A Terrestrial Laser Scanner, Digital Photogrammetry, Hyperspectral Mapping and GPR Assisted Reservoir Analog Study
The study of outcrops is a viable tool in facies architecture and reservoir characterization studies. High resolution geometric surveys, including terrestrial laser scanning (TLS), allow 3-D photorealistic outcrop models to be captured and interpreted using robust analysis and visualization environment. A Riegl VZ-400 TLS was used to scan vertical cliffs of incised valleys within the Turonian Ferron Notom Delta in South-Central Utah. A total of 22 scans from different positions were merged with high accuracy (average RMS 0.003 m) by using numerous retro-reflective targets. High precision differential GPS solutions have been used to rotate and translate the survey frame coordinates to global coordinates, allowing the digitized geologic surfaces to be used in a GIS environment. Nearly five thousand digital images have been captured with the use of a tilting and rotating stage (GigaPanTM). A super-telephoto lens with focal length up to 500 mm allowed identification of small features, such as mud drapes, that are as small as a few millimeters in thickness. These high resolution digital images and the TLS data have been fused to create a 3-D virtual outcrop model. An approximately 600 m strip of river cut cliff faces have been modeled. The outcrop is composed of a series of laterally and vertically accreting tidally influenced channels that are exposed in a series of strike and dip aligned sections. Geologically important surfaces, such as sequence boundaries, maximum flooding surfaces and structural elements were mapped accurately in 3-D space on the model. Ongoing investigation is focused on a data fusion of the geometrically accurate 3-D photorealistic outcrop model with the hyperspectral imaging technology and ground penetrating radar (GPR) data. This type of data fusion will output a “true” 3-D reservoir model, and help address two issues of concern: (1) accurate 3-D geometry and heterogeneity of the facies architectural elements, and (2) porosity and permeability of reservoir facies. Resolving these types of unknowns is paramount to the oil and gas industry in developing accurate fluid flow simulations which, in turn, yield to enhanced recoveries from similarly deposited incised valley type reservoirs such as the one that occur within heavy oil deposits of the Cretaceous McMurray Formation in Northeastern Alberta.
AAPG Datapages/Search and Discovery Article #90189 © 2014 AAPG Annual Convention and Exhibition, Houston, Texas, USA, April 6–9, 2014