IODP Expedition 321
Pacific Equatorial Age Transect 2
Daily Science Report for 22 June 2009
LOCATION: In transit and arrive at 10th Avenue Marine Terminal, San Diego Harbor, San Diego, CA.
SCIENCE UPDATE: Expedition summary completed. Shipments being prepared, lab cleaning finished. After 7.3 days of transit from Site U1338, Expedition 321 officially concluded at 1715 hr with the first line ashore at the 10th Avenue Marine Terminal, San Diego Harbor. Estimated departure time to Juan de Fuca Site 1301 is 0700 on June 24.
Daily Science Report for 21 June 2009
LOCATION: In transit to San Diego, CA. At 2400 h, 30° 57.4' North, 117° 26.6' West
SCIENCE UPDATE: All site reports finished. Expedition Summary being produced. Backups underway, shipments being prepared, lab cleaning started.
Daily Science Report for 20 June 2009
LOCATION: In transit to San Diego, CA. At 2400 h, 27° 27.1' North, 117° 39.3' West
SCIENCE UPDATE: Site U1338 reports are completed. Expedition summary being produced. Technical staff began preparing cores and other shipment going off in San Diego. Celebrated end of the expedition and the beginning of summer with summer solstice dance party.
Daily Science Report for 19 June 2009
LOCATION: In transit to San Diego, CA. At 2400 h, 23° 7.1' North, 117° 54.3' West
SCIENCE UPDATE: Site U1338 reports nearly finished. Expedition summary being produced. Technical staff began preparing cores and other shipment going off in San Diego.
Daily Science Report for 18 June 2009
LOCATION: In transit to San Diego, CA. At 2400 h, 18° 34.3' North, 118° 9.5' West
SCIENCE UPDATE: Expedition Summary being produced. Post-cruise research planning meetings continue. Group photo was taken after the last fire and boat drill for this expedition.
Daily Science Report for 17 June 2009
LOCATION: In transit to San Diego, CA. At 2400 h, 14° 8.4' North, 118° 11.6' West
SCIENCE UPDATE: Science meeting for Site U1338 was held. Site reports are being finalized. Post-cruise research planning meetings continue.
Daily Science Report for 16 June 2009
LOCATION: In transit to San Diego, CA. At 2400 h, 9° 49.5' North, 118° 13.9' West
SCIENCE UPDATE: All cores from Site U1338 have been processed. Scientists continue to work on site reports. Post-cruise research planning meetings continue.
Daily Science Report for 15 June 2009
LOCATION: In transit to San Diego, CA. At 2400 h, 5° 20.5' North, 118° 4.0' West
SCIENCE UPDATE: Cores U13338C-40H through 47H were split, imaged and described. Cores are predominantly nannofossil ooze with very low amounts of radiolarians and diatoms. The transition from light greenish grays to pale yellows occurs in Core 44H. No basalt was recovered at the bottom of Hole U1338C. Cores are moderately bioturbated with mottling only visible in darker intervals. Site U1338 has been completely described. Paleomagnetic measurements continue on Hole U1338C cores. Scientists continue to work on site reports. Science meeting for Site U1338 is scheduled for tomorrow.
Daily Science Report for 14 June 2009
LOCATION: At Site U1338 (PEAT 8D), 2° 30.4' North, 117° 58.1' West
SCIENCE UPDATE: APC cores U1338C-40H through 47H advanced from 354.4 to 414.4 m DSF, setting a new record for the deepest APC. Cores U1338C-40H through 47H recovered 62.65 m (104.4%). Offset ship 20m west of Hole U1338C and spud Hole U1338D. The primary purpose of this hole is to recover few cores that can be used to practice core flow on Expedition 323. Three APC cores (U1338D-1H through 3H) advanced from 0 to 23.9 m DSF, recovered 24.79 m (103.7%).
Cores U13338C-25H through 39H were split, imaged and described. Cores 25H through 32H are predominantly nannofossil ooze containing minor but varying amounts of diatoms, radiolarians, and calcite components. Cores 33H-39H were 90% nannofossil with very low amounts of radiolarians and diatoms. Cores are intensely bioturbated and mottled.
