IODP Expedition 330

Louisville Seamount Trail

Daily Science Report for 31 December 2010

LOCATION: Site U1373 (Prospectus Site LOUI-6A). Position: 28°33.93' S Lat., 173° 16.78' W Long.

SCIENCE UPDATE: After Site U1372 was abandoned the ship arrived at the new Site U1373 (approved alternate Site LOUI-6A) in the late afternoon. The first Site U1372 meeting was held at noon and the Sedimentology and Paleontology laboratory groups presented the results of their shipboard investigations and analyses. Presentations from all other laboratory groups will follow in the next days. At midnight, the New Year was greeted by the traditional bell ringing ceremony on the ship's bow.

Daily Science Report for 30 December 2010

LOCATION: Site U1372 (Prospectus Site LOUI-1C). Position: 26°29.6'S Lat. 174°43.75'W Long.

SCIENCE UPDATE: After it became clear that the drill pipe would remain stuck, the decision was made to sever the drill string at a depth of about 90 mbsf. Since this operation leaves only a short interval of open hole for logging, and any logging operations would be very risky after the formation got further weakened by the explosion; it was decided not to attempt any downhole logging at this site. A science meeting was held at noon to discuss the situation. The science party agreed to a proposal by the co-chiefs to go to the approved Alternate Site LOUI-6A, which is located on a similar age seamount just 146 nautical miles to the SE. It is hoped that drilling at LOUI-6A will yield the minimum number of igneous flow units that is necessary for the precise determination of the paleolatitude from a seamount located at the old end of the Louisville chain and thereby complement the results that we got so far from the abandoned Site U1372. Since no new cores could be recovered today, the science party focused on describing the rocks retrieved from Cores U1372A-37R and -38R and started writing their site report chapters for Site U1372.

Daily Science Report for 29 December 2010

LOCATION: Site U1372 (Prospectus Site LOUI-1C). Position: 26°29.6'S Lat. 174°43.75'W Long.

SCIENCE UPDATE: The retrieved material and percentage of recovery of today's Cores U1372A-36R (223.4-228.2 mbsf), -37R (228.2-228.9 mbsf), and -38R (228.9-232.9 mbsf) of 5%, 129% and 85%, respectively, show the transition from the thick pile of hyaloclastites into lava flows again. To the delight of everyone, Core U1372A-37R retrieved the upper part and -38R the central part of a dense lava flow unit containing abundant olivine phenocrysts. Whereas the olivines in the upper part of the flow are completely altered and transformed to secondary minerals, all olivines in the central part of the flow (Sections U1372A-38R-1 to -3) are fresh. Unfortunately the hole conditions deteriorated in the afternoon (probably due to material falling in from the crumbly and clast-rich hyaloclastic material between ~170 and 230 mbsf). Despite great effort to clear the hole, the drill pipe got stuck shortly before midnight.

Daily Science Report for 28 December 2010

LOCATION: Site U1372 (Prospectus Site LOUI-1C). Position: 26°29.6'S Lat. 174°43.75'W Long.

SCIENCE UPDATE: After getting used to generally good to exceptional recovery in the upper 100 m of the igneous basement at this site, today's Cores U1372A-26R (170.6-175.4 mbsf), -27R (175.4-180.2 mbsf), -28R (180.2-185.0 mbsf), -29R (185.0-189.8 mbsf), -30R (189.8-194.6 mbsf), -31R (194.6-204.2 mbsf), -32R (204.2-209.0 mbsf), -33R (209.0-213.8 mbsf), -34R (213.8-218.6 mbsf), and -35R (218.6-223.4 mbsf) were retrieved with fluctuating recovery between 19% and 115%. This is caused by the predominance of hyaloclastics in this interval resulting in frequent jamming of the core catcher and also in breakouts in the formation that get stuck between the drill collars and the borehole wall. The recovered hyaloclastite hosts many small (lapilli-size), irregular-shaped fragments of aphyric vesicular basalt in a matrix containing fresh volcanic glass particles. Intervals that stretch over several cores are surprisingly well preserved. Meanwhile more results from shipboard measurements from samples of the conglomerate/breccia succession between Core U1372A-4R and -8R (between the young, pelagic sediment cover and the beginning of the igneous “basement”) were generated. It appears that the clasts that make up this succession exhibit a large contrast in p-wave velocity that varies between the different clast types (between 3.5 to almost 6.5 km/sec). This might explain the distinct seismic reflectors of this interval in the seismic site survey data.

