IODP Expedition 321
Pacific Equatorial Age Transect 2
Daily Science Report for 31 May 2009
LOCATION: At Hole U1337D (PEAT-7C), 3° 50.0' North, 123° 12.3' West
SCIENCE UPDATE: APC Cores U1337D-8H through 26H advanced from 65.0 to 237.7 m DSF, 179.1 m recovered (103.7%). Switched to XCB coring to penetrate through a ~0.5 m porcellanite ("baby chert") layer. Core U1337C-27X advanced from 237.7 to 241.4 m DSF, 2.23 m recovered (60.3%).
Scientists completed processing cores from Hole U1337C and began working on cores from Hole U1337D. Cores U1337C-25X through 33X were imaged and described. Bottom section of Hole U1337C contained nannofossil chalk with sharp color change from light green to pale yellow ~393 m CSF-A. The base of Hole U1337C continues into basement 34 cm as aphanitic basalt. Basalt is fractured and cemented with 2 stages of calcite veins, the latest showing mm-sized euhedral calcite crystals along surface of incompletely filled fracture. Cores U1337D-1H through 5H contain mixed lithology of calcareous and biosiliceous ooze showing rhythmic variability reflecting classic carbonate glacial cyclicity.
Daily Science Report for 30 May 2009
LOCATION: At Hole U1337D (PEAT-7C), 3° 50.0' North, 123° 12.3' West
SCIENCE UPDATE: XCB Cores U1337C-25X through 33X advanced from 365.2 to 440.3 m DSF, 72.4 m recovered (96.4%). Offset 20 m west of Hole U1337C and started coring Hole U1337D to cover gaps between cores in previous holes and to obtain more sediments for postcruise research. APC Cores U1337D-1H through 7H advanced from 0 to 65 m DSF, 64 m recovered (98.5%).
Cores U1337C-14X through 24X have been split, imaged and described. Major lithologies comprised of nannofossil chalk, with varying amounts of biosiliceous components. Sediments gradually alternate between white nannofossil chalk and light greenish gray nannofossil chalk with diatoms and radiolarians. All cores from Hole U1337C have completed with whole round fast-track, multisensor track and natural gamma measurements. Total organic carbon measurements for Site U1337 have been completed.
Daily Science Report for 29 May 2009
LOCATION: At Site U1337 (PEAT-7C), 3° 50.0' North, 123° 12.3' West
SCIENCE UPDATE: APC Cores U1337C-7H through 9H advanced from 192.8 to 221.3 m DSF, 29.6 m recovered (104%). XCB Cores U1337C-10X through 24X advanced from 221.3 to 365.2 m DSF, 136.2 m recovered (94.6%).
Cores U1337C-4H through 14X have been split, imaged and described. Sediments comprised of alternating lithologies of diatom nannofossil ooze and nannofossil ooze containing varying amounts of biosiliceous components. Laminated diatom intervals are up to 150 cm thick at time and contain abundant Thalassiothrix sp. diatoms. Core U1337C-11X-CC also contained approximately 15 cm of porcellanite/chert breccia. Micropaleontological samples from Hole U1337C are being processed for detailed assemblage and biostratigraphic data.
Daily Science Report for 28 May 2009
LOCATION: At Hole U1337C (PEAT-7C), 3° 50.0' North, 123° 12.3' West
SCIENCE UPDATE: APC Cores U1337C-1H through 2H advanced from 0 to 11.4 m DSF, 11.61 m recovered (101.8%). Wash down to ~169.4 m DSF. After recovering wash barrel U1337C-3W, continued APC coring for the next 23.4 m DSF. APC Cores U1337A-4H through 6H advanced from 169.4 to 192.8 m DSF, 23.91 m recovered (102.2%). Core 6H was advanced by recovery.
Cores U1337C-1H through 2H were split, imaged and described. The mudline was recovered in Core U1337C-1H. Sediments near the top of Core 1H contained dark brown calcareous ooze that gradually transition to an alternating and highly mottled sequence of nannofossil ooze and biosiliceous ooze below. Cores are being processed through the track systems and data loaded for stratigraphic correlation. A preliminary science meeting was held to discuss data from Holes U1337A and U1337B.