Daily Science Report for 13 June 2009
LOCATION: At Site U1338 (PEAT 8D), 2° 30.4' North, 117° 58.1' West
SCIENCE UPDATE: APC cores U1338C-25H through 39H advanced from 218.3 to 354.4 m DSF, recovered 140.67 m (103.4%).
Scientists continue to process cores from Hole U1338C. Cores U13338C-11H through 24H were split, imaged and described. Sediments are predominantly nannofossil ooze containing minor but varying amounts of diatoms, radiolarians, and calcite components. Cores are intensely bioturbated and mottled, with cm- to dm-scale diagenetic color banding common throughout. Micropaleontology lab continues to process samples and refine biostratigraphic datums.
Daily Science Report for 12 June 2009
LOCATION: At Hole U1338C (PEAT 8D), 2° 30.4' North, 117° 58.1' West
SCIENCE UPDATE: APC cores U1338C-4H through 24H advanced from 22.8 to 218.3 m DSF, recovered 205.4 m (105.0%).
Cores U1338C-1H through 11H were split, imaged and described. Cores are similar to those described in Holes A and B. Sediments are dominated by nannofossil ooze with meter scale intervals of increased diatom content. Cores are intensely bioturbated and mottled, with cm- to dm-scale diagenetic color banding common in Cores 5H-11H.
Daily Science Report for 11 June 2009
LOCATION: At Site U1338 (PEAT 8D), 2° 30.471' North, 117° 58.162' West
SCIENCE UPDATE: Downhole logging continued at Hole U1338B. The FMS-sonic tool reached the surface at 0120 h and was rigged down by 0215 h. The third and final toolstring, the VSI (Versatile Seismic Imager), was rigged up and run into the hole ~0310 h. Mammal watch started at first light and the airguns were put into the water at 0645h. Data were acquired at 14 stations (~15 m apart) between 4623 and 4397 m WRF. Downhole logging was completed at 1317 h.
Offset 20 m west of Hole U1338B and started coring Hole U1338C to cover gaps between cores in previous holes. APC cores U1338C-1H through 3H advanced from 0 to 22.8 m DSF, recovered 23.8 m (104.4%). All cores from Hole U1338B have been split and described. Geochemical analyses and paleomagnetic measurements continue.
Daily Science Report for 10 June 2009
LOCATION: At Site U1338 (PEAT 8D), 2° 30.471' North, 117° 58.162' West
SCIENCE UPDATE: Cores U1338B-30H through -43X were split, imaged and described. Sediments are predominantly nannofossil ooze turning to nannofossil chalk and calcareous nannofossil chalk in 42H. Thin intervals of increased diatom abundance (Thalassiothrix spp.) alternate with the main lithology at meter-scales. Angular chert fragments were recovered in Core U1338B-31H. Color changes sharply from greenish gray to pale yellow hues in Section U1338B-42H-6. Cores 44X-45X had abundant mm-scale oxide nodules throughout. Pale yellow to light yellowish brown fractured nannofossil chalks made up the sediments above basement (Cores 44X-45X). The core catcher of 45X had three 2-3 cm pieces of weathered aphanitic basalt.
Logging activities continued through out the day. The first tool string, the modified Triple Combo (Gamma Ray, Density and Resistivity), acquired one downlog, a partial uplog and a full pass. A significant 'tight spot'/restriction was encountered ~50 m beneath the bottom of the pipe, and a second pass was not attempted. Pipe was lowered to 4353 m DRF for the second toolstring, the FMS (imaging)-sonic, to avoid the restricted area. One downlog and two full passes were acquired. Logging with the FMS-sonic was completed at 2100 h, and the toolstring started its journey back to the rig floor for rig down.
Daily Science Report for 9 June 2009
LOCATION: At Site U1338 (PEAT 8D), 2° 30.471' North, 117° 58.162' West
SCIENCE UPDATE: APC cores U1338B-38H through 42H advanced from 339.9 to 387.4 m DSF, recovered 49.79 m (104.8%). The APC cored interval from Hole U1338B represents the second deepest APC cored depth in ODP and IODP history. XCB cores U1338A-43X through 45X advanced from 387.4 to 416.1 m DSF, recovered 16.62 m (57.9%). The basement was recovered in Core 45X.
