Reply to Comment on “Singh R, Vadlamani R, Bajpai S & Maurya AS (2024) Strontium Isotope Stratigraphy of Marine Oligocene–Miocene Sedimentary Successions of Kutch Basin, Western India. Geological Journal, 1–20. DOI: 10.1002/gj.4961”

Abstract

This response addresses the comments made by Saraswati et al. on our recent publication in Geological Journal. In our study, we used a multi-analytical screening approach, including visual, XRD and trace element analysis, to evaluate diagenetic alteration of carbonate shell samples. Contrary to the claims made by Saraswati et al. our findings are based on well-preserved samples with minimal alteration. The Sr-isotope data from the Khari Nadi Formation (23.07–18.09 Ma) are largely consistent with existing biostratigraphic constraints, but suggest a possible extension of the upper age limit into the Burdigalian. Our Sr-isotope ages for the Chhasra Formation (15.11–12.29 Ma) are younger than those suggested previously, based on larger benthic foraminifers, but largely corroborate recent nannoplankton data. As a result of the new age data from Kutch, we suggest that the sedimentation rates, derived from multiple samples, increased significantly from the Oligocene to Miocene. We assert that ‘established’ ages are also subject to refinements as the rock units become amenable to new dating techniques. We welcome any criticism that is constructive, and remain open to any further data that could refine or challenge our interpretations.