First petrological results along the traverse
(Sol 1 to 57):
Diamonds in the basalt-like boulders
My first Analysis
stones at the rover's landing area were zoomed in with the mast camera or
shot at with a laser beam. The results published so far are modest.
There is talk of basaltic material But that is not certain.
Frst datasets from the Visible and InfraRed (VISIR) sensor and Raman
spectrometer instruments of the of the SuperCam were now published. VISIR
uses reflected sunlight to examine the mineral compositions of rocks and soils.
The Raman spectrometer uses a green laser beam for its observations. The
result: Clear peaks of Mg-carbonate
were found in the spectrogram from an outcropd basaltic pumice-like stone
in the ground (Sol 12).
An exposed rock (Sol-37)
is particularly noticeable and is described as puzzling. It has a smooth surface
on which numerous rounded depressions can be seen.
Upon closer inspection of the published photo, I notice that some of the depressions
still have a brownish (not secondary) filling. Obviously these are the typical
remains of disintegrated olivine aggregates,
which are already missing in most of the holes.
The special density of the "basalt" groundmass (no mineralization can be recognized)
indicates a volcanic origin in which the lava cooled down very quickly.
The olivines were already present as phenocrysts in the lava.
Another special feature that has not yet been commented on are the streaks
or nests with bright inclusions (crystals)
in the dense groundmass of the stone.
Such bright inclusions can also be seen in other photographed stones.
It is now clear that these bright crystals, which are frequent in other
angular boulders, not occur in the pumice-like deposits in the bottom of the
In any case, the free, mostly angular boulders do not belong to the crater
floor and were part of the eroded delta. They come from outside the crater
and were transported by the moraine of a glacier.
The latest photos suggest an internal columnar-like
structure, at least in parts of the basalt.
It is becoming increasingly clear that the bright crystals only occur in the
basalt and the sintered contact zone between basalt and crust. The crystals
in small stones on the ground result from the disintegration of columnar-like
parts in the basalt or from the contact zone to the crust.
Zoom with the SuperCam on a stone in the ground that is identified
as basaltic (?). Clear peaks of Mg-carbonate
were found in a spectrogram.
Zoom with the SuperCam
on free stone with the supposed weathering crust:
of the bright, reflective crystals in a sunken boulder.
If we study the spectrogram of Sol-12 again,
we notice a peak that signals hydrogen-carbon.
It could mean that the bright, reflective inclusions are
diamonds. On the outer surfaces of the
crystals, which have free atoms, is docked the hydrogen.
It is now clear
that the bright crystals also occur in small aggregats on the soil.
But it is not yet clear whether it is pumice or comes from the crust
of the boulders.
A mysterious holey "basalt" boulder (15 cm) from the eroded
part of the delta. Again the
bright inclusions in the stone.
The smooth surface of the stone is striking. No crystallization
can be seen, which indicates a rapid cooling of the magma after a volcanic
The holes: Decomposed and blown out phenocrysts
Again a boulder
with bright inclusions. So far, however,
an interpretation by the specialists at NASA is missing.
A stone related
to that of Sol-37 ?
An angular boulder,
as occurs in heaps on soil elevations,
with a knobby crust, similar Sol-16.
from boulders on sandy elevation.
What is it ? Basalt with a ash crust ?
There is great
interest in the bright, reflective crystals. This stone was examined
more closely with the SuperCam.
Bright crystals can be seen on parts of the surface (contact zone between
basalt and sintered crust ?
The interest is
in the broken sides of the stones with the strange "shell-like marks".
Stones in the heap
are further examined for details.
Small holes in the basalt are apparently related to the knobby
crust (consisting of aggregates) which can peel off, but is connected
with the basalt as sinter (ash ?).
selection of other interesting details to solve the ongoing puzzle to
the origin of the boulders.
Some fractures in basalt shows probably an internal
columnar-like structure (!). This also
explains the friable decay of some parts of the basalt. That explains
also the "shell-like marks" on broken basaltic boulders.
It is becoming increasingly clear that the bright crystals only occur
in the basalt and the sintered contact zone between basalt and crust.
The crystals in small debris on the ground result from the disintegration
of columnar-like parts in the basalt or from the contact zone to the
The light-colored pumice deposits in the ground are free of crystals.