Lowry Water LiDAR Dataset

Metadata:

• Identification_Information
• Data_Quality_Information
• Spatial_Data_Organization_Information
• Spatial_Reference_Information
• Entity_and_Attribute_Information
• Distribution_Information
• Metadata_Reference_Information

Identification_Information:

Citation:

Citation_Information:

Originator: Utah State University LASSI Service Center

Publication_Date: 20120227

Title: Lowry Water LiDAR Dataset

Geospatial_Data_Presentation_Form: mass points (.las 1.2 format)

Description:

Abstract:

The Lowry Waters Digital Surface Model data set is a mass point dataset composed of LiDAR point data. This data set was collected from airborne surveys completed in September and October 2011 and covers approximately 59 square miles on the borders of Emery and Sanpete Counties near Spring City, UT. Point data is organized into fifty-nine (59) 2km by 2km tiles, stored in LAS 1.2 format. The LiDAR point clouds are classified into standard classifications. Contained in this dataset are two sets of tiles. One containing all points, and another contianing a subset of points representative and classified as ground or bare earth.

Purpose:

To create a high-accuracy digital terrain model for terrain analysis and other mapping applications for the Utah Automated Geographic Reference Center (AGRC).

Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 20110926

Ending_Date: 20111024

Currentness_Reference: publication date

Status:

Progress: Complete

Maintenance_and_Update_Frequency: Unknown

Spatial_Domain:

Bounding_Coordinates:

West_Bounding_Coordinate: -116.27344

East_Bounding_Coordinate: -111.22690

North_Bounding_Coordinate: 39.51119

South_Bounding_Coordinate: 39.38515

Keywords:

Theme:

Theme_Keyword_Thesaurus: none

Theme_Keyword: Light Detection and Ranging

Theme_Keyword: LAS

Place:

Place_Keyword_Thesaurus: none

Place_Keyword: Utah

Place_Keyword: Sanpete County

Place_Keyword: Emery County

Access_Constraints: None

Use_Constraints:

None. This project was completed for the Utah AGRC and will be placed in the public domain.

Point_of_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: Utah State University LASSI Service Center

Contact_Person: Dr. Robert T. Pack

Contact_Position: Director - LASSI Service Center

Contact_Address:

Address_Type: Mailing Address

Address: 4110 Old Main Hill

City: Logan

State_or_Province: UT

Postal_Code: 84322-4110

Country: USA

Contact_Voice_Telephone: (435) 797-7049

Contact_Electronic_Mail_Address: robert.pack@usu.edu

Data_Quality_Information:

Logical_Consistency_Report:

This dataset contains classified LiDAR mass points for all points acquired during the survey period. These points are representative of bare earth, vegetative cover and manmade structures. An additional dataset containing a subset of points that represent the bare earth or ground classification is also included. Both datasets cover the entire extent of the project area (approx. 59 sq. miles).

Completeness_Report:

LiDAR point cloud data has been processed and classified using Terrascan (Terrasolid.fi) for a 59 square mile portion of the Manti-Lasal National Forest, near Lowry Top Peak. Processing was completed at Utah State University - LASSI Service Center.

Positional_Accuracy:

Horizontal_Positional_Accuracy:

Horizontal_Positional_Accuracy_Report:

Horizontal positional accuracy was not formally tested in this project and was not a specification of this contract.

Quantitative_Horizontal_Positional_Accuracy_Assessment:

Horizontal_Positional_Accuracy_Value: .5 m

Horizontal_Positional_Accuracy_Explanation:

Horizontal positional accuracy was not formally tested in this project and was not a specification of this contract.

Vertical_Positional_Accuracy:

Vertical_Positional_Accuracy_Report:

The Lowry Water project area is remote and therefore finding a GNSS base station control point close enough to the area to enable convenient RTK GNSS field truthing was problematic. It was therefore proposed and accepted by AGRC that a 5’ diameter LiDAR target be used as a spot check. This target was placed next to the SPRING NGS monument near Spring City (see Figure 3). The strategy was to fly over the base station enroute to the Lowry Water flightlines and compare the height of the target (leveled from SPRING) with the LiDAR point(s) that fell on the target Queries show the data for three LiDAR shots, two of which landed on the target (circle) and one of which landed on the SPRING NGS monument. The two shots on the target are at 1771.34 m and the one on the monument is at 1770.64. This difference in height sensed by the LiDAR is within one centimeter of being the same as that measured by the survey level in the field. This indicates relative accuracy well under the 7.0 cm USGS standard requirement.

Quantitative_Vertical_Positional_Accuracy_Assessment:

Vertical_Positional_Accuracy_Value: .07 m RMSEz fundamental vertical accuracy

Vertical_Positional_Accuracy_Explanation:

Vertical Position Accuracy was tested by comparing LIDAR target points to a known GNSS base station coordinate resulting in a reported accuracy of: <0.01 m RMSEz relative accuracy, and a 0.07 m RMSEz fundamental vertical accuracy.

Lineage:

Source_Information:

Source_Citation:

Citation_Information:

Originator:

Utah State University - LASSI Service Center Dr. Robert T Pack ed.

