Shrunken heads at Endurance Crater (MER)

Have a look at the structures in this image taken Thursday by Opportunity.
They look like what is left over when you pull the forms off a cement slab.
Although incredibly fragile looking, they stand upright and are lined up
almost perfectly linearly. Reminiscent of the Easter Island sculptures in
miniature. Any idea what might have caused them. Perhaps a fracture from
the impact that formed the crater? Erosion by water or maybe sediment
caried by water and slapped up against a flat rock? It sees like they were
up against something of different composition with a straight edge that is
now gone.

http://marsrovers.jpl.nasa.gov/gallery/all/1/p/162/
1P142569631EFF3221P2387L7M1-BR.JPG

try again with the url, it does not work
cheers, john

try again with the url, it does not work
cheers, john

john fletcher wrote:

try again with the url, it does not work
cheers, john

Url works. You have to copy & paste.

john fletcher wrote:

try again with the url, it does not work
cheers, john

Url works. You have to copy & paste.

On Sat, 10 Jul 2004 07:47:35 -0500, mlm wrote:

Have a look at the structures in this image taken Thursday by Opportunity.
They look like what is left over when you pull the forms off a cement slab.
Although incredibly fragile looking, they stand upright and are lined up
almost perfectly linearly. Reminiscent of the Easter Island sculptures in
miniature. Any idea what might have caused them. Perhaps a fracture from
the impact that formed the crater? Erosion by water or maybe sediment
caried by water and slapped up against a flat rock? It sees like they were
up against something of different composition with a straight edge that is
now gone.

http://marsrovers.jpl.nasa.gov/gallery/all/1/p/162/
1P142569631EFF3221P2387L7M1-BR.JPG

It looks like harder rock left where erosion took the rest.

--
Marilee J. Layman

On Sat, 10 Jul 2004 07:47:35 -0500, mlm wrote:

Have a look at the structures in this image taken Thursday by Opportunity.
They look like what is left over when you pull the forms off a cement slab.
Although incredibly fragile looking, they stand upright and are lined up
almost perfectly linearly. Reminiscent of the Easter Island sculptures in
miniature. Any idea what might have caused them. Perhaps a fracture from
the impact that formed the crater? Erosion by water or maybe sediment
caried by water and slapped up against a flat rock? It sees like they were
up against something of different composition with a straight edge that is
now gone.

http://marsrovers.jpl.nasa.gov/gallery/all/1/p/162/
1P142569631EFF3221P2387L7M1-BR.JPG

It looks like harder rock left where erosion took the rest.

--
Marilee J. Layman

"mlm" skrev i en meddelelse
...
Have a look at the structures in this image taken Thursday by Opportunity.
They look like what is left over when you pull the forms off a cement
slab.
Although incredibly fragile looking, they stand upright and are lined up
almost perfectly linearly. Reminiscent of the Easter Island sculptures in
miniature. Any idea what might have caused them. Perhaps a fracture from
the impact that formed the crater? Erosion by water or maybe sediment
caried by water and slapped up against a flat rock? It sees like they
were
up against something of different composition with a straight edge that is
now gone.

http://marsrovers.jpl.nasa.gov/gallery/all/1/p/162/
1P142569631EFF3221P2387L7M1-BR.JPG

It reminds me of a 'largescale' clayskins in gleyed soils.
I cannot make anything like it work with normal erosional/sedimentary
processes working on an open post-impact crack, and speculates weather the
fracture and the mineralisation or skin have formed before the impact.
Except for the origin of the crack, it should not pose a problem that the
destruction of the impact follows predefined weaknesses in the rock. I think
that it is reasonable to expect water, one way or the other, the mean of
transport of the minerals involved, but it still leaves an array of
posibillities. There is something in 'water', 'fine mars-dust' ( finegrained
smectitic clay in water) a crack and perhaps repeated wetting and drying
before water leaves for good that matches a developement of clayskin on a
ped (red iron on peds may also precipitate in else grey soil).
I do expect a mineralogist to post an alternative explanation though.
Someone used to mineralisations in veins may have a better key to the
problem.

Carsten

"mlm" skrev i en meddelelse
...
Have a look at the structures in this image taken Thursday by Opportunity.
They look like what is left over when you pull the forms off a cement
slab.
Although incredibly fragile looking, they stand upright and are lined up
almost perfectly linearly. Reminiscent of the Easter Island sculptures in
miniature. Any idea what might have caused them. Perhaps a fracture from
the impact that formed the crater? Erosion by water or maybe sediment
caried by water and slapped up against a flat rock? It sees like they
were
up against something of different composition with a straight edge that is
now gone.

http://marsrovers.jpl.nasa.gov/gallery/all/1/p/162/
1P142569631EFF3221P2387L7M1-BR.JPG

It reminds me of a 'largescale' clayskins in gleyed soils.
I cannot make anything like it work with normal erosional/sedimentary
processes working on an open post-impact crack, and speculates weather the
fracture and the mineralisation or skin have formed before the impact.
Except for the origin of the crack, it should not pose a problem that the
destruction of the impact follows predefined weaknesses in the rock. I think
that it is reasonable to expect water, one way or the other, the mean of
transport of the minerals involved, but it still leaves an array of
posibillities. There is something in 'water', 'fine mars-dust' ( finegrained
smectitic clay in water) a crack and perhaps repeated wetting and drying
before water leaves for good that matches a developement of clayskin on a
ped (red iron on peds may also precipitate in else grey soil).
I do expect a mineralogist to post an alternative explanation though.
Someone used to mineralisations in veins may have a better key to the
problem.

Carsten

mlm wrote:

Have a look at the structures in this image taken Thursday by Opportunity.
They look like what is left over when you pull the forms off a cement slab.
Although incredibly fragile looking, they stand upright and are lined up
almost perfectly linearly. Reminiscent of the Easter Island sculptures in
miniature. Any idea what might have caused them. Perhaps a fracture from
the impact that formed the crater? Erosion by water or maybe sediment
caried by water and slapped up against a flat rock? It sees like they were
up against something of different composition with a straight edge that is
now gone.

http://marsrovers.jpl.nasa.gov/gallery/all/1/p/162/
1P142569631EFF3221P2387L7M1-BR.JPG

My guess is that they are remnants of solution that seeped into cracks
between the fractured blocks of salty material in the crater and
hardened. Later, the soft, salty material eroded down from the sand
blasting effect of wind, but this material was just a bit harder than
what was originally cracked, so it is left standing above the
surrounding surface.

--
John Popelish