Using GIS to Display Well Bore Stratigraphy and Analytical Data in 3D

April 9th, 2009

Graham S. Hayes, Ph.D., GISP

Wendel DuchschererArchitects & Engineers

Presentation Outline

GIS OverviewData Formats and Sources3D Data ManipulationHamden, CT Case StudyDiscussion

What is a GIS?Geographic Information System

Management tool for maps & databasesTwo types of information: spatial data (location) and attribute data (descriptive)Capture, store, retrieve, analyze and display dataInformation stored in thematic layers

123

123Map Graphics(spatial data)

Tabular Tabular DatabasesDatabases(attributes)(attributes)

GIS Models Real World Objects as Graphic Features

Points

Lines

Polygons

Text

Presentation Outline

GIS OverviewData Formats and Sources3D Data ManipulationHamden, CT Case StudyDiscussion

Data Formats and Sources

AttributesLocations, elevations, depth, sample results, etc.Excel, Access, GINT, text files, etc.

Map FeaturesVector

Points, Lines & PolygonsAttribute tables, CAD, GPS

RasterDigital Elevation Models (DEMs)Aerial Photos & Scanned USGS maps

Triangular Irregular Networks (TINs)

Data Formats and Sources (continued)

Keys for Successful AttributesGather or compute X,Y and Z values if possible. Be consistent in recording elevations (e.g. ground, riser, casing, etc.)Store text in text fields, numbers in numeric fields. Don’t store depth ranges in mixed units in a single field.

depth

0-6”

2-4

12-18

start

0.0

2.0

12.0

end

0.5

4.0

14.0

thickness

0.5

2.0

6.0

Data Formats and Sources (continued)

Keys for Successful Attributes (continued)

Use standard naming conventions for wells-IDs, sample-IDs, etc. (e.g. MW-105a; MW 105 a; MW105A)Be consistent in applying the standards. Relational databases live and die based on common IDs between tables.

Well-id

mw105mw106

mw107

start

0.0

2.0

12.0

end

0.5

4.0

14.0

thickness

0.5

2.0

6.0

Well-id

mw-105

mw-105

mw 105? ? ?

? ? ?elev

501.5539.2

495.7

Data Formats and Sources (continued)

Keys for Successful Map FeaturesGather available basemap data from USGS and state GIS data clearing houses (e.g. DEMs, DOQQs, USGS quad sheets, basemap shapefiles, etc.)Use real world coordinates (state plane feet NAD83, UTM, etc.)

CAD data should be in model space (not paper space or mixed model and paper space)Elevation data in CAD should be stored as block attributes not just as textAvoid inset maps in CAD if porting data to GIS

Presentation Outline

GIS OverviewData Formats and Sources3D Data ManipulationHamden, CT Case StudyDiscussion

3D Data Manipulation

Data CreationCreate 3D surfaces from XYZ values

Raster GRIDs from point dataTINs from point, line and polygon data

Derive contours from 3D surfacesCompute areas and volumes from 3D surfacesConvert 2D vector data to 3D dataPerform visualization studies

3D Data Manipulation (continued)

Data VisualizationDrape 2D or image data over raster or TIN surfaces Represent sample locations in 3DExtrude or offset 2D data by constant or attribute (e.g. building height, bore hole depth, thickness, etc.)

Symbolize attribute values by color and sizeSet transparency and illumination Create “fly through” animations

Presentation Outline

GIS OverviewData Formats and Sources3D Data ManipulationHamden, CT Case StudyDiscussion

Hamden, Connecticut

Since the early 1900’s, residents and factories in Hamden, CT dumped refuse into a low lying wetland.In 1932, Olin Corporation purchased Winchester Firearms and continued the practice of dumping slag and ash from their factory in the municipal dump.As recent as 1972, homes, parks, a school and sports fields have been constructed on top of the now filled wetland.

Hamden, Connecticut (continued)

An environmental study determined that hazardous materials were present and remediation was necessary.Hired as a technical consultant by the law firm representing Olin Corporation to perform a forensic review of the landfill to:

determine the source and volume of the waste materialestablish the timing and aerial extent of the landfillvisualize the relationships between the waste material and the hazardous chemical components.

1998 aerial photo showing the outline of the fill area.

1949

19491943

1934 1965

1970 1975 1980

Summary of Filling at Hamden Middle School

Historic photo (1980) draped over digital elevation model

3D view of the original wetland elevation surface prior to filling

3D view of the current elevation surface after filling

3D view of the study area.

3D view of the fill area and the contours of total fill thickness

Concentration of Arsenic (mg/kg) above the RDEC of 10 mg/kgLarger symbols indicate higher concentrations.

Concentration of Lead (mg/kg) above the RDEC of 400 mg/kg.Larger symbols indicate higher concentrations.

Concentration of Benzo(a)pyrene (ug/kg) above the RDEC of 1,000 ug/kg. Larger symbols indicate higher concentrations.

Aerial distribution and total thickness of all fill classes greater than 1.5 ft thick (4 foot contour interval).

Aerial distribution and total thickness of refuse fill greater than 1.5 ft thick (4 foot contour interval).

Aerial distribution and total thickness of waste fill greater than 1.5 ft thick (4 foot contour interval).

Aerial distribution and total thickness of clean fill greater than 1.5 ft thick (4 foot contour interval).

Tan = clean fillGrey = waste fillGreen = refuse fill

Landfill Stratigraphy & Geochemistry Landfill Stratigraphy & Geochemistry

Red = Arsenic

Green = LeadLight blue =

Benzo(a)pyrene

Presentation Outline

GIS OverviewData Formats and Sources3D Data ManipulationHamden, CT Case StudyDiscussion