20.03.2010  
     
 
Groundhog Day by Colin Graham
Week 3 - Expedition Log for IODP Expedition 325
 
  Hello. My name is Colin. My home, for now, is on the Great Ship Maya. My postal address is Bottom Bunk, Cabin 21, Boat Deck (starboard side), Great Ship Maya, Coral Sea – east of
Queensland, Australia. I am one of the more than sixty people that live and work together onboard. OK – ‘work’ is perhaps not the right word in my case, but I like to think that I do useful stuff anyway.

Life on board is lived vertically. There are 10 decks on the Maya. Starting at the bottom of the ship: Tank Top, Tween Deck, Main Deck, Shelter Deck, Mezzanine Deck, Forecastle Deck, Boat Deck, Captain’s Deck, Bridge Deck and Top of Wheelhouse – got all that? My life revolves around the Boat Deck (home), Forecastle Deck (laundry), Shelter Deck (food), Main Deck (gym, changing and work) and Mezzanine Deck (the drill floor).

G_Lott@ECORD_IODP: View of the Mezzanine level drilling deck with ESO containers.

My ‘day’ starts early at about 10pm when I get woken up by my cabin mate, Dave (the electronics engineer), coming to bed after his shift. I am lying in my bottom bunk, with curtains closed across the entrance to the bunk, and am nice and cosy, and now, part way between waking and sleeping. Dave has the bunk above me. He is fairly well house-trained, so is good to share a small cabin with. I hope he says the same about me. It is not quite time to get up yet, so I enjoy being able to turn over and ‘snooze’ for another hour or so.

Suddenly the alarm is sounding loud in my ear at 11pm. I’ve fallen back into a deep sleep. I fumble to find the alarm to switch it off. The next few minutes are critical. If I do not open my eyes and sit up, I will fall back asleep. I consider this very tempting alternative for a few moments, groan (quietly), then open the curtains and haul myself out of the warm bunk, reluctantly. I do not want to disturb Dave, so I give my face a ‘cat’s-lick’ of a wash, put on my
T-shirt, shorts and floppy sandals and slip quietly (I hope) out the cabin with eyes half shut against the glare of the bright lights of the Boat-Deck corridor.

I stumble along to the stairway with my eyes adjusting to the light, then go down two decks to the Shelter Deck for breakfast in the mess, and to meet up with my workmates starting work at midnight. After eating, and feeling a bit more awake (but sometimes not), I go down another level to the Main Deck to change into working clothes in the locker room. Off with the T-shirt, on with the overalls, safety boots and hard hat. Check that I still have time to grab a
tea in a paper cup. I’m ready to face the world.

I go outside, holding my paper cup, which is by now burning my fingers, and feel the heat and humidity of the outside air, and sometimes the wet of the rain or sea spray. I sway as I adjust to the heave and rolling motion of the ship, trying not to spill my tea. I zig-zag as I make my way to the aft end of the main deck along the route between the assorted diesel generators,compressors and pumps, that power the drill floor above on the mezzanine deck, and the
associated containers, winches, metal supports and endless pipework. This home-to-work commute lasts about 1 minute and is the longest horizontal walk I make on the ship. As I pass by, the noise of the machinery is deafening, and the heat given off is tremendous, like passing by a row of hot air blowers.

M_Mowat@ECORD_IODP: The commute!

I reach my work container in the relative quiet at the stern of the ship, feeling the vibration of the stern thrusters coming through my boots. I pull hard to open the metal door against the resistance of the rubber seals that keep water out and the cool air-conditioned atmosphere
inside. Sometimes it takes two or three yanks at the door, in my weakened, early-morning state, before it opens. Inside, Mary – my colleague on the opposite shift – is waiting for me to appear. She greets me with a smile. Is it because of the way I look first thing in the morning
(that stunned, still half-asleep, dragged backwards through a hedge look), or because it is the end of her shift (so she can go and eat, relax and sleep for the next twelve hours)? Perhaps it’s a bit of both. Working on opposite shifts, I say “good morning” while Mary says “good
evening”.

D_Wallis@ECORD_IODP: ‘The Office’- Colin hard at work in the database container.

