Assertion: archipelago's island | /r/HasProperty | formed through volcanic and seismic activity
Facets:
value: during the neogene period
type: TEMPORAL
Source sentences:
text: The islands of the archipelago were formed through volcanic and seismic activity during the Neogene Period; the first embryonic surfaces started to appear in the waters of Santa Maria during the Miocene epoch (from circa 8 million years ago).