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Exploring 3-D Data Sets With GIS. Damion Knudsen. Background. North Dakota State University Environmental and Conservation Sciences Program and Dakota Technologies, Inc. in Fargo, North Dakota .
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Exploring 3-D Data Sets With GIS Damion Knudsen
Background North Dakota State University Environmental and Conservation Sciences Program and Dakota Technologies, Inc. in Fargo, North Dakota People I would like to thank for data sets and guidance in the preparation of this presentation are: Dr. Bernhardt Saini-Eidukat, Dr. Frank Casey, and Dr. Peter Oduor of NDSU Randy St. Germain, President of Dakota Technologies, Inc. of Fargo, North Dakota Dr. Rinita Dalan of Moorhead State Univerisity Bruce Juenker of the NDIC Oil and Gas Division Kris Roberts of the NDDH Ground Water Division BS in Geology Minor in Chemistry Pursuing MS Advisor Dr. Bernhardt Saini-Eidukat, Chairman of the Geosciences Department at NDSU
Classic 2-D GIS 2-D GIS gives the following ways to represent 3-D structures Filled and Line Contours Shaded Relief Maps Tins Raster Grids Cross Sections Google Earth has revolutionized the visualization of the 3-D Earth and has become popular among casual computer users ArcGlobe and ArcScene have much more capabilities than Google Earth. Google recently bought SketchUp from @Last Software. It will be interesting to see how that works out. I will give examples of other ways that GIS can be used to represent the 3-D environment
North Dakota Geology In this first model I will show an example map of the subsurface geology of North Dakota produced from borehole data readily available from the NDIC Oil and Gas Division.
North Dakota Geology This solid model was formed from approximately 14,000 wells across North Dakota 100x vert. exag.
North Dakota Geology Examples: Madison Group Red River Formation View Facing South East Solid regions below the surface represent major oil producing formations 100x vert. exag.
North Dakota Geology Here is another view with cross sections and North Dakota counties floating over head 100x vert. exag.
View Looking East • View Looking South North Dakota Geology Cross Section reveals Nesson anticline • Structure suggests mid Jurassic down warp 100x vert. exag.
North Dakota Geology The Foreman Butte oil field in McKenzie County of North Dakota produces largely from the Madison Group 100x vert. exag.
North Dakota Geology Oil Well boreholes are represented by blue points 100x vert. exag.
Oil Producing Field in McKenzie County Oil sat. in % A major producing region of the Madison Group in the Foreman Butte oil field is considered the Ratcliffe Interval These cross sections represents oil saturation in percent scaling from 0% to 97% versus water 200x vert. exag.
Oil Producing Field in McKenzie County • Resistivity cross sections 200x vert. exag. Porosity and resistivity 3-D grids are used to calculate oil saturation using the Archie equation Porosity cross sections 1- Sw • Oil Saturation cross sections
Oil Producing Field in McKenzie County These are Iso-surfaces representing the intersection of 8 % porosity with 45% oil saturation An iso-surface is considered to be a 3-D contour 200x vert. exag.
Oil Producing Field in McKenzie County Iso-surfaces can be compressed to 2-D and overlaid on a plan map to delineate the areas of potential oil production
Groundwater Non-Aqueous Phase Liquid (NAPL) Contaminant Characterization Using Laser Induced Fluorescence (LIF) and 3-D GIS in Morton County, ND Boreholes representing LIF response through a free phase diesel fuel source term in Morton County % RE • Cross section of source term plume drawn through boreholes 50x vert. exag.
Groundwater Non-Aqueous Phase Liquid (NAPL) Contaminant Characterization Using Laser Induced Fluorescence (LIF) and 3-D GIS in Morton County, ND % RE Iso-surfaces of free phase diesel within the water table LIF acquires data at approximately 1 inch intervals. Dakota Technologies, Inc. uses LIF to collect data as shown above 50x vert. exag.
NDSU Oakes, ND Nitrate leaching study area This study area was used to research the leaching of nitrates through groundwater • Solid model with aerial photo draped on surface 50x vert. exag.
NDSU Oakes, ND Nitrate leaching study area • Soil pH iso-surface pH Sand and sandy loams • Clays and clayey loams 50x vert. exag.
NDSU Oakes, ND Nitrate leaching study area • Soil pH iso-surface pH Sand and sandy loam Cross sections • Clays and clayey loam in voxel (3-D pixel) format • Groundwater NO3 -concentration 50x vert. exag.
NDSU Oakes, ND Nitrate leaching study area Solid hydraulic conductivity model of area. Units in in/hr 50x vert. exag. • Model mesh could be used in ModFlow??
Archaeological Site in Cass County, North Dakota 15x vert. exag. Area thought to contain remains of ancient activity including firepits • Use of Magnetic Susceptibility, LIDAR, and 6 inch resolution images in model
Archaeological Site in Cass County, North Dakota Fire pits should leave remains of reduced iron in the form of magnetite or similar minerals. Paleosols and the A horizon should have the least amount of these minerals shown in pink 15x vert. exag.
Archaeological Site in Cass County, North Dakota Cross sections Paleosols Possible fire pits in red. 15x vert. exag.
Archaeological Site in Cass County, North Dakota Iso-surfaces of possible fire pits in blue. 15x vert. exag.
Areas of Improvement • ArcScene has not changed much in 5 years • Would like to see 3-D editor in ArcScene and ArcGlobe • Ability to publish maps similar to ArcGlobe and ArcMap. • 3-D measurements in ArcScene • Automatic 3-D legend and graticule options • 3-D selections between a volume or separate raster grids or tins • 3-D interpolations and iso-surface generation in 3D Analyst • Volumetric measurements of 3-D iso-surface models
Observations • Higher resolution subsurface data will always provide the most accurate representation of a subsurface distribution. Forms of high resolution data available today are: • Laser Induced Fluorescence (LIF) UVOST or TarGOST • Cone Penetrometer Test (CPT) This can be used in conjunction with a LIF system • Magnetic Susceptibility • Wireline and Measuring/Logging While Drilling (M/L WD) tools used in the petroleum industry and for geophysical testing • When collecting subsurface data it is always best to acquire highly accurate coordinates and elevations for your data if you plan to use it for 3-D mapping.
Future Applications • 3-D data could be supplied from an IMS server to be viewed through the internet similar to Google Earth • Practical in a few years when Vista forces people to use 3-D acceleration and internet speeds increase