Daily Science Report for 27 December 2010

LOCATION: Site U1372 (Prospectus Site LOUI-1C). Position: 26°29.6'S Lat. 174°43.75'W Long.

SCIENCE UPDATE: Cores U1372A-21R (145.0-149.2 mbsf), -22R (149.2-156.2), -23R (156.2-161.0), -24R (161.0-165.8), and -25R (165.8-170.6) were retrieved with and average recovery of only 28%. The low recovery rate is most likely caused by the heterogeneous nature of the rocks containing both soft and hard intervals. The core catcher (device at the end of the core barrel that prevents the core from falling out) got jammed several times by individual hard clasts thereby preventing further material to enter. Cores U1372A-21R to -25R are composed of a volcanic breccia with larger, boulder-size and very fresh, plagioclase-phyric clasts and a greenish, sand-size matrix that appears to be sedimentary (a 2 cm-size interval shows apparent cross-bedding structures). Some clasts exhibit thin altered glass margins. Meanwhile the investigation of the carbonate-cemented clastic conglomerate/breccia succession between Cores U1372A-4R and -8R continues. This interval (13.5- 45.6 mbsf), located between the uppermost thin layer of pelagic Pliocene to recent sediments and the igneous basement (lava flows) of the seamount, obviously contains material from the late stage of volcanism at this site. The paleontologists are trying hard to further constrain a more specific age for the micritic limestone matrix which is currently only identified as "mid to late Cretaceous." However, doing this by investigating thin sections that arbitrarily cut through the foraminifer fossils and reveal no sight of the smaller nannofossils (much smaller than the thickness of a thin section) proved to be a difficult or even impossible task.

Daily Science Report for 26 December 2010

LOCATION: Site U1372 (Prospectus Site LOUI-1C). Position: 26°29.6'S Lat. 174°43.75'W Long.

SCIENCE UPDATE: Cores U1372A-19R (138.2-143.0 mbsf) and -20R (143.0-145.0 mbsf) retrieved brecciated igneous rocks with a recovery rate of 74% and 55%, respectively. These cores are currently being described. After having penetrated 100 m of igneous rock, the paleomagnetic group has announced a positive interim evaluation: all measured rocks show a surprisingly low, drilling induced, magnetic overprint. This is believed to result (at least in part) from the exclusive use of non-magnetic core barrels during this expedition. The necessity of today's scheduled drill bit change provides a welcome opportunity for all lab groups to catch up with core description and shipboard measurements.

Daily Science Report for 25 December 2010

LOCATION: Site U1372 (Prospectus Site LOUI-1C). Position: 26°29.6'S Lat. 174°43.75'W Long.

SCIENCE UPDATE: Cores U1372A-13R (90.1-99.7 mbsf), -14R (99.7-109.3 mbsf), -15R (109.3-119.0 mbsf), -16R (119.0-128.7 mbsf), -17R (128.7-133.4 mbsf), and -18R (133.4-138.2 mbsf) were drilled with an average penetration rate of 2.4 m/hr and retrieved a volcanic lava succession with an average recovery rate of 50%. The recovered rocks are variable altered portions of amygdale lava flows including small intervals of brecciated material cemented by a highly altered, greenish matrix. Downhole, the recovered rocks become more brittle, which hampers core splitting and sample handling. The paleontologists are still investigating the carbonate matrix in Cores U1372A-4Rto -8R to further constrain the deposition age of the volcaniclastic breccia. However, the identification of one small Inoceramus shell fragment (a clam that became extinct at the end of the Cretaceous) and the occurrence of the foraminifer genus Heterohelix, confirm our initial assumption that these breccias were formed during the late stage of the seamount (eroded island?) in the mid- to late Cretaceous. In the afternoon, all activities came to a halt when Santa Claus entered the ship and all well-behaved expedition participants received their presents. The ship's catering crew provided an overwhelming spread of delicatessen food that surpassed even the wildest expectations.

