Paleowave

A Day in the Life

Looking outside the sedimentologists' window. This was on a particularly rocky day!

Looking outside the sedimentologists' window. This was on a particularly rocky day!

I could really do with some fresh cow's milk...

I could really do with some fresh cow's milk...

  • 09:45 – Alarm rings; Hit snooze.
  • 10:00 – Slowly climb down from bunk bed.
  • 10:10 – Brush/shower/shave. Leave laundry bag outside.
  • 10:30 – Breakfast: All bran cereal and Gossner Whole Milk. Grab a quick cup of Ahmed Tea (‘England’s Finest’)
  • 11:00 – Head to the core lab for a quick update from the night-shift sedimentologists.
  • 11:30 – Catch some sunlight outside.
  • 11:45 – ‘Official’ crossover meeting with the night-shift scientists.
  • 12:00 – Shift begins; Start describing mud.
  • 12:15 – Periodically bug our smear-slide person for lithology estimates.
  • 12:45 – Annoy the biostratigraphers about the latest age estimate.
  • 13:00 – Enter descriptions into database software DESCLogik.
  • 13:05 – DESCLogik woes.
  • 13:10 – DESCLogik works!
  • 13:15 – DESCLogik hangs.
  • 13:20 – Gripe about DESCLogik-induced rollercoaster of emotions.
  • 13:30 – Resume logging mud on tracks and describe sediments.
  • 14:00 – Another cup of tea.
  • 14:10 – More mud!! And interesting sediments!
  • 14:30 – “Oh look, a nodule!”
  • 15:00 – Down to the Galley for a cookie break. And yet another cup of tea.
  • 15:30 – Make a decision about music preferences for the afternoon.
  • 16:00 - Annoy the biostratigraphers. For ages and for amusement.
  • 16:30 – “Core on deck!” More DESCLogik fun.
  • 16:45 – Joke around with paleomagnetism and physical properties’ scientists. Also get updates/data.
  • 17:00 – Lunchtime: Vegetarian meal of the day and Pocari Sweat for refreshment.
  • 17:30 – Back to the mud!
  • 18:00 – More aggressive music to avert drowsiness.
  • 18:30 – Go outside on the bridge deck to catch the sunset.
A gorgeous sunset in the Mahanadi Basin.

A gorgeous sunset in the Mahanadi Basin.

  • 18:31 – Gawk at the sunset and the ocean and congratulate yourself on choice of profession.
  • 18:45 – Reluctantly go back inside.
  • 18:46 – More cores? Wow.
  • 19:00 – DESCLogik apathy.
  • 20:00 – Try not to look at the clock.
  • 21:00 – Last cup of tea and cookie break.
  • 21:30 – Frantic DESCLogik cleanup prior to crossover.
  • 22:00 – More mud…
  • 22:30 – Gather thoughts and data for crossover meeting.
  • 22:45 – “Oh look an anomaly!”
  • 23:00 – “That’s really interesting!”
  • 23:30 – Head down to Galley to order and store a meal.
  • 23:45 – ‘Official’ crossover meeting with the night-shift scientists. Our turn to present this time.
  • 00:00 – Satisfied with the amount of science for the day.
  • 00:10 – Get off shift! Yay!
  • 00:11 – Run down to the room to throw on some gym clothes.
  • 00:14 – Head to the movie room for “INSANITY” workout session.
  • 00:50 – Regain self-respect and composure after workout.
  • 01:30 – Dinner: Beans, rice, boiled vegetables, and one boiled egg with pepper. More Pocari Sweat.
  • 02:00 – Actual free time! (Catch a movie/show, depending on level of fatigue)
  • 02:45 – Sleep!

iMonsoon: Life of a Sedimentologist

The main job of the JOIDES Resolution (or JR for short) is to drill beneath the seafloor and to collect intact sediment cores. Once it gets started, the JR does a really, really efficient job of retrieving core. Every fifteen minutes or so (depending on the water depth at a location, the type of drill bit used, and the characteristics of the material being drilled), one can hear ‘Core on Deck!’ This chant is frequent enough to develop a Pavlov-like reflex.

