Contacts

Identifiers and Keywords

ANZLIC Id

ANZVI0008102999 

Topic category

• Elevation

Resource Constraints

Use limitation

General 

Classification

Unclassified  

Other Dataset Details

Format

ESRI Ascii 

Spatial

Spatial representation type

Grid  

Reference system identifier

MGA Zone 55 GDA94

Resolution

Horizontal Accuracy

0.3m  

Vertical Accuracy

0.1m  

Row Resolution

1cm  

Column Resolution

1cm  

Quality

Conceptual Consistency

Meets all specifications and adheres to format and naming standards. An assessment of the merged tiles for DTM consistency was undertaken across all project edges. In general the edgematching was adequate and any stepping between source datasets is within reasonable limits. However, in one particular instance, the redevelopment and widening of the Midland Highway between the dates of the 2 LiDAR surveys in question has resulted in a significant step (>0.25cm and up to 0.6m) in the merged product. This is an unfortunate and unavoidable effect of mergeing data over changed land surfaces. 

Missing Data

This data set represents the edge tiles of the original AOI that have overlap with adjacent projects.The tiles are full with respect to data content and consist of merged data from the source project and the adjacent projects. 

Lineage

Description

The surrounding adjacent LiDAR projects incorporated in the merged tiles are: 2011 Melbourne Structural Vegatation LiDAR - Lara, Victorian Coastal LIDAR Level 3 Classification, 2013-14 Geelong-Anakie-Golden Plains LiDAR 1) ArcGIS 10 Terrain Grids were derived using the Natural Neighbor interpolation. This method uses the closest triangles and applies weights to the proportionate areas from the grid cell centroid to interpolate the value. It uses known elevation data, it does not make any predictions regarding the surface and accurately depicts existing troughs and peaks in the data and supports irregular point spacing, which suits the nature LiDAR data. Grids were then translated to ESRI ASCII formats using custom ArcGIS and Feature Manipulation Engine (FME) macros. 2) For comparison, two separate datasets were generated, one referenced to AHD using Ausgeoid09 and a 2nd dataset referenced to AHD using Melbourne Geoid model. The dataset referenced to AHD using Ausgeoid09 reveals a marginally better fit to test points. A tilt in a general east-west direction was observed when the LiDAR data was compared to field test point sites spread throughout the project area. A tilt correction has been applied to both Ausgeoid09 and Melbourne Geoid datasets. 4) Cut lines were used to merge the adjacent datasets together. An overlap of 50m was used between adjacent/overlapping datasets. Cut lines have been made around ground features that have changed between the dates of the new and existing data within overlap areas. New reprocessed data has been kept in preference to existing data. Below are approximate locations of where changes in ground features have occurred. Adjustments to cut lines have been made in these locations: 264590E, 5773165N; 269210E, 5771650N; 270540E, 5757320N; 271690E, 5770390N 

Acquisition Date

Begin date

2012-02-06 

End date

2012-03-09 

Instrument

Name

Optech ALTM Orion 

Type

LIDAR 

Platform Type

Aerial 

Acquisition Data (Common)

Status

complete  

Assembly

Single  

Tile Size

2 km  

Cloud Cover Percentage

0 

Raster Details

Number of Bands

1 

Band List

1  

Resampling Kernel

Cubic Convolution  

Platform Name

Fixed Wing Aircraft  

Seamlessness

Full  

Rectification Type

Orthorectified  

DEM Details

DEM Creator

Supplier  

Aerial Survey Details

Runs

83 

Run Orientation

Various  

Swath Width

807 

Side Overlap

25 

Forward Overlap

100 

Flying Height Unit

agl metre  

Flight Height

1200 

About the Metadata Record

Metadata identifier

452c5857-e4bd-5ea7-b741-4be5c363f161

Resource Type

Dataset  

Date info ( Revision )

2023-03-22T00:22:23

Standard Name

ISO 19115-3:2018 

Profile Name

DELWP Profile 

Profile Version

Version 1 

Profile Date

2019-05-24  

Metadata Constraints

Classification

Unclassified