The wonderful world of pore water!

Why would anyone care about the water inside sediment at the bottom of the ocean? Well, I am glad you asked! Ocean sediment records the Earth’s climate history. Like reading a book backwards, the deeper you drill into ocean sediment the farther back in time you go. This is because small matter (scientists call them particulates) falls inside ocean water, and over time, accumulates on the seafloor. These particles can be many different things, such as stuff coming off land inside rivers, the bodies of tiny sea creatures, etc. As more new particulates bury old, some change and some do not.

 

Many of these changes are caused by bacteria eating buried dead organic matter. Pore water records this by keeping the products of these reactions. By studying this water, we know what type of reactions occurred and what type of material used to be in the sediment before it was changed.

Clint Miller

Images: Main image shows porewater being extracted by squeezer (Courtesy of ELeBer@ECORD_IODP). Inset images show Clint hard at work and Luzie Schnieders (ESO Geochemist) working at the squeezer (Courtesy of ELeBer@ECORD_IODP). The final image was supplied by Clint Miller and show how rhizones can collect pore water in softer sediments – this image is not from this expedition and is shown as an example of methodology only.

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Wildlife encounters

After just over a week at sea we are startling to settle into a routine. We work in 12 hour shifts with the majority of the team on board working either noon to midnight or vice versa. This means everyone gets to see sunset (day shift) or sunrise (night shift). These have been really variable and spectacular as different weather rolls in.

Since we arrived on site we’ve also been joined by dolphins every night. They stay around for most of the night, perhaps catching fish that are attracted to the ships lights. They generally disappear around 6am but did return one day during daylight hours to allow us to get some pictures! We also saw a sea turtle one day although that seems to have been a one off, or we’ve been to busy coring to spot anymore.

Sophie Green

Images courtesy of DSmith@ECORD_IODP (main image); GTulloch@ECORD_IODP (left and top right) and ELeBer@ECORD_IODP (bottom right and image below)

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Onshore from the Offshore Perspective

Xylolastro Panorama annotated

And now for some geology from Rob Gawthorpe – one of the scientists sailing on Expedition 381.

The location of the first IODP Expedition 381 borehole in the Gulf of Corinth gives a different view of the onshore Corinth Rift geology. In the early morning light the view from the Fugro Synergy gives an excellent overview of the southern shores of the Gulf of Corinth and the northern Peloponnesus around the town of Xylokastro.

To the east of Xylokastro, marine terraces are clearly seen as sub-parallel ‘steps’ in the landscape rising southward, recording older shorelines formed during previous sea-level highstand, now uplifted in the footwall of active faults under the gulf. (Editor note: see diagram for an explanation of footwalls and hangingwalls). The terraces extend back in time to at least 0.6 Ma (million years) and unconformably (not successive in age) overlie older deep-water syn-rift sediments that record the early phase of evolution of the Corinth Rift when the rift was mainly located onshore.

untitledImage courtesy of http://www.thinglink.com

The Sythas River flows along the major valley south of Xylokastro. The high topography at the head of this valley is in pre-rift rocks that are in the footwall of the now inactive southern border fault of the Corinth Rift.  In this part of the rift it is called the Killini-Trikala-Kefalari Fault.

West (right) of Xylokastro, the prominent N-facing hillside near the coast that is in shadow is the West Xylokastro Fault. This fault is thought to have been active between ca. 1.8 to 0.8 Ma (million years).  Behind (S) of this fault, the mountain Mavro Oros, is composed of older fluvial (river) and deltaic deposits that fed Late Pliocene/earliest Pleistocene turbidites (sediment flows driven by gravity) exposed along the Sythas valley.

On the right of the photo, light coloured cliffs are deltaic and turbidite deposits interpreted to be synchronous (occurring at the same time) with activity on the West Xylokastro Fault, but now uplifted in the footwall of the active faults under the Gulf. The higher cliff is the Evrostini delta that prograded into >600 m of water (indicated by the height of its’ foresets – the inclined part of a delta formed as sediments are laid down along the delta front). The lower cliffs, near the coast, are deep-water turbidite deposits sourced from the Evrostini delta.  Both delta and turbidites are now uplifted in the footwall of active faults under the gulf, with the fluvial topsets of the Evrostini delta now elevated to ca. 1000 m above sea-level.

In addition to IODP drilling in the Gulf of Corinth, a complementary project (Syn-Rift Systems project) led by the University of Bergen has just started drilling the onshore sediments near the town of Xylokastro, targeting the older syn-rift sediments.

More information about the onshore geology around Xylokastro can be found at:

http://onlinelibrary.wiley.com/doi/10.1111/bre.12260/full

Main panoramic image courtesy of RGawthorpe@ECORD_IODP

 

The first core on deck!

The preparations onboard continued overnight and into the 23rd October with the whole science party very excited about receiving and seeing the very first core. During the night the ship was visited by a school of dolphins – and they returned for the time of the arrival of the first core! We had the whole spectrum of weather during the day, including a squally rainstorm, lightning and a double rainbow which we hope was a good omen for successful coring and a productive expedition!

The scientists were very happy to see the first core arriving on deck at 9:30 (local time) in the evening. This is the first time for the group to take samples for analysis on board. Their findings will help them make decisions about the drilling operations during the expedition and are the beginning of the large number of scientific results that will be generated by the expedition. The palaeontologists look for small fossils that give us the age of the sediments, the sedimentologists look at the composition of the sediments, and the geochemists measure the chemistry of the water in the sediments. Finally the cores are run through a machine (a “multi sensor core logger”) which measures the physical properties of the cores. We will explain more about these measurements, how they are made and how they will be used as we progress through the expedition.