I get an update of what has happened in the past twelve hours, any problems, any fixes, anything outstanding that I need to work on. I’m ready. Mary says “good night”, and then
shoulders the door to open it against the resistance of the rubber seals. The door slams shut and I’m on my own, with my cup of tea cool enough to drink. I start to look at the computer screens and at the data and the systems information, turn on some music and focus on the
work.

Five minutes before mid-day, there are a couple of tugs on the container door. It opens and Mary enters. I have a smile on my face. We have the good morning – good evening exchange in reverse. After the handover, I say “good night”, shoulder the door to open it and make the zig-zag commute back to the accommodation. Something to eat, visit to the gym, shower, climb into my bunk, shut the curtains, read for a bit, fall asleep.

My ‘day’ starts early at about 10pm when I get woken up by my cabin mate, Dave (the electronics engineer), coming to bed after his shift……….

This ‘groundhog day’ pattern of life repeats 7 days a week, for weeks on end. Everybody on the ship – the ship’s crew, the drillers, the ESO staff and the scientists have their own workrest patterns in each 24-hour period, and workmates on the opposite shift (or watch in the case of the ship’s crew). Although we all work and live in a small space, you are not aware that there are over sixty people onboard. There are people you never see (except during fire and boat drills) because they are on different shifts, eat at different times, and have different commutes to and from their work places, and different jobs.

……….Suddenly the alarm is sounding loud in my ear at 11pm. I’ve fallen back into a deep sleep. I fumble to find the alarm to switch it off. The next few minutes are critical. If I do not open my eyes and sit up, I will fall back asleep. I consider this very tempting alternative for a
few moments, groan (quietly), then open the curtains and haul myself out of the warm bunk, reluctantly.

Author: Colin Graham
 
 
 
Wissenschaftsredaktion 20.03.2010, 09:45 # 0 Kommentare
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  20.03.2010  
     
 
Expedition Log for IODP Expedition 325
Great Barrier Reef Environmental Changes
 
  A Science Aside by Carol Cotterill

On February 27th at 16:34 Brisbane time (+10 hours GMT), there was a devastating earthquake in Chile, Magnitude 8.8. This was followed by multiple aftershocks, some of which were larger in themselves than the Haiti quake. An unusual start to a logbook entry from the Great Barrier Reef you may think – how can those events on the other side of the Pacific relate to our activity?

Initially our interest was piqued, as family and friends began to log onto facebook and other such networking sites discussing the impact of the earthquake. This soon turned into monitoring of the effects, as both NOAA and the Joint Australian Tsunami Warning Centre issued Pacific wide tsunami alerts – would it reach us here? Would we feel the effects or would the wave be dissipated? If it did reach here, how large would it be and when would it arrive?

