LIDAR Provides Highly Accurate Land Surface Elevations for Seismic Exploration
On seismic projects, the use of LIDAR can result in extensive operational cost savings and improvements in data quality.
In many environments, LIDAR can make a significant contribution toward conducting a successful seismic program.
Seismic projects typically cover tens to
hundreds of square miles and consist of hundreds of source and receiver points wthin each square mile. Surveying each point
is a requirement to obtain an accurate position and elevation. Projects of this magnitude require extensive planning, scheduling,
and communication resulting in a constant need for a variety of surface maps and models. LIDAR is a tool providing multiple
benefits for such operations, especially in areas of rough terrain.
LIDAR accurately measures surface elevation using a laser scanner mounted
on an aircraft producing high-resolution Digital Elevation Models (DEM’s) depicting ground and vegetation surfaces.
Applications
of LiDAR products to land seismic acquisition operations:
Slope determination - preplanning of source locations, source
type identification, locating staging areas, positioning crews to work in downhill directions and illustrating regulation
compliance.
Survey
efficiency – using LiDAR derived elevation (Z) value for seismic points, instead of acquiring Z with Global
Positioning System (GPS) units, can increase the efficiency of survey crews, especially in areas of heavy vegetation. Provides
elevation values at given locations.
Identification of operational hazards – steep terrain, thick vegetation and oilfield infrastructure
such as pipelines, well pads and roads
Map creation – LiDAR DEM’s serve as a map backdrop, contours, slope maps, and 3D digital
terrain models (DTM)
Radio
communication - Radio Frequency (RF) shadow zone models, radio transmission and reception models help locate ideal
signal repeater locations
Logistical and safety planning – fly-through simulations on DTM’s provide a visualization
of ground conditions and hazards that occur on any travel route
Using LIDAR and aerial imagery, map layers can be created to include theoretical
“preplot” source locations, hazards and avoidance areas. Based on the LiDAR data, layers depicting slopes exceeding
14 degrees and heavy vegetation can be created.
Where necessary, source points can be moved from areas requiring heliportable drilling
to areas accessible by buggy drills or vibrators. The new locations of moved points can be provided to the survey crew.
The ability to preplan offers several advantages
over making source point moving decisions in the field. It is easier to monitor the source point distribution required to
maintain adequate geophysical coverage. When relocating points in the field, it is often difficult to judge slope angles and
direction the points should be moved. Additionally, hazardous steep slopes could be avoided entirely.
Reduce
Costs
This process can
be beneficial to provide accurate elevation values for re-positioned points while avoiding costly and hazardous re-surveying.
Number of source points that may require heliportable-drilling in their preplot positions on steep terrain or in heavy vegetation
can reduce the final number of heliportable points, resulting in drilling cost savings.
The accuracy of lidar data is in the region of 6 inches absolute and closer relative. This means, from lidar point to
lidar point, the data is usually within 2-3 inches in accuracy. However, compared to local geodetic benchmarks (ground control)
the absolute accuracy of any point is around six inches in open clear areas and somewhat less in areas of heavy vegetation.
When collected at the same time as high-resolution aerial imagery, the combination of LIDAR with digital ortho-imagery provides
considerable benefits in downstream operations including planning rig sites, roads, pipelines and flow simulation modeling,
much of which can be done without actually leaving the office.
About
Spatial Resources:
We live in a 3-dimensional, spatial world and increasingly we require accurate 3D, digital
representation of our projects, sites and facilities. If your business requires accurate measurements, surveys and spatial
information, Spatial Resources can provide savings in cost, time and elimination of risk through our network of LIDAR, surveying,
mapping, and laser scanning service providers.
Spatial Resources, LLC is
a spatial advisory practice providing solutions tailored specifically to your spatial information needs. Successful projects
require custom, site specific, project specific spatial information solutions, Spatial Resources’ mission is to provide
you “The right expertise, in the right place at the right time.”
For more information about Spatial Resources’ aerial LIDAR mapping capabilities, please contact Roland Mangold
at 720-934-2482, or by email at info@spatialresources.com 
