(Table 2) Location, age of accompanied sediments, chemical and Sr isotopic compositions of manganese nodules in DSDP/ODP cores

• Main Authors: Ito, Takashi, Usui, Akira, Kajiwara, Yoshimichi, Nakano, Takanori
• Format: Dataset
• Language: English
• Published: PANGAEA 1998
• Subjects: 108-661A; 114-699A; 122-760A; 15-150; 32-303; 36-328; 5-37; 62-464; 81-554A; 86-578; 93-603B; Caribbean Sea/BASIN; Comment; Deep Sea Drilling Project; DEPTH; sediment/rock; DRILL; Drilling/drill rig; DSDP; DSDP/ODP/IODP sample designation; Epoch; Event label; Glomar Challenger; ICP-OES; Inductively coupled plasma - optical emission spectrometry; Interval comments; Iron; Joides Resolution; Latitude of event; Leg108; Leg114; Leg122; Leg15; Leg32; Leg36; Leg5; Leg62; Leg81; Leg86; Leg93; Longitude of event; Manganese; Mass spectrometer Finnigan MAT 262 RPQ Plus; Minerals; North Atlantic/PLATEAU; North Atlantic Ocean; North Pacific; North Pacific/BASIN; North Pacific/CONT RISE; North Pacific/HILL; Antarctic; Pacific; Antarc*; North Atlantic
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.696424; https://doi.org/10.1594/PANGAEA.696424

Strontium isotopic compositions of acetic acid (HOAc) leachate fractions of eight manganese oxide deposits from the modern seafloor, and of twenty-one buried manganese nodules from Cretaceous to Recent sediments in DSDP/ODP cores were measured. ratios of HOAc leachates in all modern seafloor manganese oxides of various origins are identical with present seawater. The ratios of the HOAc leachates of buried nodules from DSDP/ODP cores are significantly lower than those of nodules from the modern seafloor and are mostly identical with coeval seawater values estimated from the age of associated sediments. It is suggested that the buried nodules in DSDP/ODP cores are not artifacts transported from the present seafloor during the drilling process, but are in situ fossil deposits from the past deep-sea floor during Cretaceous to Quaternary periods. The formation of deep-sea fossil nodules prior to the formation of Antarctic Bottom Water (AABW) indicates that the circulation of oxygenated deep seawaters have activately deposited manganese oxides since the Eocene Epoch, or earlier.