Geodiversity Index for identifying priority areas for geoheritage along the BR-174 route in Roraima, northern Brazil

Abstract

Geodiversity, as the abiotic variety of nature, provides the foundation for identifying geoheritage elements. Roraima, located within the Guiana Shield, exhibits high geodiversity but lacks regional-scale quantification studies. This study aimed to quantify geodiversity along the BR-174 corridor and identify priority areas for future geosite inventories. The geodiversity index method was applied using GIS, analyzing class richness of lithology, geomorphology, and pedology on a 15 × 15 km grid classified by the Jenks natural breaks method. Results revealed a heterogeneous distribution, with 37% of the area classified as "high" and "very high", concentrated in the central region (Caracaraí, Iracema, Mucajaí, Amajari). A total of 67% of previously cataloged geological interest points coincided with these areas. We conclude that the index is an effective tool for regional-scale geoheritage prospecting, and the sectors mapped as priority along the BR-174 represent targets for future investigations, supporting geoconservation policies and territorial planning.