Data and supplementary information for - Long term evolution of an escarpment in a tableland landscape (Serra Geral de Goiás, Brazil): insights from in situ-produced cosmogenic nuclides

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These text and Excel files provide supplementary information for the paper entitled "Long term evolution of an escarpment in a tableland landscape (Serra Geral de Goiás, Brazil): insights from in situ-produced cosmogenic nuclides". The objective of this dataset is to present all the analytical results that support all the conclusions included in this paper.

Among the diversity of geomorphic systems, topographic escarpments are salient relief features besides mountain belts. This study presents a new dataset focused on the Serra Geral Escarpment in Goiás State, one of the most significant and longest geomorphic features in Central Brazil.
Using in situ-produced cosmogenic nuclides (10Be, 26Al, and 36Cl) concentrations measured in river-borne sediments and bedrock samples, it reveals distinct denudation rates for the main geomorphic compartments of the Serra Geral region. The Western Bahia Plateau exhibits a denudation rate of 3±2 to 9±1 m Myr-1, the Paranã Gap, along the toe of the escarpment, exhibits a rate of 25±1 m Myr-1, and the escarpment shows a rate of 144±40 m Myr-1. The isotopic dataset suggests a complex cosmogenic 26Al/10Be signature, potentially resulting from deep-seated mass wasting in the central section of the escarpment, cave ceiling collapses in the Vão do Paranã, as well as vertical mixing within the thick regolith covering the sandstones capping the Western Bahia Plateau. Preliminary constraints indicate a minimum differential denudation of the relief around 14-24 m Myr-1, an escarpment horizontal retreat rate of 119±21 m Myr-1, and an initiation of pediplanation, resulting to the Patamares at the base of the escarpment during the Upper-Middle Miocene, approximately 8 to 18 million years ago.
These findings contribute to a better understanding of the geomorphic evolution of topographic escarpment in tablelands and cuesta landscapes. They also raise questions about the impact of karst formations, landslides, and regolith cover on the cosmogenic signal in low denudation settings such as Central Brazil.

• S1 – Excel file containing 5 spreadsheets with tables
• S1.1 – Geomorphic characteristics of the watersheds and localization of the samples
• S1.2 - Results of Accelerator Mass Spectrometry for in situ Be-10 and Al-26 (ASTER, LN2C, Aix-en-Provence, France)
• S1.3 - In situ production parameters, [Be-10] derived denudation rates and integration times, [Al-26] derived denudation rates
• S1.4 - Chemical analyses for 36Cl measurement (LF13)
• S1.5 - Chlorine-36 exposure age and erosion rate determination (after Schimmelpfennig et al. 2018)
• S2 – Text file dealing with supplementary information related to using cosmogenic nuclides (in situ-produced 10Be, 26Al and 36Cl)