Introduction

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R/V Pelagia Cruise GLOW
	Diary overview
Sunday, 22 February
Box and piston coring Davie Ridge! Tremendous excitement on board the Pelagia, cores came on deck for the last two days. Everybody worked hard to make this event successful, making long working days. The sediments turn out to be extremely clay rich in this area, which has its positive and negative sides. The positive side is that the carbonate bearing fossils are extremely well preserved, even in samples from 6-7 million years old. The clay helps to preserve the foraminifers. The negative side is that the high clay content makes piston coring difficult. So far the longest recovery is 4.5 meters. The box cores are great, no problem whatsoever. The canyon sample on northern Davie Ridge revealed a very recent infill of turbiditic sand. Recent and Pleistocene sediments form a cover, like a blanket, across Davie Ridge Often the box cores retrieved just sediments from this drape, or where there has been no recent deposition, old outcropping sediments. Despite this we managed to date Miocene and Pliocene outcropping sediments from the canyon walls to tie to the seismic lines. We sampled also sediments from the Sea Gap area. A similar story, we were confronted with the battle to punch through the Pleistocene sediments. Here there was not much luck, but in one location again upper Miocene sediments were collected. There is a large group of micropaleontologists on board to date the sediments immediately upon retrieval. It is quite amazing how these tiny fossils become so important for the success of the cruise. The micropaleontologists are amazed by the pristine shells: cries of 'wonderful, gorgeous, and awesome' are often heard from the wet lab.   The Miocene sediments are really prominent in the area, and form the lower cliff faces of the Davie Ridge and the Sea Gap areas. These sediments tell a remarkable story of uplift of East Africa and climate change. Also Davie Ridge and the Sea Gap experienced rapid uplift after deposition of the upper Miocene sediments, and hence the large canyons on top. Several scientists are frantically working together on the seismic lines to put the geological story together, of rotating plates, mountain formation, and deep sea canyons, fascinating stuff. So far we are really enjoying this. Now we have explored the eastern part of the GLOW area, we are back to once again shooting a beautiful seismic line, sailing slowly towards the coast. We hope to find other areas where older sediments might be outcropping. Departure from Davie Ridge was not a final exit from this area, we shall return to make crossing seismic lines for future drilling locations. The shipboard party