© 2017 by Luleå University of Technology

The Geological Survey of Denmark and Greenland

The Geological Survey of Denmark and Greenland is equipped with a computer-based photogrammetric tool to do accurate mapping from aerial and oblique photos. The digital photogrammetric workstation is a 3D-stereoplotter with two LCD polarized monitors set one above the other with an angle of 110° separated by a half-mirror. The polarized screens display a left-eye image and a right-eye image, which together represent stereo pair images overlapping each other by at least 60 %. The half-mirror is a beam-splitter that transmits 50 % of the light and reflects the others 50 %. The depth perception is allowed by wearing 3D polarized glasses with left- and right-eye lenses polarized in different directions while a 3D-mouse allows full navigation in the 3D environment. The workstations are equipped with StereoBlend and SocetSet softwares and geological features observed in 3D, such as intra-formational beddings, formation boundaries along with faults and fractures are digitized as 3D polylines, later imported into other software for visualization and 3D modelling.

In the last five years, GEUS has been in the development of a storage facility for digital 3D geological models. The concept is to make a procedure that can manage and store 3D geological model data in an independent uniform format. Thereby capable of handling interchangeable formats between different independent 3D model software programs through a spatial database.

The idea is to maximize the potential of the data and take advantage of the high detailed geological data models combined with the simpler models in a unified environment and thereby achieve a maximum potential use of existing basic data. Furthermore, there is a need to manage and assure the quality of data at a consistently high level, through a structured infrastructure in the form of a dynamic database. Providing an optimal maintenance and future security of data as well as a better exchange between the various modeling tools gives a higher quality assurance, flexibility and at least future-proof usability of the data.

The primary objective is to compile a database tool that can handle the exchange of regional reference subsurface layers for an upcoming National 3D Geological Model. The geology between the surfaces are then to be defined through standardized lithology, as well as folds, faults and other complex geological structures.

The aim is to go for a non-licensed database for the potential use of an open source database like the PostgreSQL/PostGIS, for better exchange of the technology and cooperation through organizations. The concept is to implement the first prototype into GEUS existing database infrastructure in the end of 2017.

3D/VR hardware:

- Photogrammetry Lab

- 3D-projector and silver screen for wide audience presentations

- Oracle Spatial 11g and PostgreSQL database

Developed and used 3D/4D modelling software:

- Gocad

- Move3D

- SocetSet

- StereoBlend

- FME (Feature Manipulation Engine)

- MeshLab

- Petrel

- WebGL

Recent/ongoing projects:

- Geological Mapping in Greenland

- Analogue projects for oil companies

- Structural mapping for mining exploration companies

- 3D database development

- Development of a prototype for 3D visualization on the internet

The 3D workstation at GEUS.

Visual presentation of a 3D geological outcrop surface model in a prototype viewer using WebGL.

Contact:

Dr. Pierapolo Guarnieri

The Geological Survey of Denmark and Greenland

Denmark

pgua[AT]geus.dk