Mining activity generates significant changes in the ecosystems in which it takes place, affecting the atmosphere and the surrounding aquatic and terrestrial systems, causing the destruction of landscapes, the loss of vegetation, and altering native environments. As it is an impact associated with increasing urbanization and population growth, the area occupied by quarries has increased worldwide. In the province of Buenos Aires, quarries are often abandoned without any remediation, leading to further deterioration of the ecosystem. This work aims to analyze quarrying activity’s spatiotemporal effect on the Pampean grassland in the Tandilia mountains (Buenos Aires province, Argentina). Based on Landsat 5, 7, and 8 satellite imagery, from 1996 to the present, and using QGIS software, we identified the location and extension of quarries, and we analyzed their evolution through time. Quarries currently occupy an area of 6428 ha, which was originally part of the Pampean grassland. The number of open quarries increased by 129%, from 69 in 1996 to 158 in 2022, and the area used for this activity increased by 172%, with a greater expansion being detected in the last ten years. These results conclude that this extractive activity represents a major threat to the Pampean grassland with the consequent loss of biodiversity and invasion of exotic plants capable of colonizing areas altered by human activity.