4SM WV2 Geraldton

WV2 at Geraldton sorry: private pages
co-registered images and seatruth profiles courtesy of FUGRO-NPA

TM_20090110
TM_20110116
ETM_20020131
Foul waters

please refer to
Holloway 2006 pdf
CHUA_02_CP.pdf
WesternAustraliaMarineFutures.pdf
srfme_core_BenthicDynamics.pdf

Mumby, P. J., W. Skirving, A. Strong, J. T. Hardy, E. LeDrew, E. H. Hochberg, R. P. Stumpf and L. T. Davind (2004).
"Remote sensing coral reefs and their physical environment."
Marine Pollution Bulletin 48: 219-228.

Only the above two TM images yield "reasonable" results.
They exhibit the same topographic trends and features.
I have managed so that they yield approximayely the same computed depth.

It shall be seen that the WV2 image
does not add any major novel feature to the description below.

A gently sloping rocky platform, 5-10 m deep,
followed by a deeper lagoon ~15 m deep,
and then by a series of rocky reefs,
in potent and complex hydrodynamic conditions.
This is how the litterature describes
the ~ 10 km wide shallow waters
along the coasts of WA.

The above two Landsat images yields results
which nicely fits with this description.

Add to it an ubiquitous cover
of sands, green seagrasses,
brown algae and very dark epiphyts.

Long sand dunes over a rocky platform

A bright bottomed shoal appears on profile_4A, centered at ~9 km.
- It is ~10 km long, ~1.5 km wide, and ~ 4.5 m high.
That's what a submerged sand dune resting on a gently sloping rocky platform would look like, in which case we can't expect it to be stable over time.
But its water column corrected reflectance only reaches 28% of the reflectance of the sand dunes on land: this calls for fairly dark terrigeneous sands and/or partial coverage with seagrass.

Long sand dunes over a rocky platform

Many such dunes are observed, oriented SW-NE.

They seem to evolve as a result of the complex hydrodynamic conditions determined by a deeper lagoon and a series of rocky reefs farther offshore.
They might as well be somehow connected to the sand spits and tombolos which characterize the intertidal domain.

"foul waters/atmosphere"
ETM_20020617.tif
ETM_20030228.tif
ETM_20110820.tif
ETM_20110820.tif

ETM_20020617	ETM_20030228
ETM_20110820	TM_20100505