Daily Science Report for 27 May 2009
LOCATION: At Site U1337 (PEAT-7C), 3° 50.0' North, 123° 12.3' West
SCIENCE UPDATE: After attempting to recover the stuck core barrel, a decision was made to end operations at Hole U1337B and move on to Hole U1337C. No recovery on XCB Core U1337B-28X. Offset ship 20m west of Hole U1337B and preparing to spud Hole U1337C.
Cores U1337B-15H through 27H were imaged and described. Sediments alternate cyclically between mixed lithologies of nannofossil and biosiliceous (mostly diatom) ooze. A series of laminated diatom ooze layers were recovered with intervals up to 1.5m thick. Numerous dolomite concretions were encountered both within cored intervals and as fall-in debris in core tops. Hole U1337B samples have been processed for micropaleontological investigation in pace with the splitting of the cores throughout the day. Range chart data containing estimates of preservation and abundance at the species level have been acquired using samples from Hole U1337A in order to improve depth resolution of biostratigraphic events. Preliminary age depth plots using all four plankton groups provide a robust framework for subsequent age model work.
All cores from Hole U1337B have completed with whole round fast-track, multisensor track and natural gamma measurements. Moisture and density (MAD) measurements were completed for all samples from Hole U1337A. Geochemical analyses continue on interstitial water and bulk sediment samples from Hole U1337A.
Daily Science Report for 26 May 2009
LOCATION: At Site U1337 (PEAT-7C), 3° 50.0' North, 123° 12.3' West
SCIENCE UPDATE: APC Cores U1337B-11H through 27H recovered from 96 to 245 m DSF, 148 m recovered (99.2%). Switched to XCB and cored to 251.9 m DSF (Core U1337B-28X). XCB core barrel is stuck in the formation and we are attempting to clear around core barrel. Cores U1337B-1H through 14H have been split, imaged and described. Lithological descriptions consistent with same intervals recovered in Hole U1337A and consist of cyclic alternations between main lithologies that reflect varying amounts of nannofossils, radiolarian and diatoms. Core U1337B-14H contains first appearance of interval rich in Thalassiothrix sp. diatoms interbedded with nannofossil ooze and diatom nannofossil ooze. Sediments are intensely bioturbated and diagenetic thin color bands and color lamina overprint most of the lithologies. Several large dolomite concretions and thin dolomite layers were found throughout this interval. Micropaleontological samples from Hole U1337A continue to be processed for detailed assemblage and biostratigraphic data. The nannofossil biostratigraphy between Holes U1337A and U1337B is consistent.
Daily Science Report for 25 May 2009
LOCATION: At Hole U1337B (PEAT-7C), 3° 50.0' North, 123° 12.3' West
SCIENCE UPDATE: Downhole logging was completed at Hole U1337A ~0715 h with the final tool string-FMS-Sonic. Offset 20 m west of Hole U1337A and started coring Hole U1337B to cover gaps between cores in the first hole. APC Cores U1337B-1H through 10H recovered from 1 to 95 m DSF, 94.5 m recovered (99.5%). Lithology and ages are similar to Hole U1337A. Cores 1H-6H finished with whole-round track data collection. Whole-round susceptibility and density data indicate ~5 m offset is working well to obtain a nearly complete section for cores recovered to ~95 m.
Daily Science Report for 24 May 2009
LOCATION: At Hole U1337A (PEAT-7C), 3° 50.009' North, 123° 12.352' West
SCIENCE UPDATE: All cores from Hole U1337A have been imaged and described. Cores 35X through 39X, sediments are mainly nannofossil chalk but thin intervals of slightly increased radiolarian content continue cyclic alternations throughout the cores. Sediments below Cores U1337A-39X are uniformly nannofossil chalk. Small fragments (<1mm) of volcanic glass and glassy pumice are observed in most of the lower sections with occasional larger fragments, some up to 4cm. Sediment biscuits are formed from drilling disturbance in Cores U1337A-34X and below. Core U1337A-48X contains aphanitic basalt with calcite veins indicating penetration into the basement seafloor.
