Abstract
Approximately 140 million years ago, the Indian plate separated from Gondwana and migrated by almost 90° latitude to its current location, forming the Himalayan-Tibetan system. Large discrepancies exist in the rate of migration of Indian plate during Phanerozoic. Here we describe a new approach to paleo-latitudinal reconstruction based on simultaneous determination of carbonate formation temperature and δ18O of soil carbonates, constrained by the abundances of 13C-18O bonds in palaeosol carbonates. Assuming that the palaeosol carbonates have a strong relationship with the composition of the meteoric water, δ18O carbonate of palaeosol can constrain paleo-latitudinal position. Weighted mean annual rainfall δ18O water values measured at several stations across the southern latitudes are used to derive a polynomial equation: δ18Ow = −0.006 × (LAT)2 − 0.294 × (LAT) − 5.29 which is used for latitudinal reconstruction. We use this approach to show the northward migration of the Indian plate from 46.8 ± 5.8°S during the Permian (269 M.y.) to 30 ± 11°S during the Triassic (248 M.y.), 14.7 ± 8.7°S during the early Cretaceous (135 M.y.), and 28 ± 8.8°S during the late Cretaceous (68 M.y.). Soil carbonate δ18O provides an alternative method for tracing the latitudinal position of Indian plate in the past and the estimates are consistent with the paleo-magnetic records which document the position of Indian plate prior to 135 ± 3 M.y.
Highlights
140 million years ago, the Indian plate separated from Gondwana and migrated by almost 90° latitude to its current location, forming the Himalayan-Tibetan system
Sedimentary sequences comprised of packets of soil carbonate were deposited along the palaeo channel of the present day Narmada River while the Indian plate drifted from its position in the Southern Hemisphere[8,9]
The isotopes in precipitation show very good agreement with the simulated meridional distribution. Does this validate using soil water δ 18O as a paleo-latitudinal proxy, it implies that the global-scale hydrological cycle was not fundamentally different during the climates of the late Paleozoic and Mesozoic
Summary
Prosenjit Ghosh[1,2], Mikhail V. The strongest evidence comes from the reconstruction of linear magnetic anomalies recovered from sub-aerial flood basalts deposited on continental-rift and sedimentary packets, which preserve information about the paleo-magnetic pole together with the occurrence of climate-sensitive litho-units like coals, evaporates, bauxites and tillites in the sedimentary successions[1,2,3,4] These paleo-magnetic records disagree in the paleo-position of India during the late Paleozoic and Mesozoic time by up to 30 ̊ latitude. Sedimentary sequences comprised of packets of soil carbonate were deposited along the palaeo channel of the present day Narmada River while the Indian plate drifted from its position in the Southern Hemisphere[8,9] These carbonates capture the isotopic signature of ancient soil water, which resemble the isotopic composition of meteoric water. The overlying sequence of Deccan basalt restricted water-rock interaction creating an environment for excellent preservation of these soil archives[8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