Cores U1338B-17H through 29H were imaged and described. Sediments are dominated by nannofossil ooze with meter scale intervals of increased diatom content. Cores are intensely bioturbated and mottled, with cm- to dm-scale diagenetic color banding common throughout. Color ranges from whites to pale yellows. The micropaleontology lab continues to process samples and refine biostratigraphic datums. Assemblages of planktonic and benthic foraminifers in Hole U1338A are diverse. Logging activities began with the triple combo tool string upon completion of coring at Hole U1338B.
Daily Science Report for 8 June 2009
LOCATION: At Site U1338 (PEAT 8D), 2° 30.471' North, 117° 58.162' West
SCIENCE UPDATE: APC cores U1338B-23H through 37H advanced from 207.1 to 339.9 m DSF, recovered 135.2 m (103.7%). Cored intervals in this second hole are targeting gaps in core recovery from the first hole. Initial results indicate we have recovered a nearly complete section down to ~300 m DSF.
Cores U1338B-1H through 16H were imaged and described. Similar lithological variations were found as described for Hole U1338A with sediments dominated by nannofossil ooze alternating with lithologies showing slightly increased diatom content. Intense mottling of all lithologies is present and light gray/pale green diagenetic color bands are common. Whole round fast-track, multisensor track and natural gamma measurements continue on cores from Hole U1338B.
Daily Science Report for 7 June 2009
LOCATION: At Site U1338 (PEAT 8D), 2° 30.471' North, 117° 58.162' West
SCIENCE UPDATE: APC cores U1338B-2H through 22H advanced from 7.6 to 207.1 m DSF, recovered 208.0 m (104.3%). Cores U1338A-29X through 44X were split, imaged and described. Sediments consist of nannofossil chalk with minor components of diatoms and radiolarians in thin intervals. A strong green to yellow color change is found in Core U1338A-41X-CC. At the base of 44X-CC we recovered 3 small (cm-sized) fragments of weathered aphanitic basalt. Sediments accumulated above basement were dated at 17.7 Ma. Whole round fast-track, multisensor track and natural gamma measurements continue on cores from Hole U1338B.
Daily Science Report for 6 June 2009
LOCATION: At Site U1338 (PEAT 8D), 2° 30.471' North, 117° 58.162' West
SCIENCE UPDATE: XCB cores U1338A-32X through 44X advanced from 288.1 to 410.0 m DSF, recovered 78.4 m (64.3%). The basement was recovered in Core 44X and the age of the basement is close to 17.7 Ma. Cores U1338A-15H through 29X were imaged and described. Sediments are predominantly nannofossil ooze with cyclic alternations of thin intervals containing slightly more biosiliceous components. Thin diagenetic color banding and fine-grained pyrite, mainly filling burrow structures, occurs throughout the entire interval. Core U1338A-15H contained ~1.5 m of laminated diatom ooze. Core U1338A-29X did not recover sediment except for a large concretion of dolomite in the core catcher. Whole round fast-track, multisensor track and natural gamma measurements were completed on Cores U1338A-15H through 33X. Moisture and density (MAD) measurements were completed up to Core U1338A-29X. Geochemical analyses continue on interstitial water and bulk sediment samples from Hole U1338A.
Offset 20 m west of Hole U1338A and started coring Hole U1338B to cover gaps between cores in the first hole. APC core U1338B-1H advanced from 0 to 7.6 m DSF, recovered 7.6 m (100.0%).