Logging activities continued through out the day. After finishing the second pass with the triple combo tool sting the VSI (vertical seismic imaging) was prepared for deployment. Mammal observation began at dawn and was cleared before ultrasonic air guns were 'shot'. VSI measurements were made at 16 stations (~15 m apart) starting at the bottom of Hole U1337A. VSI was completed by dusk and began preparing the FMS-sonic tool string for logging.
Daily Science Report for 23 May 2009
LOCATION: At Site U1337 (PEAT-7C), 3° 50.009' North, 123° 12.352' West
SCIENCE UPDATE: XCB Cores U1337A-47X through 48X recovered from 433.6 to 449.8 m DSF, 16.24 m recovered (100.3%). The basement was recovered in Core 48X. The Oligocene/Miocene boundary was recovered in Section U1337-48X-3, as determined by the presence of the nannofossil biomarker Sphenolithus delphix. The micropaleontology lab continues to process samples and refine biostratigraphic datums. Cores U1337A-24X through 30X have been imaged and described. Major lithologies include nannofossil ooze with diatoms and nannofossil ooze with radiolarians. Lithology alternates between white to light bluish gray nannofossil ooze with diatoms and light greenish gray nannofossil ooze with radiolarians. Light bluish gray may be cyclic, every 120 cm (Core U1337A-28X). Cores U1337A-28X through 43X have completed with whole round fast-track, multisensor track, and natural gamma. Thermal conductivity measurements were completed on all cores.
Logging activities began around 1200 h upon completion of coring at Hole U1337A. After testing the wireline heave compensator, logging began with the triple combo tool string. The first pass of the triple combo tool string was completed around 2100 h.
Daily Science Report for 22 May 2009
LOCATION: At Site U1337 (PEAT-7C), 3° 50.009' North, 123° 12.352' West
SCIENCE UPDATE: XCB Cores U1337A-27X through 46X recovered from 242.2 to 433.6 m DSF, 168.9 m recovered (88.2%). Cores U1337A-13H through 23X have been imaged and described. Sediments show 50-100 cm scale alternations between lithologies that reflect varying amounts of diatoms, radiolarians and nannofossils. Cores 18H through 23X show numerous intervals of laminated nannofossil diatom ooze containing abundant thalassiothrix sp. Extensive diagenetic color banding and burrow haloes occur and numerous dolomite concretions (cm-sized) are found throughout this interval. The deepest core retrieved so far (U1337A-46X) has an age between 21 Ma and 22 Ma. The Miocene shows higher rates of sedimentation compared to the Pliocene/Pleistocene section. Four cores across the middle/late Miocene boundary are characterized by cm- to dm-thick diatom mats. The dominance of biogenic silica decreases progressively with increasing depth, resulting in better preservation of the biogenic carbonate. Cores U1337A-15H through 28X have completed with whole round fast-track, multisensor track, natural gamma and thermal conductivity measurements. Split core velocity and Moisture and Density (MAD) measurements were completed up to Core U1337A-23X.
Daily Science Report for 21 May 2009
LOCATION: At Site U1337 (PEAT-7C), 3° 50.009' North, 123° 12.352' West
SCIENCE UPDATE: APC Cores U1337A-10H through 21H recovered from 81.5 to 195.5 m DSF, 114 m recovered (106 %). XCB Cores U1337A-22X through 26X recovered from 195.5 to 242.2 m DSF, 36.4 m recovered (77.9%). Cores U1337A-3H through 12H have been imaged and described. Sediments alternate and are highly mottled between main lithologies that reflect variable amounts of diatoms, radiolarians and nannofossils. Diagenetic color banding and burrow haloes of manganese oxides are common throughout these lithologies. Several dolomitic concretions were recovered throughout the interval, some as large as 4 cm in diameter. Diatom mats occur in a few core catchers around 200 m CSF-A. Calcareous micro- and nannofossils become increasingly more abundant in Cores U1337A-24X through 26X. The Pliocene/Pleistocene boundary is close to 30 m CSF-A and the Miocene/Pliocene boundary is around 88 m CSF-A. The middle/late Miocene boundary occurs at about 230 m CSF-A. Pleistocene and Pliocene sedimentation rates show an average of 1.7 cm/ky. The late Miocene sedimentation rates show a slight increase to about 2.0 cm/ky. Cores U1337A-9H through 15H have completed with whole round fast-track, multisensor track data and with natural gamma measurements. Paleomagnetic measurements have been completed on Cores U1337A-2H through 8H.
