Origin of Metalliferous Sediments from the Pacific Ocean

Abstract

Research Article| October 01, 1973 Origin of Metalliferous Sediments from the Pacific Ocean JACK DYMOND; JACK DYMOND 1School of Oceanography, Oregon State University, Corvallis, Oregon 97331 Search for other works by this author on: GSW Google Scholar JOHN B. CORLISS; JOHN B. CORLISS 1School of Oceanography, Oregon State University, Corvallis, Oregon 97331 Search for other works by this author on: GSW Google Scholar G. ROSS HEATH; G. ROSS HEATH 1School of Oceanography, Oregon State University, Corvallis, Oregon 97331 Search for other works by this author on: GSW Google Scholar CYRUS W. FIELD; CYRUS W. FIELD 2Department of Geology, Oregon State University, Corvallis, Oregon 97331 Search for other works by this author on: GSW Google Scholar E. JULIUS DASCH; E. JULIUS DASCH 2Department of Geology, Oregon State University, Corvallis, Oregon 97331 Search for other works by this author on: GSW Google Scholar H. HERBERT VEEH H. HERBERT VEEH 3Hawaii Institute of Geophysics, University of Hawaii, Honolulu, Hawaii 96822 Search for other works by this author on: GSW Google Scholar GSA Bulletin (1973) 84 (10): 3355–3372. https://doi.org/10.1130/0016-7606(1973)84<3355:OOMSFT>2.0.CO;2 Article history first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation JACK DYMOND, JOHN B. CORLISS, G. ROSS HEATH, CYRUS W. FIELD, E. JULIUS DASCH, H. HERBERT VEEH; Origin of Metalliferous Sediments from the Pacific Ocean. GSA Bulletin 1973;; 84 (10): 3355–3372. doi: https://doi.org/10.1130/0016-7606(1973)84<3355:OOMSFT>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract Sediments from near the basement of a number of Deep Sea Drilling Project (DSDP) sites, from the Bauer Deep, and from the East Pacific Rise have unusually high transition metal-to-aluminum ratios. Similarities in the chemical, isotopic, and mineralogical compositions of these deposits point to a common origin. All the sediments studied have rare-earth-element (REE) patterns strongly resembling the pattern of sea water, implying either that the REE's were coprecipitated with ferromanganese hydroxyoxides (hydroxyoxides denote a mixture of unspecified hydrated oxides and hydroxides), or that they are incorporated in small concentrations of phosphatic fish debris found in all samples. Oxygen isotopic data indicate that the metalliferous sediments are in isotopic equilibrium with sea water and are composed of varying mixtures of two end-member phases with different oxygen isotopic compositions: an iron-manganese hydroxyoxide and an iron-rich montmorillonite. A low-temperature origin for the sediments is supported by mineralogical analyses by x-ray diffraction which show that goethite, iron-rich montmorillonite, and various manganese hydroxyoxides are the dominant phases present. Sr87/Sr86 ratios for the DSDP sediments are indistinguishable from the Sr87/Sr86 ratio in modern sea water. Since these sediments were formed 30 to 90 m.y. ago, when sea water had a lower Sr87/Sr86 value, the strontium in the poorly crystalline hydroxyoxides must be exchanging with interstitial water in open contact with sea water. In contrast, uranium isotopic data indicate that the metalliferous sediments have formed a closed system for this element. The sulfur isotopic compositions suggest that sea-water sulfur dominates these sediments with little or no contribution of magmatic or bacteriologically reduced sulfur. In contrast, ratios of lead isotopes in the metalliferous deposits resemble values for oceanic tholeiite basalt, but are quite different from ratios found in authigenic marine manganese nodules. Thus, lead in the metalliferous sediments appears to be of magmatic origin.The combined mineralogical, isotopic, and chemical data for these sediments suggest that they formed from hydrothermal solutions generated by the interaction of sea water with newly formed basalt crust at mid-ocean ridges. The crystallization of solid phases took place at low temperatures and was strongly influenced by sea water, which was the source for some of the elements found in the sediments. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.