Scientists have studied northeastern Italy’s Montello hill, located at the southern edge of the Alps, since the late 1800s. Despite consistent research, its relationship with neighboring tectonic structures remains hotly debated.
The region hosts dense population centers and significant economic activity. For example, it’s home to prosecco, a sparkling wine whose grapes are grown on the region’s mountain slopes. Understanding the tectonic activity in the region is therefore critical for the population’s safety, livelihood, and well-being.
In a new study, Picotti et al. discovered that Montello’s seismically active thrust region is larger and older than previously estimated, stretching almost to the city of Treviso. They found that Montello’s thrust region is shortening at a rate of 0.3–0.4 millimeter per year, whereas the nearby Bassano-Valdobbiadene thrust has an annual shortening rate of 1.4–1.7 millimeters per year. Although many regions of the Alps are considered tectonically dead, the authors conclude that the Southern Alps are, indeed, active.
The team reached this conclusion by integrating data from wells and reservoirs, seismic data from industry scientists, field observations, and microseismic measurements.
The findings are congruent with recent geological activity: The Montello region has experienced only one significant earthquake in recorded history (in 778 CE) and has generally been considered seismically quiet. Still, the authors warn that both the Montello and the Bassano-Valdobbiadene thrusts are active regions interlocked in a complex geological dance. Their seismic potential could be high, and this risk warrants future research to better evaluate hazards in the region. (Tectonics, https://doi.org/10.1029/2022TC007522, 2022)
—Morgan Rehnberg, Science Writer