Daily Science Report for 24 December 2010

LOCATION: Site U1372 (Prospectus Site LOUI-1C). Position: 26°29.6'S Lat. 174°43.75'W Long.

SCIENCE UPDATE: Cores U1372A-9R (51.7-61.3 mbsf), -10R (61.3-70.9 mbsf), -11R (70.9-80.5 mbsf) and -12R (80.5-90.1 mbsf) were retrieved with an exceptional high average recovery rate of 76%. With the identification of the first "in situ" lava flow in Core U1372-8R, the top of the igneous basement is defined at 45.6 mbsf (just about 10 m shallower then expected based on seismic data). All subsequent Cores U1372A-9R to -12R returned more lava flows and hence confirmed this interpretation. However, Core U1372A-9R shows evidence for mixture or shallow intrusion of lava into unconsolidated sediment and is therefore interpreted as peperite. Subsequent cores (beginning in Section U1372A-10R-2 and below) show almost textbook-like examples of lava flow successions with rubbly, autobrecciated, vesicle-rich, and highly altered top and bottom zones and massive, less altered to fresh interior parts. Some of these flows contain abundant olivine phenocrystals that show nice transitions from completely altered (exterior flow parts) to very fresh (interior flow parts) sometimes within a single piece of core material over intervals of just a few centimeters. Everyone on board is awaiting the arrival of Santa Claus in the coming morning and is hoping for many presents in the form of continued recovery of many, well-preserved lava flows.

Daily Science Report for 23 December 2010

LOCATION: Site U1372 (Prospectus Site LOUI-1C). Position: 26°29.6'S Lat. 174°43.75'W Long.

SCIENCE UPDATE: Cores U1372A-6R (23.5-32.8 mbsf), U1372A-7R (32.8-42.1 mbsf), and U1372A-8R (42.1-51.7 mbsf) recovered more of the colorful volcaniclastic, carbonate-cemented breccia with exceptional recovery rates of 50%, 79% and 89%, respectively. The breccias include large intervals (boulder-size) of surprisingly well-preserved volcanic rock some of which contain abundant fresh olivine crystals. This discovery was greeted with great delight, as fresh olivine can be used for a range of petrological and geochemical investigations. These include assessments of temperature and He isotopic composition of the magma source (which were never done for Louisville before due to a lack of suitable olivine in the hitherto available dredge samples). All descriptive lab groups are busy describing the recovered rocks. The paleomagnetism group is applying the “conglomerate test” to all vertically oriented pieces by measuring their magnetic orientation to identify the relative timing of magnetization and deposition of the clastic succession. At noon, the first 12:00 sampling meeting was held, were the recovered rocks where briefly discussed and the exact location of samples taken for shipboard studies (e.g. thin sections, geochemistry, physical properties etc.) were identified.

Daily Science Report for 22 December 2010

LOCATION: Site U1372 (Prospectus Site LOUI-1C). Position: 26°29.6'S Lat. 174°43.75'W Long.

