Abstract:Sediment production and its subsequent preservation in the marine stratigraphic record offshore of large rivers are linked by complex sediment-transfer systems. To interpret the stratigraphic record it is critical to understand how environmental signals transfer from sedimentary source regions to depositional sinks, and in particular to understand the role of buffering in obscuring climatic or tectonic signals. In dryland regions, signal buffering can include sediment cycling through linked fluvial and eolian … Show more
“…It is noteworthy that the reconstructed Ghaggar isotope trend of Singh et al (2016) is similar both in direction and timing, as well as depth, as that seen at Marot (Fig. 2), downstream of their drill sites (East et al, 2015), as well as at the much more distant section at Kanpur analyzed by Rahaman et al (2009), and which was already highlighted in their study. Indeed, if we plot the isotope character of the floodplains of the Hakkra River (downstream equivalent of the Ghaggar in modern Pakistan) near Marot we see that they form as single progressive trend, culminating in ε Nd values of -13 to -14 ( Fig.…”
supporting
confidence: 72%
“…The trend to more positive ε Nd values in the Ghaggur through the Holocene does not reflect change in erosion patterns in the mountains themselves,which the delta records show to be the opposite of what is proposed in this study. Alizai et al (2011) interpreted single grain Pb isotope data from the Hakkra that parallels the Nd isotopes published by East et al (2015) to reflect evolution of a Himalayan fed stream being clogged by Thar Desert sand as the stream dried up . Such a change does not imply a major change of erosion in the source, as proposed by Singh et al (2016).…”
mentioning
confidence: 86%
“…The Ghaggar, on whose floodplains the drill sites of Singh et al (2016) sit, together with the Hakkra drill sites at Marot, Alkasur and Tilwalla (Alizai et al, 2011;East et al, 2015) (Fig. 2), is only draining the Sub-Himalayas, not the Lesser or the Higher Himalaya, so its not clear how changes in the relative flux from these ranges would have actually impacted the drilled location.…”
“…It is noteworthy that the reconstructed Ghaggar isotope trend of Singh et al (2016) is similar both in direction and timing, as well as depth, as that seen at Marot (Fig. 2), downstream of their drill sites (East et al, 2015), as well as at the much more distant section at Kanpur analyzed by Rahaman et al (2009), and which was already highlighted in their study. Indeed, if we plot the isotope character of the floodplains of the Hakkra River (downstream equivalent of the Ghaggar in modern Pakistan) near Marot we see that they form as single progressive trend, culminating in ε Nd values of -13 to -14 ( Fig.…”
supporting
confidence: 72%
“…The trend to more positive ε Nd values in the Ghaggur through the Holocene does not reflect change in erosion patterns in the mountains themselves,which the delta records show to be the opposite of what is proposed in this study. Alizai et al (2011) interpreted single grain Pb isotope data from the Hakkra that parallels the Nd isotopes published by East et al (2015) to reflect evolution of a Himalayan fed stream being clogged by Thar Desert sand as the stream dried up . Such a change does not imply a major change of erosion in the source, as proposed by Singh et al (2016).…”
mentioning
confidence: 86%
“…The Ghaggar, on whose floodplains the drill sites of Singh et al (2016) sit, together with the Hakkra drill sites at Marot, Alkasur and Tilwalla (Alizai et al, 2011;East et al, 2015) (Fig. 2), is only draining the Sub-Himalayas, not the Lesser or the Higher Himalaya, so its not clear how changes in the relative flux from these ranges would have actually impacted the drilled location.…”
“…4a). This young (<100 Ma) grain population is inferred to be derived by aeolian reworking of Indus plain sediments, which were transported by the northeastward winds blowing across the Thar Desert 66, 67 . The young peak cannot be explained as input from the Sutlej or Yamuna rivers, as apart from Miocene leucogranites, there are no sources of <100 Ma zircons east of Ladakh/Khohistan/Trans-Himalaya in Himalayan bedrock.…”
Urbanism in the Bronze-age Indus Civilisation (~4.6–3.9 thousand years before the present, ka) has been linked to water resources provided by large Himalayan river systems, although the largest concentrations of urban-scale Indus settlements are located far from extant Himalayan rivers. Here we analyse the sedimentary architecture, chronology and provenance of a major palaeochannel associated with many of these settlements. We show that the palaeochannel is a former course of the Sutlej River, the third largest of the present-day Himalayan rivers. Using optically stimulated luminescence dating of sand grains, we demonstrate that flow of the Sutlej in this course terminated considerably earlier than Indus occupation, with diversion to its present course complete shortly after ~8 ka. Indus urban settlements thus developed along an abandoned river valley rather than an active Himalayan river. Confinement of the Sutlej to its present incised course after ~8 ka likely reduced its propensity to re-route frequently thus enabling long-term stability for Indus settlements sited along the relict palaeochannel.
“…Sediments coming from the Thar Desert 25, 33 could also account for a significant contribution to GRK (Fig. 2), but this is not surprising as the Thar has been interpreted as a mixture of Himalayan and Sub-Himalayan sediments from the Indus and Ghaggar-Hakra systems 23 . However, Thar Desert is a vast sediment reservoir that is still poorly characterized geochemically.Figure 2Scatter plot of 87 Sr/ 86 Sr and ε Nd isotope compositions of our GRK sediments, Indus delta/floodplain (Clift et al .…”
The lost Saraswati River mentioned in the ancient Indian tradition is postulated to have flown independently of the Indus River into the Arabian Sea, perhaps along courses of now defunct rivers such as Ghaggar, Hakra and Nara. The persistence of such a river during the Harappan Bronze Age and the Iron Age Vedic period is strongly debated. We drilled in the Great Rann of Kachchh (Kutch), an infilled gulf of the Arabian Sea, which must have received input from the Saraswati, if active. Nd and Sr isotopic measurements suggest that a distinct source may have been present before 10 ka. Later in Holocene, under a drying climate, sediments from the Thar Desert probably choked the signature of an independent Saraswati-like river. Alternatively, without excluding a Saraswati-like secondary source, the Indus and the Thar were the dominant sources throughout the post-glacial history of the GRK. Indus-derived sediment accelerated the infilling of GRK after ~6 ka when the Indus delta started to grow. Until its complete infilling few centuries ago, freshwater input from the Indus, and perhaps from the Ghaggar-Hakra-Nara, probably sustained a productive marine environment as well as navigability toward old coastal Harappan and historic towns in the region.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
