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doi:10.2204/iodp.proc.320321.216.2014

Site locations

The three sites in this data report, along with Site U1338, contain the major Neogene sediment sections for the PEAT equatorial Pacific megasplice. The sites are located between 7°42′N and 3°50′N (Fig. F1).

Site U1335

Site U1335 (5°18.735′N, 126°17.002′W; 4327.5 m water depth) is on ~26 Ma crust halfway between Site U1336, ~340 km to the northwest, and Site U1337, ~390 km to the southeast, and ~250 km south of the Clipperton Fracture Zone (see the “Site U1335” chapter [Expedition 320/321 Scientists, 2010b]). This site is located on a broad plateau that parallels the Clipperton Fracture Zone and is within north-northeast–trending abyssal hill topography. Drilling recovered 417 m of biogenic sediment above basement. Here we report XRF scan data at 2.5 cm spacing for only part of the Site U1335 splice, from 0 to 302.66 mcd, covering the time span between ~0 and 20 Ma. Figure F2 shows CaCO₃ normalized median-squared (NMS) data from 0 to 302.66 mcd.

Site U1336

Site U1336 (7°42.067′N, 128°15.253′W; 4286 m water depth) is on 32 Ma crust, ~340 km northwest of Site U1335 (see the “Site U1336” chapter [Expedition 320/321 Scientists, 2010c]). The site is ~30 km north of the center of the Clipperton Fracture Zone on a local high that is draped with ~300 m of sediment cover. The abyssal hills are oriented slightly west of due north. Coring revealed a hiatus at the top of the section to ~12 Ma. Here we report XRF scan data at 2.5 cm spacing for only part of the Site U1336 splice, from 0 to 142.46 mcd. The Site U1336 scanning covers an age span roughly from 12 Ma (the top of the sediment column) to 22 Ma. The splice used for this project is a revised version of the shipboard splice based on Wilkens et al. (2013). The revisions are due primarily to a poorly recovered interval at roughly 152 mcd that resulted in cores being appended to one another below this depth, rather than being tied together. The appended interval is below the scanned interval. Figure F3 shows CaCO₃ NMS data from 0 to 142.46 mcd.

Site U1337

Site U1337 (3°50.009′N, 123°12.352′W; 4463 m water depth) is on ~24 Ma crust between the Galapagos and Clipperton Fracture Zones (see the “Site U1337” chapter [Expedition 320/321 Scientists, 2010d]). The site is ~390 km southeast of Site U1335, on a plateau between higher topography south of the site and a ridge to the north. Here we report XRF scan data for the entire Site U1337 splice, from 0 to 491.62 mcd, covering the entire spliced section. The upper sediment column (0–102.45 cm along the splice) was scanned at 5 cm intervals in order to tie to the high-resolution scan (0.5 cm interval) scanned by K. Iijima (unpubl. data). The remainder of the sediment column was scanned at 2.5 cm spacing. The splice we use has some changes from the original shipboard splice due to core disturbance, especially at greater depth, and trouble with correlating the four cores that make up the Site U1337 splice. The splice is the revised splice reported in Wilkens et al. (2013). A depth of close to 490 mcd was reached with only three gaps from the four holes. Figure F4 shows CaCO₃ NMS from 0 to 475 mcd for Site U1337.

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