
INGV (Italy's National Institute for Geophysics and Vulcanology) researchers make monthly measurements near the Bocca Grande in Pozzuoli, Italy on July 09, 2017.

INGV (Italy's National Institute for Geophysics and Vulcanology) researchers make monthly measurements near the Bocca Grande in Pozzuoli, Italy on July 09, 2017.

INGV (Italy's National Institute for Geophysics and Vulcanology) researchers make monthly measurements near the Bocca Grande in Pozzuoli, Italy on July 09, 2017.

INGV (Italy's National Institute for Geophysics and Vulcanology) researchers make monthly measurements near the Bocca Grande in Pozzuoli, Italy on July 09, 2017.

INGV (Italy's National Institute for Geophysics and Vulcanology) researchers make monthly measurements near the Bocca Grande in Pozzuoli, Italy on July 09, 2017.

INGV (Italy's National Institute for Geophysics and Vulcanology) researchers make monthly measurements near the Bocca Grande in Pozzuoli, Italy on July 09, 2017.

INGV (Italy's National Institute for Geophysics and Vulcanology) researchers make monthly measurements near the Bocca Grande in Pozzuoli, Italy on July 09, 2017.

INGV (Italy's National Institute for Geophysics and Vulcanology) researchers make monthly measurements near the Bocca Grande in Pozzuoli, Italy on July 09, 2017.

INGV (Italy's National Institute for Geophysics and Vulcanology) researchers make monthly measurements near the Bocca Grande in Pozzuoli, Italy on July 09, 2017.

INGV (Italy's National Institute for Geophysics and Vulcanology) researchers make monthly measurements near the Bocca Grande in Pozzuoli, Italy on July 09, 2017.