sketching the individual steps in a story that externalizes the mental steps the modeler performs when developing the model. The stories, through the discrete story steps, are then visualized in a Story Tree for easy access and management. This tree also provides the interface for individual story playback and examination, or comparative visualization of several stories. With our approach, the experts can rapidly sketch geological stories that both visualize the proposed model of today's geology and visualize how the expert derived this model. Presenting the model as a visual story helps the peers to evaluate the geological soundness of the model. We have developed geological storytelling in collaboration with domain experts that work with such challenges on a daily basis. Our focus of this work has been on models derived from single seismic slices. We have implemented a prototype of Geological Storytelling to demonstrate our concept and to get domain expert feedback.",
    pdf = "pdfs/Lidal12Geological.pdf",
    images = "images/Lidal12Geological01.png, images/Lidal12Geological02.png",
    thumbnails = "images/Lidal12Geological01_thumb.png, images/Lidal12Geological02_thumb.png",
    url = "",
    doi = "10.2312/SBM/SBM12/011-020",
    project = "geoillustrator"
    [DOI] [Bibtex]
    @INPROCEEDINGS {Natali12Rapid,
    author = "Mattia Natali and Ivan Viola and Daniel Patel",
    title = "Rapid Visualization of Geological Concepts",
    booktitle = "SIBGRAPI 2012 (XXV Conference on Graphics, Patterns and Images)",
    year = "2012",
    editor = "C. Freitas, L. Silva, R. Scopigno, and S. Sarkar",
    address = "Ouro Preto, MG, Brazil",
    month = "August",
    abstract = "We describe a sketch-based system for constructing an illustrative visualization of the subsurface. An intuitive and rapid modelling tool is defined, which takes as input user's strokes and creates a 3D layer-cake model of the earth. Our tool enables users to quickly express and communicate their ideas directly using a 3D model. For sketching, we have created geometric operators that capture the domain specific modelling requirements.We have devised sketching operators for expressing folding and faulting processes. This makes it possible to produce a large span of scenarios. Moreover, for communicating layer properties such as rock type and grain size, our system allows for associating user defined texture to each layer which can be deformed with a few sketch strokes.",
    images = "images/Natali12Rapid01.png, images/Natali12Rapid02.png",
    thumbnails = "images/Natali12Rapid01_thumb.png, images/Natali12Rapid02_thumb.png",
    url = "",
    doi = "10.1109/SIBGRAPI.2012.29",
    project = "geoillustrator"
    [PDF] [Bibtex]
    @INPROCEEDINGS {Lidal12Design,
    author = "Endre M. Lidal and Helwig Hauser and Ivan Viola",
    title = "Design Principles for Cutaway Visualization of Geological Models",
    booktitle = "Proceedings of Spring Conference on Computer Graphics (SCCG 2012)",
    year = "2012",
    pages = "53--60",
    month = "May",
    abstract = "In this paper, we present design principles for cutaway visualizations that emphasize shape and depth communication of the focus features and their relation to the context. First, to eliminate cutaway-flatness we argue that the cutaway axis should have an angular offset from the view direction. Second, we recommend creating a box-shaped cutaway. Such a simple cutaway shape allows for easier context extrapolation in the cutaway volume. Third, to improve the relationship between the focus features and the context, we propose to selectively align the cutaway shape to familiar structures in the context. Fourth, we emphasize that the illumination model should effectively communicate the shape and spatial ordering inside the cutaway, through shadowing as well as contouring and other stylized shading models. Finally, we recommend relaxing the view-dependency constraint of the cutaway to improve the depth perception through the motion parallax. We have identified these design principles while developing interactive cutaway visualizations of 3D geological models, inspired by geological illustrations and discussions with the domain illustrators and experts.",
    pdf = "pdfs/Lidal12Design.pdf",
    images = "images/Lidal12Design01.jpg, images/Lidal12Design02.jpg",
    thumbnails = "images/Lidal12Design01_thumb.jpg, images/Lidal12Design02_thumb.jpg",
    location = "Smolenice castle, Slovakia",
    project = "geoillustrator"


    [PDF] [DOI] [YT] [Bibtex]
    @INPROCEEDINGS {Patel-2010-SVV,
    author = "Daniel Patel and Stefan Bruckner and Ivan Viola and Meister Eduard Gr{\"o}ller",
    title = "Seismic Volume Visualization for Horizon Extraction",
    booktitle = "Proceedings of IEEE Pacific Visualization 2010",
    year = "2010",
    pages = "73--80",
    month = "mar",
    abstract = "Seismic horizons indicate change in rock properties and are central  in geoscience interpretation. Traditional interpretation systems  involve time consuming and repetitive manual volumetric seeding for  horizon growing. We present a novel system for rapidly interpreting  and visualizing seismic volumetric data. First we extract horizon  surface-parts by preprocessing the seismic data. Then during interaction  the user can assemble in realtime the horizon parts into horizons.  Traditional interpretation systems use gradient-based illumination  models in the rendering of the seismic volume and polygon rendering  of horizon surfaces. We employ realtime gradientfree forward-scattering  in the rendering of seismic volumes yielding results similar to high-quality  global illumination. We use an implicit surface representation of  horizons allowing for a seamless integration of horizon rendering  and volume rendering. We present a collection of novel techniques  constituting an interpretation and visualization system highly tailored  to seismic data interpretation.",
    pdf = "pdfs/Patel-2010-SVV.pdf",
    images = "images/Patel-2010-SVV.jpg",
    thumbnails = "images/Patel-2010-SVV.png",
    youtube = "",
    doi = "10.1109/PACIFICVIS.2010.5429605",
    keywords = "volume visualization, horizon extraction, seismic data",
    location = "Taipei, Taiwan",
    project = "geoillustrator,illvis",
    url = ""