After completing my session
on the “Prehistoric places in Kongu Region”, organized by Tamil wiki – Thooran Viruthu
Vizha 2025, on 16th August 2025 at Kavundachipalayam between Erode
and Chennimalai, Mr. Krishnan told me about this menhir and the article written
by Mr. Jayamohan. In the article, Mr. Jayamohan mentioned this menhir and pointed out that the same was not documented in our blog. So decided to visit this menhir along with
Mrs. Sakthi Prakash, co-author of my blog, at Chinnathambipalayam, near Tiruchengode, and Mr. Krishnan
also arranged a vehicle. This Menhir is on the bus route from Tiruchengode to Salem,
about 5 km from Tiruchengode.
The flat rock is about
8 feet wide and 15 feet high, and its thickness is about a foot. Cracks are also
observed on the surface. Mud pots are found on the base of the flat rock. It was
said that the locals worship this rock is considered Kattu Karuppasamy. A similar structure of rocks is found on the edge of the field and in some other spots in
the surrounding villages.
We had a doubt that
this standing flat rock may not be a Menhir; instead, it must be a natural rock.
Similar rocks are standing at the edge of the field, but they are shorter. Also, we couldn’t
find any evidence to prove it is a Menhir. Certain criteria are missing.
Ancient red and black pot shards around this place, cairn circles in this area,
or nearby Villages, water sources like ponds / eri, etc., are missing. So this
is not a menhir, and this is a natural formation of rock.
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In this connection, we thought of getting an opinion from a Geologist to support our conclusion. The
expert’s opinion is also given below.
THE OPINION OF Mr.
SHRIDHAR GANAPATHY, GEOLOGIST.
Veludharan Sir,
Happy to interact
with you.
You had raised a
query whether the rocks shown in the picture sent by you are Menhirs or in situ rocks?.
You also informed
during the discussion that Rocks used for Menhir monuments could be stones that
are brought from a distant place
or
In certain cases, if
rocks are available in close vicinity, a Menhir is constructed using the same
rock material.
OBSERVATION
From the pictures
supplied, we could make two sets of rocks. One is called mother rock, or the
earlier-formed rock. (In the schematic drawing, shown in blue, and in the
picture with a soil layer probably having fewer nutrients, where plantations like
groundnuts are grown, indicative of less availability of water.
The original country
rock type is non-identifiable, as the rock is highly weathered to form a soil
layer.
The second type of
rock, as seen in the picture, is known as Migmatites. This is relatively a later
formation compared to the country rock. This can be identified as wavy-like
(striated rock), which comes under the broad classification of metamorphic
rocks. The rock has quartz, Feldspar, and Biotite (black in color and flaky in
nature). In the schematic drawing, it's Red in color.
Inference
Having explained the
rock feature as seen in the picture, one could conclude the Migmatite as a
metamorphic intrusive. To put it in a simpler way, Migmatites, in Fluid or semi-fluid form, were injected into the already solidified earlier country rock through a weaker plane. This is seen clearly in the field with a certain linear
orientation.
The country rock is
seen as a soil formation, as it is an older formation. Hence more prone to
weathering. This rock may also be relatively soft, hence more
subject to weathering, giving rise to soil formation. It is difficult to make
out what type of rock, before it changed to soil form from the picture.
The younger rock (Migmatite),
which was in a Fluid form, got injected into the solid country rock. Over a
period of time, this migmatite solidified.
Since it is a younger
formation and also probably more resistant to weathering, it stands out, whereas the country rock has weathered, giving rise to soil formation, and hence is used for
farming.
Conclusion:
Migmatites,
protruding rocks which have a particular orientation, show varying degrees of
weathering, whereas the country rock, being an older formation, is probably more
resistant and stands out. Differential weathering shows as individual tabular
structures and, in certain areas, well-formed, identifiable rocks.
Hence, what we see is a natural rock formation and not a Menhir.*
Of course, taking
advantage of the raised rock formation of Migmatites, our ancestors could have
built a Menhir, which I feel a trained Archaeologist could say with additional
field evidence (if available)
Veludharan Sir, please
call me if you need clarification.
Regards
Shridhar Ganapathy
GEOLOGIST.
Migmatite rock
exposure. Migmatite shows prominent black streaks of Biotite
minerals. Pink and white minerals in the migmatite rock could be Feldspar and
quartz. This rock bed shows less weathering. Pl notice the rock bed, which shows a
prominent orientation, indicated by an arrow mark.
Migmatite intrusive
rock stands as a resistant wall. The adjoining field represents the older country
rock. See the orientation of rocks and Biotite streaks indicated by the arrow
Resistant Migmatite
intrusive (metamorphic rock) as a wall, along with weathered country rock soil,
supports the vegetation. See a marked orientation of the Migmatites
Long shot, gives the
orientation of the migmatite intrusive. Pl enlarge the picture to visualize the
migmatite orientation.
Weathered
Migmatites, giving rise to individual slabs and boulders.
Schematic sketch to
explain the geological process that gave rise to Migmatites (which are seen in
the field as beds, slabs, and isolated boulders).
LOCATION OF THE
SITE: CLICK HERE
--- OM SHIVAYA NAMA
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