This data set contains elevation data derived from a lidar survey approximately 300m wide of the Gulf of Mexico shoreline in the
Northeast Lake Como quarter-quadrangle on Galveston Island Texas. The geographic extent of the data set is equivalent to the
quarter-quadrangle plus 30 meters of overedge. The data is created by combining data collected using an Optech Inc. Airborne Laser
Terrain Mapper (ALTM) 1225 in combination with geodetic quality Global Positioning System (GPS) airborne and ground-based receivers.
The Bureau of Economic Geology, the University of Texas at Austin owns and operates an ALTM 1225 system (serial number 99d118).
This system is installed in a single engine Cessna 206 (tail number N4589U) owned and operated by the Texas State Aircraft Pooling
Board. The lidar data described by this document was collected on 18 September 2002 (26102) between 20:34 and 00:08 UTC
(actual data collection). Conditions on that day were low clouds at 335m Above Ground Level (AGL), haze, and occasional showers.
99d118 instrument settings for this flight were; laser pulse rate: 25kHz, scanner rate: 26Hz, scan angle: +/-20deg, beam divergence:
wide, altitude: 300-490m AGL, and ground speed: 70-106kts. Three GPS base stations, 2 Ashtech and 1 Trimble 4000SSI receivers (backup),
were operating during the survey. The three base stations were at the following locations: one 3.5km south of San Luis Pass, one at the
Scholes International Airport Galveston, and one on the seawall at Rollover Pass. This data set consists of 1687100 records of x,y,
and z values. The data set was generated from a larger data set and includes all valid points within the requested geographic bounds.
Original contact information:
Contact Name: Jim Gibeaut
Contact Org: Bureau of Economic Geology University of Texas at Austin
Title: Research Associate
Phone: 512-471-0344
Email: jim.gibeaut@beg.utexas.edu
This data set is an LAZ (compressed LAS) format file containing LIDAR point cloud data.