TSUNAMI BULLETIN NUMBER 005
PACIFIC TSUNAMI WARNING CENTER/NOAA/NWS
ISSUED AT 1045Z 27 FEB 2010
THIS BULLETIN APPLIES TO AREAS WITHIN AND BORDERING THE PACIFIC
OCEAN AND ADJACENT SEAS...EXCEPT ALASKA...BRITISH
COLUMBIA...WASHINGTON...OREGON AND CALIFORNIA.
... A WIDESPREAD TSUNAMI WARNING IS IN EFFECT ...
A TSUNAMI WARNING IS IN EFFECT FOR
CHILE / PERU / ECUADOR / COLOMBIA / ANTARCTICA / PANAMA / COSTA
RICA / NICARAGUA / PITCAIRN / HONDURAS / EL SALVADOR / GUATEMALA /
FR. POLYNESIA / MEXICO / COOK ISLANDS / KIRIBATI /
KERMADEC IS / NIUE / NEW ZEALAND / TONGA / AMERICAN SAMOA / SAMOA /
JARVIS IS. / WALLIS-FUTUNA / TOKELAU / FIJI / AUSTRALIA / HAWAII /
PALMYRA IS. / TUVALU / VANUATU / HOWLAND-BAKER / NEW CALEDONIA /
JOHNSTON IS. / SOLOMON IS. / NAURU / MARSHALL IS. / MIDWAY IS. /
KOSRAE / PAPUA NEW GUINEA /
POHNPEI / WAKE IS. / CHUUK / RUSSIA / MARCUS IS. / INDONESIA / N.
MARIANAS / GUAM / YAP / BELAU / JAPAN / PHILIPPINES / CHINESE TAIPEI
THIS BULLETIN IS ISSUED AS ADVICE TO GOVERNMENT AGENCIES. ONLY
NATIONAL AND LOCAL GOVERNMENT AGENCIES HAVE THE AUTHORITY TO
MAKE DECISIONS REGARDING THE OFFICIAL STATE OF ALERT IN THEIR
AREA AND ANY ACTIONS TO BE TAKEN IN RESPONSE.
AN EARTHQUAKE HAS OCCURRED WITH THESE PRELIMINARY
PARAMETERS
ORIGIN TIME - 0634Z 27 FEB 2010
COORDINATES - 36.1 SOUTH 72.6 WEST
DEPTH - 55 KM
LOCATION - NEAR COAST OF CENTRAL CHILE
MAGNITUDE - 8.8
MEASUREMENTS OR REPORTS OF TSUNAMI WAVE ACTIVITY
GAUGE LOCATION LAT LON TIME AMPL PER
------------------- ----- ------ ----- --------------- -----
IQUIQUE CL 20.2S 70.1W 0906Z 0.27M / 0.9FT 72MIN
ANTOFAGASTA CL 23.2S 70.4W 0941Z 0.49M / 1.6FT 52MIN
ARICA CL 18.5S 70.3W 1007Z 0.94M / 3.1FT 44MIN
DART LIMA 32412 18.0S 86.4W 0941Z 0.24M / 0.8FT 36MIN
CALDERA CL 27.1S 70.8W 0843Z 0.45M / 1.5FT 20MIN
TALCAHUANO CL 36.7S 73.4W 0653Z 2.34M / 7.7FT 88MIN
COQUIMBO CL 30.0S 71.3W 0852Z 1.32M / 4.3FT 30MIN
CORRAL CL 39.9S 73.4W 0739Z 0.90M / 2.9FT 16MIN
SAN FELIX CL 26.3S 80.1W 0815Z 0.53M / 1.7FT 08MIN
VALPARAISO CL 33.0S 71.6W 0708Z 1.29M / 4.2FT 20MIN

It is known that tsunamis generated from earthquakes or submarine slides can travel at the speed of passenger jets, at up to 950km per hour, with wavelengths up to hundreds of kilometres in length. However, despite these statistics, in the open ocean the wave is often only around 1m in height and so it can be easily missed in the background sea swell!

Initially the maps showed that we were working in an area that would be effect free, with the main marine warning limited to coastline from Sydney to Brisbane. But by 7am on the 28th, this marine warning area had crept slowly northward, until it was not far away from our coring location. So now the discussions began as to the best
tactics.....should we continue coring or pull the pipe in case of a wave that took us beyond our 2.5m heave capacity? Would its arrival coincide with a high tide, which due to being on Springs, would compound the height and heave problem caused by the sea swell? Would the main effect actually be felt not from the incoming wave, but
from any return waves / currents channelling back out through the reef passages afterwards? Should we contemplate doing our usual CTD dips to measure the physical structure of the water column if tides and currents were going to be unusual and increased in strength?

By 08.15 am, any tsunami effects were due to have reached the area around Brisbane. Logging on to the regular updates, we could see that the waves reaching the coast were minimal – in the order of 10-15cm above the usual tidal heights. And so the next question.......would we even notice it at all?! NOAA had its arrival at Mackay down for 12:51 local time......and so we waited!

The sun beat down on the boat deck as we all assembled for a fire drill at 12:50.....and then all left at 13:00 with not so much as a ripple over the usual sea swell. But yesterday (March 1st) Martin Kölling, one of the geochemists onboard, came and showed me an interesting plot.



On his laptop he has a piece of software installed called “SeisMac”. This monitors the movement of the laptop in the x, y and z orientation. He printed out a plot for a 15
minute period which appears to show an increase in the average sea swell induced fluctuations of the drill floor of approximately 0.5g for a period of 1.5 minutes,
occurring between 18 and 19 hours after the initiation of the tsunami in Chile. When we checked against the predicted arrival time plot generated by NOAA, it matched this time window.



So, as an aside to coring for past records of sea level change on the Great Barrier Reef had we actually managed to record a present day sea level change event? The jury is still open….but I’m pretty convinced!

Author: Carol Cotterill
 
 
 
Wissenschaftsredaktion 20.03.2010, 09:27 # 0 Kommentare
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