Desalination plant diffuser ports rising 1-2 m out of the seabed form the “eyes” of two friends engaged in conversation, according to this slope-based interpretation of the seabed at Kurnell, Australia. Large sandstone cliffs and intertidal shelves, characteristic of the dramatic Sydney coastline, continue into the subtidal realm and provide complex habitat for blue-groper, large hand-shaped sponges and stalked ascidians.
Detailed facial features arise when analyses of slope and rugosity are applied to the bathymetry derived at the site during multibeam surveys in December 2012. Following the high-slope (pink to purple) and convoluted edges of the weathered sandstone, the viewer first sees one face, then two. Both are passive but seemingly in a state of happy contemplation. At second glance, the larger and more obvious face, appears animated, mouth wide, in open discourse with their smaller round-eyed friend.
-34° 01’ 58” S, 151° 13’ 45” E
UTM 56S (WGS 84)
New South Wales Office of Environment and Heritage
MARINE HABITAT MAPPING (www.environment.nsw.gov.au)
GeoAcoustics (Konsberg) 125KHZ Geoswath
Acoustic data processing software
GS+ & QPS Fledermaus
1 ° slope interval over 0.5×0.5 m bathymetry
Tim Ingleton, NSW OEH, Arc (ESRI) 9.3
Tim Ingleton, New South Wales Office of Environment and Heritage