Daily Science Report for 20 May 2009
LOCATION: At Site U1337 (PEAT-7C), 3° 50.009' North, 123° 12.352' West
SCIENCE UPDATE: Hole U1337A was spudded at 1115 hr establishing a seafloor depth of 4472 m DRF. First core on deck at 1145 h. APC Cores U1337A-1H through 9H were advanced from 0 to 81.5 m DSF, recovered 79 m (96.9%). Cores U1337A 1H-3H have been split, imaged and described. Cores 1H through 3H contain a colorful and highly mottled alternation of lithologies ranging between calcareous diatom ooze and nannofossil ooze with diatoms. Colors vary with lithology and range from very dark brown to very pale brown to olive. The upper 8 cores cover the interval from the latest middle Pleistocene to the early Pliocene. The Plio-/Pleistocene boundary occurs between 25 and 34 m (Core 4H); the 34 m level has an age of about 2.1-2.2 Ma, which gives an average sedimentation rate of 1.5 cm/ka for the uppermost sediments. Cores 1H-6H finished with whole-round track data collection. Interstitial water samples, discrete physical properties and paleomagnetic measurements have been collected and are being processed.
Daily Science Report for 19 May 2009
LOCATION: At Site PEAT-7C (U1337), 3° 50.009' North, 123° 12.352' West
SCIENCE UPDATE: Arrived on site ~1115 hr, began dynamic positioning over location of Site PEAT-7C, and started assembling and lowering drill string to seafloor. Chief scientists reviewed methods and site summary report from U1336. Ships crew, scientists and technical staff continue to prepare for coring, logging, and lab operations. Anticipate first core on deck early 20 May.
Daily Science Report for 18 May 2009
LOCATION: En route to Site PEAT-7C
SCIENCE UPDATE: Chief scientist gave presentation on PEAT-7C science objectives and operations plan to the scientists. The shipboard sampling plan was reviewed. Ship's crew, scientists and technical staff prepare for coring, logging, and lab operations at Site PEAT 7C. Estimated time of arrival (ETA) at site is noon of 19 May.
Daily Science Report for 17 May 2009
LOCATION: En route to Site PEAT-7C
SCIENCE UPDATE: Scientists submitted the first draft of Site U1336 report to co-chiefs and staff scientist. Ships crew, scientists and technical staff prepare for coring, logging, and lab operations at Site PEAT-7C. Estimated time of arrival (ETA) at PEAT-7C is morning of 19 May.
Daily Science Report for 16 May 2009
LOCATION: En route to Site PEAT-7C
SCIENCE UPDATE: Site U1336 science meeting was held. Scientists continue to work on Site U1336 site reports and methods.
Daily Science Report for 15 May 2009
LOCATION: En route to Site PEAT-7C
SCIENCE UPDATE: Scientists began assembling and integrating data from Site U1336 in preparation for first science meeting (Saturday, 16 May) and producing site reports.
Daily Science Report for 14 May 2009
LOCATION: En route to Site PEAT-7C
SCIENCE UPDATE: All cores from Site U1336B were processed. A pre-site operations meeting was held to discuss drilling and logging strategies. Scientists were introduced to logging tools and methods. Estimated time of arrival (ETA) at PEAT-7C is early 19 May.
Daily Science Report for 13 May 2009
LOCATION: En route to Site PEAT-7C
SCIENCE UPDATE: Cores U1336B-12H to 20H were split and described. Sediments are predominantly light greenish gray nannofossil oozes with light greenish gray color bandings. Occasional thin bands of nannofossil chalk were found in Core 19H to 20H. Paleomagnetic measurements were conducted on archive half sections and discrete samples were taken for physical properties and chemistry analyses.
