Investigation of ground instability and sinkhole monitoring in Slănic Prahova, Romania with InSAR and in-situ measurements

Sinkholes represent a significant geohazard, especially in urban environments where their sudden formation damages infrastructure, property, and even loss of life. These features, often caused by natural processes such as the dissolution of soluble rocks (e.g., limestone, gypsum) or human-induced activities like water extraction and construction, pose unique challenges in urban areas.

In April 2024, Slănic Prahova, Romania, experienced a significant geological event. Near the local police headquarters, a portion of 23 August Street collapsed, creating a crater approximately 2 meters deep and over 60 square meters. Due to safety concerns, around 42 residents were evacuated from nearby buildings.

Following the event, several campaigns were started to monitor and assess the ground deformations of the sinkhole and its surroundings. This event underscores the importance of continuously monitoring and assessing natural hazards in urban areas, particularly in regions with known subsurface vulnerabilities.