SCIENCE UPDATE: After the pressure test for the new non-magnetic sinker bar was successfully completed in the morning hours (the unit did not leak), the drill string tagged seafloor at 1968.5 meters below rig floor. Hole U1372A was spudded at 08:50 hr and the first core of Exp. 330 was recovered shortly afterwards. In total, five cores (U1372A-1R to -5R) were retrieved before midnight. Whereas Core U1372A-1R retrieved only ~10 cm of unconsolidated sediment, Cores U1372A-2R (0.1-9.7 mbsf) and -3R (9.7-13.5 mbsf) recovered 7.55 m and 2.74 m of soft sediment respectively (corresponding to 79% and 72% recovery). Subsequent cores U1372A-4R (13.5-18.0 mbsf) and -5R (18.0-23.5 mbsf) retrieved cemented volcaniclastic lithologies with 100% and 115% recovery.
For all cores, the non-magnetic core barrel assembly was used and fluorescent microspheres (for microbiologic contamination testing) were deployed in Core U1372A-1R. To everyone's excitement and joy, the five cores yield a variety of different lithologies and rock types.
Cores U1372A-1R to -3R recovered a light-brown foraminifer sand (containing mainly planktonic foraminifers and epiclastic volcanic fragments). Preliminary biostratigraphic age determinations reveal recent to Pleistocene (U1372A-1R), Pliocene to Pleistocene (U1372A-2R) and early Pliocene (U1372A-3R) ages. Cores U1372A-4R and -5R recovered colorful volcaniclastic breccia composed of pebble- to bolder-size clasts in a white carbonate matrix. The volcanic clasts have different lithologies and their preservation stage ranges from very altered to almost fresh.
Samples for microbiologic investigation were taken from four cores and prepared for postcruise molecular and cell count studies. Cultivation experiments were set up from Core U1372A-1R.

Daily Science Report for 21 December 2010

LOCATION: Site U1372 (Prospectus Site LOUI-1C). Position: 26°29.6'S Lat. 174°43.75'W Long.

SCIENCE UPDATE: After crossing the Kermadec Trench in the morning, the vessel arrived at Site U1372 at 17:00 hr. A science meeting was held at noon to inform the science party about the upcoming operations and to sort out last details of shipboard sampling and core handling for soft sediments. The Operations Superintendent conducted a second rig floor tour for scientists on the midnight to noon shift. Co-chief Koppers gave a presentation of the expedition objectives to all interested members of the ships crew and USIO personnel. After the drill string is assembled, it is planned to pressure-test the new non-magnetic sinker bar by running it down the drill pipe to a water depth shortly above seafloor, which is measured at 1960.3 meters below rig floor by the Precision Depth Recorder (PDR).

Daily Science Report for 20 December 2010

LOCATION: Underway to Site U1372 (Prospectus Site LOUI-1C). Midnight Position: 28°35.1'S Lat. 176°24.6'W Long.

SCIENCE UPDATE: The science party continues to prepare for the arrival of the first core. Details of sampling for shipboard analyses were further refined including the integration of microbiology sampling into the core handling process. Geochemists and Paleomagnetists are testing their instruments including setting up the newly acquired XRF spot scanner that will be used for the first time on this expedition. All core description groups continue practicing the use of DESClogik and refining their data entry templates. An introduction to the microscope lab and the process of taking and uploading microphotographs was given in the morning. During a second meeting regarding postcruise research division, all outstanding questions were unanimously resolved. At noon the scientific party started migrating to shift schedule. In the afternoon, the Operations Superintendent conducted a rig floor tour for the day shift scientists. A similar tour will follow the next morning for the night shift scientists.

Daily Science Report for 19 December 2010

LOCATION: Underway to Site U1372 (Prospectus Site LOUI-1C). Midnight Position: 31°29.4'S Lat. 179°34.9'E Long.

SCIENCE UPDATE: Preparations for core processing and description continued. Most lab groups have submitted their first draft of the "Methods" chapter (explanatory notes) for the cruise reports. Co-Chief Scientists and Expedition Manager are busy reviewing them. Template set-up in the DESCLogik application for all four core-describing groups (sedimentology, petrology, alteration, structure) and for biostratigraphers is in an advanced state. A selection of core sections from Leg 197 (Emperors Seamounts) are used for practicing core description and data entering. In the afternoon, the Operations Superintendent conducted a pre-spud meeting with the expedition management team, ship and drilling officers, the Schlumberger Logging Engineer and third-party borehole magnetometer specialist. The day was concluded by a presentation about downhole logging methods and instruments given by the Logging Staff Scientist.

