Sediment Trap Data from the CARIACO Ocean Time Series (1995-2010)

The Cariaco Basin is a 1400-m-deep depression approximately 160 km long by 70 km wide located off the central Venezuelan coast . It is connected to the Atlantic Ocean by a sill ~100-m-deep, and two slightly deeper channels that breech it; Canal Centinela (146-m-deep) and Canal de la Tortuge (135-m-deep). High surface production rates and restricted circulation result in anoxic waters below ca. 275 m. The depth of the oxycline varies between 250 and 320 m and is independent of density. Rather, fluctuations in oxycline depth appear to be due to lateral intrusions of Caribbean Sea water that are linked to eddies along the continental shelf. A mooring with five sediment traps (Z, A-D) is located in the eastern Cariaco Basin. Traps A-D have been in place since November 1995. Trap A is located in oxic waters at 226 ± 6 m. Trap B is located at 407 ± 3 m and Trap D is located at 1205 ± 3 m. Trap C was located at a depth of 880 ± 2 m from Jan. 1996 to Nov. 2000, and was moved to 807 ± 2 m in Nov. 2000. A fifth trap, Z, was added in November 2003 at 110 m for the first 6 months, and at 150 m thereafter. All five sediment traps are coneshaped with a 0.5 m**2 opening that is covered with a baffle top to reduce turbulence. The mooring is deployed for six-month intervals and each sample collection cup is filled with a buffered 3.2% formalin solution as a preservative for the accumulating organic matter. The cups are numbered 1-13, with cup 1 collecting for the two-week interval immediately following deployment, and cup 13 collecting for the 2 weeks immediately before recovery.

Paleomagnetic characterization and age of several ODP Leg 198 sites, Shatsky Rise

Shatsky Rise, a medium-sized large igneous province in the west Central Pacific Ocean, has three main topographic highs that preserve a thick sedimentary record from Cretaceous through Cenozoic. During Ocean Drilling Program (ODP) Leg 198 to Shatsky Rise, a total of ~768 m of late Miocene-Holocene sediments was recovered from six sites. Sites 1207 and 1208 were drilled on the Northern and Central Highs, respectively, and yielded expanded late Miocene-Holocene sequences. Sites 1209, 1210, 1211, and 1212 were drilled on the Southern High and yielded shorter sequences of similar age. Clearly interpretable magnetic stratigraphies were obtained from all sites using the shipboard pass-through magnetometer. These results were augmented using discrete sample cubes (7 cm**3) collected shipboard and measured postcruise. Miocene age sediments are separated by a hiatus from Oligocene, Eocene, and Cretaceous age sediments beneath. An astrochronological age model was developed for the six sites based on cycles observed in reflectance data, measured shipboard. This age model is in good agreement with published astrochronological polarity chron ages in the 1 to 6 Ma interval.