Central Caldera Site: The broadband seismometer  (OBSBBA301) and low-frequency hydrophone (HYDFA305) were deployed next to the medium-powered junction box MJ03F for later connection to the extension cable running from PN3B to this site. A good final installation site for the seismometer was marked with Marker 23. Video credit: NSF-OOI/UW/CSSF; Dive R1725; V14. (02:44)