Introduction
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description
Introduction. Mapping is the foundation of the geological sciences. Three basic elements in geologic map Location Lithologic information Spatial or geometrical relationships - PowerPoint PPT Presentation
Transcript of Introduction
Introduction• Mapping is the foundation of the geological
sciences.• Three basic elements in geologic map
– Location– Lithologic information– Spatial or geometrical relationships
• Providing the digital data sets representing the real earth so that a “virtual” earth can be simulated on the computer and then virtual model displayed and analyzed in “virtual reality” system.
CYBERMAPPING: Integration of GPS, Reflectorless Laser
Rangefinders and GIS
Technology
• GPS: global positioning to a centimeter.
• Lasers: relative positioning of decimeter to centimeter.
• GIS: mapping functionalities.
• Digital Cameras
• ??
GPS Techniques
Comparing accuracy, baseline, and time required for positions. SPS, PPS = autonomous position. OTF=on-the-fly kinematic post-processing. RTK=real time OTF kinematic..
Summary of the approximate accuracy of GPS positioning versus methods. (Modified from Featherstone, 1995)
RTK Base Station
Radio Transmitter GPS Base Antenna
RTK Rover Station
L a s e r b e a m
w ith 3 m i l l i ra d ia n d iv .
d if fu s e re f le c t io n
T a rg e t
L a s e r ra n g e-f in d e r
re c e iv e r a p e r tu re
N o t to s c a le
Diffuse reflection
Material Description
Winter Snow and IceVegetation (The Average Value of Many Types)SoilSiltSandGypsumClayDirtShale, CoralConcrete, AsphaltCoal Tar PitchPlywood, UnpaintedBrick, RedBark
DR.
0.850.500.05 - 0.35 0.20 - 0.400.10 - 0.35 0.55 - 0.700.40 - 0.500.30 0.45 0.10 0.05 0.50 0.250.20 - 0.25
904 nm diffuse fractional reflections of common material
A B C
DE F
Common Type of Reflector Laser Rangefinder
A. Laser Atlanta Advantage CI B. Riegl Scout. C. Leica Binocs.D. Laser Atlanta Advantage CI with PRO XL DGPS. E. LaserTech Criterion. F. LaserTech Impulse.
Manufacturer Con. Max. Range(m)
Comp. Encoder Hor., Ver; Range(m)
Laser Atlanta yes 500 yes yes 0.1-0.5;0.2;0.15MDL yes 100-500 yes yes 0.1-0.5;0.2;0.15ALS(MDL+LA) yes 500 no Theod 0.01;0.01;0.15ALS(MDL+Riegl) yes 1000 no Theod 0.01;0.01;0.15Laser Tech. no 2200 yes no 0.5;0.2;0.15Leica no 100 yes no 0.5;0.1;0.15Riegl Can 700 no no ?;0.2;0.15
Total Station May 100-200 no Theod 0.01;0.01;0.01
Characteristics of common types of laser rangefinders
ALS = MDL theodolite with a Laser Atlanta (LA) or Riegl laser rangefinder.
