Dredge 22 - mantle peridotite- but with some fresh pieces…
Sentry was launched in the “wee” hours of the morning and was recovered this evening in order to avoid worsening weather over night. We are excitedly waiting to see the map it collected across the transfer zone between the normal and oblique ridge segments.
Whilst Sentry was mapping, we carried out two more dredges near the transfer zone. Dredge 19 on an adjacent ridge recovered more peridotite, including some interesting plagioclase infused mylonites and some dunites. Dredge 20 deep into the floor of the valley recovered no rocks.
Today we continued our multi beam surveying and described and processed the three peridotite dredges from yesterday. At 6pm, we dredged a large, 3000m high, mountain (rises up to 500 metres below sea level) in the north of our area. The hunch was that it might be a large basalt volcano, but no!, once again massive peridotite; with a bioclastic carbonate cap. And the question of the day quickly became, “How do we raise a mountain of peridotite to near sea level?”