Daily Science Report for 12 May 2009
LOCATION: En route to Site PEAT-7C
SCIENCE UPDATE: Scientists continue to process cores from Hole U1336B. Cores U1336B-5H to 11H were split and described. Sediments are predominantly nannofossil ooze with foraminifers. Sediment color changes downhole from pale yellow to light greenish gray in Core 11H. A science meeting was held to discuss details of the site summary report and methods.
Daily Science Report for 11 May 2009
LOCATION: En route to Site PEAT-7C
SCIENCE UPDATE: Due to the current transit time estimates and to ensure complete science programs at PEAT-7C and PEAT-8C, the operations plan was revised to go directly to Site PEAT-7C rather than coring another hole at Site PEAT-5C (U1336). The new estimated arrival time at Site PEAT-7C is early May 19.
Scientists began processing cores from Hole U1336B. Cores 1H-4H were split and described using the new core description application DESClogik. The lithologies were mainly nannofossil ooze and nannofossil ooze with foraminifera. Samples were also taken for moisture and density measurements and chemistry analyses.
Daily Science Report for 10 May 2009
LOCATION: En route to Site U1336 (PEAT-5C)
SCIENCE UPDATE: Scientists were introduced to the new sample data entry system (SampleMaster). Physical properties group ran practice core (320T Core 10) through all the track systems and performed thermal conductivity tests. Practice cores were split and scientists began describing using the new core description application DESClogik. Scientists continue to work on methods.
Daily Science Report for 9 May 2009
LOCATION: En route to Site U1336 (PEAT-5C)
SCIENCE UPDATE: Today's main activities include setting up the shipboard sampling plan and introductions to scientists' individual research plans. Discussions continue on prioritizing the operations plan. Lab teams continued learning instruments and preparing for practice core flow. The new dynamic positioning software system was tested on departure. Rig tours and introduction to coring and drilling were conducted for the scientists. The first boat and fire drill was held at 1300 h.
Daily Science Report for 8 May 2009
LOCATION: Pier 2, Honolulu Harbor, Honolulu, Hawaii (USA)
SCIENCE UPDATE: All scientists attended Captain's introduction and initial safety orientation. The 320 Chief scientists presented the preliminary results of Expedition 320 to PEAT II scientists. Lab teams continued learning instruments and methods. All technical staff received lab safety and marine mammal observer training. Afternoon was off as it was the last day on land for the next six weeks.
Daily Science Report for 7 May 2009
LOCATION: Pier 2, Honolulu Harbor, Honolulu, Hawaii (USA)
SCIENCE UPDATE: Scientists and technical staff began shipboard orientation and planning for PEAT II. Activities included personnel introductions, overview of PEAT science objectives by co-chief scientists, shipboard responsibilities and obligations, overall expedition reports and publications, introduction to information technology services (computers, servers, network, email, etc) lab safety and life onboard. Sedimentologists and paleontologists received an introduction to the new descriptive information system. Lab groups started orientation for lab instrumentation, methods, and safety. Lab tours were conducted for entire science party. Two education workshops were held for K-12 students and teachers.
Daily Science Report for 6 May 2009
LOCATION: Pier 2, Honolulu Harbor, Honolulu, Hawaii (USA)
SCIENCE UPDATE: PEAT II Expedition (321) Chief Scientists and USIO staff continue cross over with departing scientists and staff and start preparing orientation activities for oncoming scientists. PEAT II scientists moved onboard and began exploring the new labs and ship. Press events and ship tours continued throughout the day. A reception was held in the evening to celebrate the return of the newly rebuild JOIDES Resolution to international operations.
Daily Science Report for 5 May 2009
LOCATION: Pier 2, Honolulu Harbor, Honolulu, Hawaii (USA)
SCIENCE UPDATE: PEAT II Expedition (321) Chief Scientists and USIO staff began cross over with the departing scientists and staff to learn new labs, instruments, software, systems, and procedures. All oncoming freight was loaded onboard and stowed. A welcome reception was held at the Waikiki Aquarium for the NSF and IODP officials and PEAT scientists.