Tracing Uplift of the Northern Andes using Luminescence Sensitivity in Quartz

• Grant number: 22/16709-8
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): March 01, 2023
• Status: Discontinued
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Mauricio Parra Amézquita
• Grantee: Carlos Andrés Ortiz Barrios
• Host Institution: Instituto de Geociências (IGC). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 18/15613-1 - Topographic construction along the northeastern Andes and the origin of the Transcontinental Amazon Basin, AP.JP2
• Associated scholarship(s): 23/07536-5 - Tracing Uplift of the Northern Andes using Luminescence Sensitivity in Quartz, BE.EP.MS

Abstract

Provenance analysis allows the detection of erosional windows in active orogens by tracking sediment populations in their adjacent basins, providing useful information to track orogenic uplift and exhumation. One prominent example is found in the northern Andes, where rock uplift formed the current amazon basin headwaters. In recent years luminescence sensitivity has arisen as a potential technique for provenance analysis. Especially, the optically stimulated luminescence (OSL) and thermoluminescence (TL) sensitivities in quartz. These properties are modified by irradiation-exposure cycles which occur normally in soil profiles, linking sensitivity with source area denudation rates, sedimentary reworking, and recycling. Luminescence sensitivity has been successfully used to discriminate sediments and for provenance analysis in modern deposits, on the other hand, it has been hardly tested in ancient ones. Here, we characterize an entire exhumed crustal section of the Colombian Eastern Cordillera and one adjacent basin, with a well-known provenance history, in terms of luminescence sensitivity, spanning rocks from the whole Phanerozoic eon. This approach allows us a direct source-to-sink analysis which serves as a proof-of-concepts of the applicability of the luminescence sensitivity as a provenance tool, additionally attempting to track orogenic uplift, changes in source area denudation rates, and sedimentary recycling. We compare the luminescence sensitivity results with quartz sandstone petrographic analysis in order to link changes in sensitivities with quartz origin and sedimentary history and refine previous provenance data for a better understanding of the Andean construction.