Lisa McNeill

Images courtesy of DSmith@ECORD_IODP and LSchnieders@ECORD_IODP (rainbows).

Images: Main picture – the scientists eagerly await getting sight of the first core; a double rainbow is hopefully a good omen; the first core is extracted from the core barrel; the core undergoes initial curation and cutting into sections on the core bench ( showing Patrizia Geprags, Graham Tulloch and Apos Tsiligiannis); the core then goes into core curation (showing Patrizia Geprags) before moving into the MSCL (multi-sensor core logger) container for physical properties measurements (showing Laurence Phillpot).

We are Sailing….

We have finally started IODP Expedition 381! At 8pm on 22nd October the DV Fugro Synergy set sail from Corinth port and headed to the first drill site. The science party and ESO team had been preparing and training for when the cores arrive and enjoying some time off the ship in Corinth, including stocking up with snacks for the long time at sea. Half of the science party were up to enjoy the departure. The transit was short out to the first site: Site M0078 is located only a few kilometres northwest of the port. By ~9:30pm the ship had already arrived on site. The process of preparing for coring involves many stages, including accurately positioning the ship above the drill site using a beacon system and the ship’s dynamic positioning and building a stable dynamic positioning model, plus calculating the depth to the seafloor very precisely. Then the drill pipe is gradually lowered to the seafloor. At this site the water depth is about 850 m and so the process of running drill pipe takes some time! The drill bit came into view above the sea devil at 16.32 local time on October 23rd.

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Lisa McNeill

An aside on times……..On all our blogs we will be using the ship time as local time. To avoid confusion part-way through when the clocks go back for winter, the vessel moved their clocks back on sailing, so local time for the ship is now GMT+2.

Image: Thanks to Erwan Le Ber for his image of the final line leaving the shore at Corinth. ELeBer@ECORD_IODP; DSmith_ECORD_IODP the drill bit comes into view

Lights, Camera, Action!

It was a bright sunny day so we didn’t need the lights, but we did have the cameras and action when the media day for Expedition 381 Corinth Active Rift Development happened on October 19th. It is important for ECORD that we let everyone know what we are doing, and the science we are researching, with every expedition we run, especially in the local area where drilling occurs.

The first thing we do is draft a press release in collaboration with our Co-chiefs Lisa and Donna. On the day of the press conference this is released to the media offices of all the institutions linked to any of the science party, as well as national and international press agencies. The press conference is a chance for ESO and the Co-chiefs to set the scene for the expedition, and answer any questions that the press may have. After that it is down to the vessel for more interviews and a look round the science containers and the drill floor.

This is the part that really captures the imagination. As you stand on the quayside the vessel looms above you looking very impressive indeed. It is an environment that is so unlike anything that most people experience day to day that it is important to show the public what it involves, how we drill, and what our aims and objectives are. So chatting to the scientists sailing and the operational team  is a really important part of the process.

This process will be repeated during the Onshore Science Party when the cores will be shown and the press can see the whole science party working in the lab spaces at MARUM, Center for Marine Environmental Sciences, University of Bremen, Germany. But for now we wait in anticipation for the first cores to come up and be captured on film!

Images courtesy of DSmith@ECORD_IODP and CCotterill@ECORD_IODP

Images: Main picture, Co-chief Lisa McNeill is interviewed down by the science containers; Others: Press conference in Loutraki; Interviews on the quayside; some of your trusty outreach team on-board alongside Educator Martin Bottcher; Interview with Co-chief Donna Shillington on the bridge; repeat of main picture and finally Ulrike dons the Personal Protective Equipment (PPE) of steel toe caps, hardhat, overalls and glasses for the first time!

Transit from Malta

This blog is a little out of order, but as someone not sailing, the transit from Malta to Corinth was something I didn’t get to see or experience. So Laurence, one of the ESO European Petrophysics Consortium team wrote this for us all.

“Prior to the collection of 9 members of the science party in Corinth, many of the ESO (ECORD Science Operator) team joined the Fugro Synergy DV earlier along its journey in Valetta, Malta. There were several reasons for doing this, chief among which was to complete the mobilisation process and prepare labs ahead of the offshore science party joining. Much of this work consisted of last minute adjustment-type jobs and ‘tweaking’; but as most people know it’s these jobs that can seem to take up a disproportionate majority of time. And since the transit time from Malta was only a couple of days, joining early was the perfect solution.

As with all MSP’s I have experienced so far there was an atmosphere of “hurry up and wait” aboard the vessel during its transit. That is to say, anything that could be done at the time needed to be. Anything that couldn’t yet be completed needed to be completed as much as possible. As far as I understand, this work ethic exists because there are a lot of unknowns when operating aboard a new drilling vessel over and above the usual unknowns of working at sea. Such as the weather and its various effects on operations, and connectivity with the world not on board the vessel.

The other key reason (as I saw things) for joining the vessel early was to give the team an opportunity to get to know one another. Now I’m not talking about the ESO team – we’re all already pretty tight – I’m talking more about the wider team on board the vessel. This includes the drilling team, captains and officers on the various shifts, stewards, engineers, cooks and everybody else here to complete their individual specialisms. The Fugro team on board were and have continued to be extremely welcoming and helpful in all situations and I for one am looking forward to working with them when we depart for our first site.

Speaking of weather the Mediterranean Sea during this transit was beautiful and calm, providing the team with easy sailing and simplified operations but also ample opportunities to attempt to capture some of this beauty on film. The main picture is my attempt to capture this!”

Many thanks for this Laurence, and may the rest of the expedition see calm seas and fair sailings!

Image courtesy of LPhillpot@ECORD_IODP