Daily Science Report for 5 June 2009
LOCATION: At Site U1338 (PEAT 8D), 2° 30.471' North, 117° 58.162' West
SCIENCE UPDATE: APC cores U1338A-12H through 26H advanced from 97.7 to 240.2 m DSF, recovered 149.1 m (104.6%). XCB cores U1338A-27X through 31X advanced from 240.2 to 288.1 m DSF, recovered 16.5 m (34.5%). The low recovery (0-1%) on cores 28X, 30X, and 31X is likely caused by the diatom mats. Cores U1338A-4H through 14H have been opened, imaged and described. Sediment lithologies are predominantly nannofossil ooze with a few thin intervals of increased diatom abundance. Intensive mottling and thin color banding occurs throughout most of this interval. The Pliocene/Pleistocene boundary based on planktic foram and calcareous nannofossils was found within Core 3H (18.25-22.16 m CSF-A) and the Miocene/Pliocene boundary between Cores 8H and 9H (64.51-75.15 m CSF-A). The APCT-3 temperature tool was deployed with Cores 5H, 7H, 9H, 11H and 13H and the estimated thermal gradient is 36.5°C/km.
Daily Science Report for 4 June 2009
LOCATION: At Site U1338 (PEAT 8D), 2° 30.471' North, 117° 58.162' West
SCIENCE UPDATE: Hole U1338A was spudded at 1155 hr establishing a seafloor depth of 4210.8 m DRF. First APC core arrived on deck at 1220 hr. Cores U1338A-1H through 11H advanced from 0 to 97.7 m DSF, recovered 101.9 m (104%).
The upper 11 cores are Pleistocene–late Miocene. Cores U1338A-1H through 3H were opened, imaged and described. Sediments are predominantly nannofossil ooze containing varying amounts of minor components (radiolarians, diatoms and calcite). Colors vary from dark grayish brown to pale brown (Cores 1H and 2H) and light greenish gray (beginning in Core 3H).
Daily Science Report for 3 June 2009
LOCATION: In transit to Site PEAT-8D (U1338)
SCIENCE UPDATE: Scientists continue to process cores from Hole U1337D. Cores U1337D-36X through 49X have been imaged and described. Lithological descriptions are consistent with same intervals recovered in previous holes. Major lithologies include nannofossil chalk, nannofossil chalk with radiolarians and nannofossil chalk with diatoms. Core U1337D-49X contained numerous small (mm) grains of black opaque manganese oxides and aphanitic basalt. Basalt shows 1-2 mm vesicular texture along cut surface. Thin vein of calcite fills fracture. Basalt also shows limonite alteration rind through cut surface. A pre-site science meeting was held to review science objectives for Site PEAT-8D.
Daily Science Report for 2 June 2009
LOCATION: At Hole U1337D (PEAT-7C) and start transit to Site PEAT-8D (U1338)
SCIENCE UPDATE: XCB Cores U1337C-46X through 49X advanced from 410.1 to 442.9 m DSF, 21.0 m recovered (64.1%). Basement was recovered in Core 49X. Cores U1337D-15H through 35X split, imaged and described. Sediments consist of cyclic alternations between mixed lithologies composed of nannofossil oozes/chalks and biosiliceous components. More than 18 m of laminated diatom ooze intervals was recovered in total from Hole U1337D. Scientists continue to work on Site U1337 science report. Pre spud meeting was held to review operations and logging plan for Site PEAT 8D (U1338).
Daily Science Report for 1 June 2009
LOCATION: At Hole U1337D (PEAT-7C), 3° 50.0' North, 123° 12.3' West
SCIENCE UPDATE: APC Cores U1337D-28H through 30H advanced from 241.4 to 267.0 m DSF, 28.4 m recovered (111.0%). XCB Cores U1337C-31X through 45X advanced from 267.0 to 410.1 m DSF, 137.7 m recovered (96.2%).
Cores U1337D-4H through 20H have been imaged and described. Lithological descriptions are consistent with same intervals recovered in previous holes and consist of cyclic alternations between main lithologies that reflect varying amounts of nannofossils, radiolarian and diatoms. Sediments are intensely bioturbated and thin color bands and color lamina overprint most of the lithologies. Several large dolomite concretions were encountered. Core U1337D-18H contains the first appearance of laminated diatom ooze interbedded with nannofossil ooze and diatom nannofossil ooze. These laminated "diatom mat" intervals contain abundant Thalassiothrix group diatoms. Occasional thin lamina (mm) of porcellanite also occurs within these units. Cores U1337D-1H through 25H have completed with whole round fast-track, multisensor track data and with natural gamma measurements.