‘Core flow’ is a JR term to describe the journey of a piece of mud from its inception at the drill rig to its resting place in a U-tube in the basement refrigerator. The scientists at the foremost part of the core flow are those in charge of measuring physical properties on the whole-round core (imagine a clear, plastic cylinder filled with sediments and rocks).

Next, the technicians onboard (who brought out the core from the drill rig via the ‘catwalk’ in the first place) proceed to split the whole-round core into two halves: the working half and the archive half. Many scientists now descend upon the working half, carefully sampling the mud for various chemical and physical measurements. It’s quite a spectacle – especially when we’ve hit a transition or a well-known boundary! What about the archive half? Well, this is where the sedimentologists come into the picture.

The main job of the sedimentologists (8 of us in total on this expedition, with one soon to join) is to describe, characterize, and make detailed reports about the contents of the mud. We are also responsible for walking the archive halves through the SHIL and SHMSL: two fancy imaging instruments that can take high-resolution photographs, and make color-based and magnetic susceptibility measurements which become important for the stratigraphic correlators onboard.

Once these scans are finished, the fun begins. Using tried and tested, yet basic, tools (see picture) we try and characterize the makeup of the mud. We document the colors using Munsell charts, note the texture of the sediments using the spatula, and then try and see interesting features using our hand-lens. It is also our job to document how the drilling process might have disturbed the recovered cores. Another vital aspect of the description process is making smear slides, where a small amount of sediment is taken on a glass slide for observation under a powerful microscope. This can be really handy for distinguishing the amounts of clay, silt, sand, and even identifying minerals or volcanic ash!

After the first five cores or so, all of us sedimentologists (4 in the day shift) became cogs of a bigger, well-oiled machine. Mind you, there were ~50 cores in the first hole, each composed of 4-7 1.5 m sections (!) – so we see a LOT of core, and during most parts, it can be run-of-the-mill. However, when something exciting does pop up (which can happen quite frequently at times), we usually all gather around the description table, huddle together, take notes and photographs, and have lively conversations and debates, and ultimately marvel at how we can catch glimpses of a world that was millions of years younger…

iMonsoon

Ahoy! I am typing this blogpost aboard the JOIDES Resolution, the flagship of the International Ocean Discovery Program, in the middle of the Indian Ocean! Last night, we reached Ninetyeast Ridge (most-creatively named!), the first drilling site of our research expedition. Currently we are waiting for the drillers to make sure all the equipment is calibrated and ready-to-go. All of us on the day shift and a few from the night shift who are awake are excited and eager to see the first cores come up on deck.

The main goal of Expedition 353: Indian Monsoon Rainfall (or iMonsoon for short) is to understand how the Indian monsoon evolved over the last several tens of millions of years. How is this achieved? By retrieving land-based sediments that made their way to the seafloor through the numerous rivers that flow into Bay of Bengal and/or through wind-based transport. These sediments house the shells of oceanic critters that were living in the past (like foraminifera, diatoms, radiolarians etc.) One of the major factors that influences the chemistry of these sediments and the numerous fossils that are preserved in them is rainfall over the Indian Subcontinent.

So, these sediments hold the key to understanding past monsoon strength (or lack of it). The deeper we drill – the older the sediments. Why do we care about monsoons in the past? Well, we only have very brief instrumental measurements of how much it rained over India, perhaps, 100 years or so – a geological instant. The Indian monsoon has been around a lot longer than that and thus, to fully understand how the monsoon is capable of changing, we need to be really knowledgeable about its past.

The JOIDES Resolution is a very capable research vessel. There are 30 shipboard scientists aboard, each with a unique job assignment. In total, including the technical staff, drilling staff, and the crew, I think we are about ~100 people on the ship. The food is fantastic (lots of options), and the ship is equipped with a gym and movie room.

I am sailing as a sedimentologist on this expedition, which means I will be inspecting, characterizing, and describing all the cores that we collect. As I mentioned, we are eager to start seeing cores and getting a glimpse of what we will be working for the coming few years! I will try and update this spot periodically with our progress. Wish us luck!