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Core, Flag and SunriseSeptember 3, 2012

Good morning, today is 00.30 in the morning Chikyu time. The first September 2012. Time running so fast, it’s already our 36 days in the Chikyu. In this expedition I am assigned as sedimentologist. It’s always exciting for me to start my working shift and wondering what kind of core we will explore tonight. My shift starts from 00.00am in the morning until 12 noon time. Today, I have a very good sleep, feel fresh and ready to explore the core.

Originally I am from Indonesia but currently I am studying at University of Queensland Australia. It’s only 1-hour difference between Brisbane and the Chikyu, with Brisbane ahead. While in the beginning I need sometime to adjust my bioclock for the nightshift job, now I just feel it’s definitely fine. In fact, I feel lucky to be in the night shift as I have the opportunity to enjoy fresh air in the morning and of course sunset almost every day.

There are 3 sedimentologists working in each shift. Our group primary responsibility is to describe the lithology and stratigraphy of sediments and sedimentary rocks both in cores and cuttings as well as provide a written interpretation about the geologic history of the drilling site from the lithological perspective.

Other than working as shipboard scientist, we also pursue our own scientific interests and assist with other scientific duties in this project. For instance, my particular interest in this project is to compare the Indonesian, Australian and Japanese Tertiary coals bioavailabilty potential for the future natural gas regeneration.

Before the cores lying in our description table, actually they have quite a long journey. It need approximately 3-4 hour before they are ready to be analyzed in our table. In general, once they arrived on deck, the core will be cut every 1.5 meter, go for XCT scan, and then will be cut whole round for microbio and interstitial water samples.

After the completion of these whole-core analyses, the core sections (1.5 meter length) are carried into the core splitting room, where they are halved lengthwise by the lab technicians into 2 split cores, working half and archive half.

The archive half is the one that taken to sedimentology laboratory for visual description while the working half is taken to the sampling table, where the curatorial representative oversees the collection of samples for shipboard and shore-based scientists analyses. Our description table is equipped with 8 flat core racks about 2 meter long, meter sticks, and overhead track lights.

Our principal task of the shipboard sedimentologists is the layer-by-layer description of the sediments or sedimentary rocks within the cores. We will record our description on the Visual Core Description form. In our routine work, first we need to define layer on the basis of variations in its sediment lithology, color, sedimentary structures, or other specific characteristics.

After that, overall on each core we will observe: the thickness and attitude of sediment layers, structures, bedding planes, lithology, color and degree of disturbance by the drilling process. We also need to make smear slides or thin section and analyzed them under the microscope in order to do lithology checking.

In this expedition, sedimentologist is also helping the curator preparing all the requested samples both for shipboard or shore based analyses. As a sedimentologist, our world is full of flags. Flag for taking samples for shipboard analysis, flag after finish our visual description work or flag for taking personal samples.

Don't think these are as big flags, just tiny flags of printed paper glued into the toothpicks. I like to see many flags placed on the core sample cut in half, some of the flags with the nice picture of the people who requested the samples. It’s just so cool to have our own flag. I think I will bring home my own flag and will ask one of my colleague’s flag for memories as well.

After several hours work, we will have a nice sun rise break... usually we go to the helideck, enjoy the fresh morning air while watching the sunrise... it’s just a wonderful moment.

Later when I am going back to my routine life, something that I will always remember from this expedition is “core, flag and sunrise”... It’s definitely one of my delicious menus in the Chikyu life.

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