『Abstract
Distribution of the major and trace elements in ferromanganese
nodules, which are buried or exposed on the seafloor, and in host
sediments was studied in ten concretion/sediment pairs by various
physical and chemical methods. It has been established that, in
addition to Fe and Mn, a limited number of the major and trace
elements (P, Ca, Sr, Ba, Mo, Co, Zn, Ni, As, Pb, Sb, Tl, U, W,
Y, and Ga included) is accumulated with a variable degree of intensity
(relative to sediments) in the concretions. as compared to host
sediments, the maximal content of Mn in concretions is 100 times
higher, whereas maximal contents of all other elements listed
above vary from more than one to 10-20 times. Manganese and, to
a lesser extent, Ba and Sr are concentrated in the buried concretions.
Other elements are primarily concentrated in concretions exposed
on the seafloor. The occurrence mode of concretions and compositional
data on interstitial water suggest that metals in the concretions
were derived from seawater and suspended particulates, in addition
to sediments. Burial of concretions in the sediment pile is accompanied
by the alteration of their composition, accumulation of Mn (relative
to Fe), and loss of several associated metals.』
(Introduction)
Materials and methods
Distribution, morphology, and mineral composition of concretions
Rock-forming and ore elements in concretions and sediments
Trace elements in concretions and sediments
Sedimentation settings, growth rate of concretions, and issues
of their genesis
Acknowledgments
References