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There is a possibility that extreme aridity during the
terminal Pleistocene and development of hypersaline con-
ditions in the playas, formed by tectonic activity in the
region, have caused the deposition of older gypsum depos-
its like that of Jamsar in the region. The findings point
toward the existence of an advanced civilization, possibly
the Vedic civilization, which is much older than the Har-
appan and the Indus Valley civilizations. Dating of the
sample will open up new avenues to search for a civiliza-
tion in the region even older than the Mesolithic sites of the
early Holocene period with the ceramic tradition in the
Thar Desert of India and Pakistan or that of Mehrgarh
settlements at the foot of the Kirther Hills, dating back to
9.0
-
5.5 ka [Valdiya, 2002].
The early Harappan sites [Kenoyer, 1998] have been ex-
cavated at Balakot, Amri, and Kot Diji in the Sindhu
mum, there were abrupt climatic
fluctuations in the region
[Swain et al., 1983; Fleitmann et al., 2003; Phadtare, 2000;
Sinha et al., 2005].
The area west of the Aravalli Mountain Range is occupied
by several saline lakes and evaporite deposits of the Quater-
nary period producing a large quantity of different salts.
Different opinions have been put forward to explain the
origin of salt and saline lakes in the region [Paliwal, 1982],
including neotectonic disturbances resulting in drainage dis-
organization, reversal, and at places blocking, causing the
formation of saline lakes [Paliwal, 1986; Roy, 1999]. Con-
sidering the enormous quantity of salt produced from these
lakes, we will have to account for its source. The
Na
+
”
component of
“
NaCl
”
might have been derived from the
surrounding rocks, but the atmosphere is the only source for
“
“
ood-
plain; Saraikhola Gulma near Taxila in Peshawar plain;
Hakra Valley in Cholistan; Kunal, Kalibangan, Banawali,
and Rakhigarhi in the Sarasvati plain; and Sothi, Siswal, and
Mitathal in the Drishadvati plain. The Harappan civilization
[Kenoyer, 1998], named after the type of area near the Ravi
River, had an agrarian base. Important sites are Kalibangan
and Baniwal on the bank of the Sarasvati River; Mohenjo-
daro in the Sindhu Valley; Harappa on the bank of the Ravi
River; Dholavira in Kutch; and Lothal at the Khambhat coast
[Kenoyer, 1998; Cullen et al., 2000; Possehl, 2002; Madella
and Fuller, 2006].
cult to account for a huge deposit of
salt in these lakes in a short time [Paliwal, 2008]. The oldest
sediments in these lakes have been dated at more than 12,820
years B.P. [Wasson et al., 1983]. There is a possibility that
these inland basins had connections with the seawater
through trenches developed during neotectonic activity [Pa-
liwal, 2008]. Alternatively, these saline lakes located at the
junctions of deep-seated subvertical faults (Figure 3) have
groundwater connections with the older evaporates (Hanseran
Group of the Marwar Supergroup and Tertiary) situated
below the region. Salt moves through these faults when the
lakes are
Cl
,
”
and it is bit dif
filled with the rainwater and gets evaporated, pre-
cipitating salt on desiccation [Paliwal, 2008].
7. HOLOCENE CLIMATIC CHANGES
8. CONCLUSIONS
The region to the west of the Aravalli Mountain Range
and south of the western Himalaya experienced desert con-
ditions as long ago as 200,000 years B.P. with several
intermittent glacial and interglacial phases. A moist and
humid climate most suitable for habitation prevailed be-
tween 40,000 and 20,000 years B.P. The Last Glacial Max-
imum (a period between 18 and 25 ka) left its signature in
the region. Major deglaciation transition occurred between
12,000 and 13,000 years B.P. Deglaciation intensi
flourished along the banks of the
Sarasvati River, and the saline lakes were formed by neotec-
tonic disturbances resulting in drainage disorganization and
blocking. In these circumstances the Sarasvati River and the
Vedic civilization that
The Vedic civilization
flourished along its banks must date
back to more than 12,820 years B.P. The region suffered
abrupt climatic changes, re
ected in lowering of sea level at
the west coast of India by 100 m around 14,500 years B.P.
and rising by 80 m by 12,500 years B.P. Neotectonic dis-
turbances in the region that took place at 10,000 years B.P.
were accompanied by an intense southwest monsoon. The
Sarasvati River system was being repeatedly flooded, and
this caused the end of the Vedic civilization, a civilization
much older than the Harappan and the Indus Valley civiliza-
tions. The Sarasvati River, mentioned in the Vedas written by
Indian scholars, continued until the Southwest Monsoon
became weak at the beginning of the Puranic era (5000 to
2500 years B.P.). This was the time of Mahabharata (about
5238 years B.P.), at the end of which the Sarasvati River also
disappeared from the scene.
cation
of the Southwest Monsoon occurred at 12,000 years
B.P., peaking between 9000 and 6000 years B.P. [Swain
et al., 1983; Fleitmann et al., 2003; Phadtare, 2000; Sinha
et al., 2005; Rashid et al., 2007; Valdiya, 2010]. Ultimately,
the Southwest Monsoon became weak at 5000 years B.P.
Onset of an arid climate in the region began approximately
3500 years B.P., which began the decline of the Indus Valley
civilization. Since then the present arid conditions have
prevailed. Figure 9 depicts the lake level reconstruction of
Didwana Lake and inferred climatic changes [Singh et al.,
1990]. Sediments of all the saline lakes in the region depict
identical climatic conditions. After the Last Glacial Maxi-
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