Daily Science Report for 18 December 2010

LOCATION: Underway to Site U1372 (Prospectus Site LOUI-1C). Midnight Position: 34°41.0'S Lat. 176°47.4'E Long.

SCIENCE UPDATE: The JOIDES Resolution departed Auckland at 08:00 and started its ~3.5 day voyage to the first drill site, the second northernmost seamount of the Louisville seamount chain. Science meetings and core description training resumed shortly after departure. The Curator and Expedition Project Manager conducted “core flow walk through” tours for all scientists including a discussion of shipboard sampling strategies. Sedimentologists and paleontologists learned to use the SampleMaster application to record samples that are taken for shipboard studies. First lab groups submitted their draft for the "Methods" chapter of the cruise report.

Daily Science Report for 17 December 2010

LOCATION: Wynyard Wharf, Auckland, New Zealand

SCIENCE UPDATE: Lab teams composed of scientists and technical staff continue learning labs, instruments, and how to document the methods they want to apply. Core describers started practicing core description with the DESCLogik software application on selected cores from ODP Leg 197 (Emperors Seamounts), which are supposed to have a similar lithology as anticipated for Exp. 330. Last evening on land!

Daily Science Report for 16 December 2010

LOCATION: Wynyard Wharf, Auckland, New Zealand

SCIENCE UPDATE: All scientists were introduced to the new data capture concept DESClogik. Subsequently, core-describing scientists split up into lab groups to further learn details of the new data capture applications. All other scientists started writing up the "Methods" chapter for the cruise report, met with their respective lab technicians, and were introduced to analytical instruments. Core describers started reviewing DESCLogik templates that are provided to capture descriptive data for the database.

Daily Science Report for 15 December 2010

LOCATION: Wynyard Wharf, Auckland, New Zealand

SCIENCE UPDATE: Scientists and technical staff began shipboard orientations and planning for Exp. 330. Activities included personnel introductions, overview of expedition science objectives by co-chief scientists, and an introduction into all the aspects of an IODP expedition and specifics of Exp. 330. The Captain and Ship's Officers held a safety and introductory meeting and ship and safety tours were conducted for the expedition participants afterwards. More public relation ship tours were given throughout the day organized by the New Zealand IODP office. Several scientists attended public lectures at the Auckland Museum in the evening. Co-chief Scientist Koppers gave an overview presentation on Exp. 330 background and science objectives to an audience of over one hundred New Zealand scientists and citizens.

Daily Science Report for 14 December 2010

LOCATION: Wynyard Wharf, Auckland, New Zealand

SCIENCE UPDATE: Co-Chief Scientists, Staff Scientist and USIO personnel continued crossing over with off-going USIO staff. Several VIP tours were conducted in cooperation with the Auckland Museum and the New Zealand IODP office. Exp. 330 scientists boarded the ship at 11:15 and started to explore their new home. Co-chief scientists gave a science talk at a VIP lunch function at Auckland Museum in the afternoon. Most members of the Exp. 330 science party also attended this event (organized by the New Zealand IODP office) and were given tours of the museum afterwards. Loading activities (off and on loading) continued.

Daily Science Report for 13 December 2010

LOCATION: Wynyard Wharf, Auckland, New Zealand

SCIENCE UPDATE: Expedition 330 Chief Scientists and USIO staff boarded the ship at 10:00 shortly after the arrival of the vessel. Crossover activities with offgoing USIO staff and scientists from previous Expedition 329 continued throughout the day. Co-Chief Scientists discussed upcoming science meeting schedule with EPM. Arriving and off-going shipments were staged on the pier.