Publication_Date: 20120227

Title: Lowry Waters LIDAR Dataset

Geospatial_Data_Presentation_Form: Mass Points in LAS 1.2 data format

Publication_Information:

Publication_Place: Logan, Utah

Publisher: Utah State University, LASSI Service Center

Type_of_Source_Media: digital

Source_Time_Period_of_Content:

Time_Period_Information:

Range_of_Dates/Times:

Beginning_Date: 20110926

Ending_Date: 20120227

Source_Currentness_Reference: See Date of Publication

Source_Citation_Abbreviation: Lowry Waters LiDAR

Source_Contribution: LIDAR processing

Process_Step:

Process_Description:

Raw LiDAR data was collected using a Riegl LMS Q560 laser scanner equipped with an airbourne GPS/IMU system. A single ground basestation collecting GNSS data on one-second epochs was occupied during the flight. This station was within 30 km of the study area. Thirty-five (35) flight lines were flown over a period of 2 days (not consecutive). Flight lines with a 40% sidelap were flown at approximately 750 m AGL with a nominal spacing of 462.9 meters. Flight lines were flown at approximately 118.8 knots with a swath angle of 60 degrees, resulting in a shot density of 1.4 shot/sq. meter.
After each flight, all raw navigation data, raw LiDAR data, raw image data, coverage data, and flight logs were offloaded for storage and backup. LiDAR waveform files were analyzed using RiAnalyze software to discriminate data points. These points are output in the internal coordinate system of the LIDAR scanner. Each data point is assigned an echo value in preparation for point classification. RiProcess uses the trajectory files created from the raw navigation files to generate XYZ points in a world coordinate system. A boresite calibration and stip alignment is performed in RiProcess to improve data accuracy. Each flight line was processed independently. Each flightline was then brought into Terrascan (by TerraSolid: terrasoli.fi) in the project datum and coordinate sytem. The flightlines were combined and organized into a 2000 meter by 2000 meter tile structure where classification routines were performed (customized to the this project) to classify the points into standard ASPRS/LAS default classifications. A Triangular Irregular Network (TIN) and associated contours were then generated using the final bare-earth data and checked for quality.

Process_Date: 201202

Spatial_Data_Organization_Information:

Indirect_Spatial_Reference:

Lowry Waters LiDAR data are organized into fifty-nine (59) two (2) km square tiles covering the extent of the project area.

Direct_Spatial_Reference_Method: Point

Point_and_Vector_Object_Information:

SDTS_Terms_Description:

SDTS_Point_and_Vector_Object_Type: String

Point_and_Vector_Object_Count: 331,550,495.00

Spatial_Reference_Information:

Horizontal_Coordinate_System_Definition:

Planar:

Grid_Coordinate_System:

Grid_Coordinate_System_Name: Universal Transverse Mercator

Universal_Transverse_Mercator:

UTM_Zone_Number: 12N

Transverse_Mercator:

Scale_Factor_at_Central_Meridian: .9996

Longitude_of_Central_Meridian: -111

Latitude_of_Projection_Origin: 0

False_Easting: 500000

False_Northing: 0

Planar_Coordinate_Information:

Planar_Coordinate_Encoding_Method: coordinate pair

Coordinate_Representation:

Abscissa_Resolution: 0.01 m

Ordinate_Resolution: 0.01 m

Planar_Distance_Units: meters

Geodetic_Model:

Horizontal_Datum_Name: North American Datum of 1983

Ellipsoid_Name: Geodetic Reference System 80 (GRS 80)

Semi-major_Axis: 6378137

Denominator_of_Flattening_Ratio: 298.257222

Vertical_Coordinate_System_Definition:

Altitude_System_Definition:

Altitude_Datum_Name: North American Vertical Datum of 1988 GEOID09

Altitude_Resolution: .01 m

Altitude_Distance_Units: meters

Altitude_Encoding_Method:

Explicit elevation coordinate included with horizontal coordinates

Entity_and_Attribute_Information:

Overview_Description:

Entity_and_Attribute_Overview:

This data set contains elevation values in meters (NAVD88 on Geoid 09) and encoded values for easting and northing on NAD83 (1986). No attached attribute tables.

Entity_and_Attribute_Detail_Citation: USGS

Distribution_Information:

Distributor:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: Utah AGRC (Automated Geographic Reference Center)

Contact_Address:

Address_Type: mailing

Address: 1 State Office Building, Room 5130

City: Salt Lake City

State_or_Province: UT

Postal_Code: 84114

Country: USA

Contact_Voice_Telephone: (801) 538-3665

Distribution_Liability: The data have no implied of explicit guarantees

Metadata_Reference_Information:

Metadata_Date: 20120127

Metadata_Contact:

Contact_Information:

Contact_Organization_Primary:

Contact_Organization: Utah State University - LASSI Service Center

Contact_Person: Dr. Robert T. Pack

Contact_Address:

Address_Type: mailing

Address: 4110 Old Main Hill

City: Logan

State_or_Province: UT

Postal_Code: 84322

Country: USA

Contact_Voice_Telephone: (435) 797-7049

Metadata_Standard_Name: FDGC Metadata

Metadata_Standard_Version: FGDC-STD-001-1998

Metadata_Language: English