Archive of September 22th, 2007

Teacher at Sea log for September 22, 2007

Yesterday afternoon I observed the robotics experts make the repairs that were needed on Jason 2's arm. They tested the electrical circuits with a meter and then ran the arm through its motions and tested all of its functions. Thursday they had to replace the thumb to get it to work. This morning they noticed that the current was warming up the spool and they added a fan to the cable room.
Think about what this machine is accomplishing. It is working more that two miles away from us and yet its response is nearly instantaneous, all the while being immersed in an extremely corrosive environment at tremendous pressure.

During today's dive the scientific staff saw an amazing animal, that they think might be a nudibranch. I posted a picture of it on the webpage. Yesterday the scientific staff saw some science rubbish: a hydrophone. The view from the video camera still mesmerizes me.

Science Update by Todd Bianco

Site 04 has presented a lot of manganese crust, mudstone, and conglomerates. This is not exactly the fresh lava flows we though we might find, but we continue to sample the outcrops of conglomerates and breccias because it is becoming clear that the nature of these rocks is important to the formation of the bathymetric "bump" south of Kauai. This is because we have also observed similar morphology at Site 02 and Site 03, which are the western and southern most points of the "bump," respectively. Similar morphology may indicate a linked history between the sites, and since the locations are very far apart, the event would have to be widespread.
Landslides can be such a widespread event, but at Hawaii, widespread mass wasting observed offshore is often associated with landslide features onshore, such as the flat sides of northeast Oahu and northern Molokai. No such landslide feature exists on the southern side of Kauai, meaning another widespread event, perhaps volcanism, formed the "bump" south of Kauai. It is possible, however, that a Kauai landslide formed early, and subsequent volcanism filled in the missing onshore lava. The composition and age of our samples will shed light on the different possibilities. Old, shield-like lava may support a landslide, while young, late-stage lava may support a volcanic origin.

Presented by the School of Ocean and Earth Science and Technology at the University of Hawaii, with financial support from the National Science Foundation.