Marine manganese nodules, those strange, fist-sized metallic clusters that cover about 30% of the ocean floor, have been known for over a hundred years. At first glance they appear very fresh; yet, according to paleontological and radiometric dating methods, the nodules are supposedly multi-millions of years old, the result of extremely slow growth rates of just millimetres per million years. However, actual observations have revealed that nodules can grow in excess of 20 cm within hundreds of years, a growth rate several orders of magnitude faster. In addition, nodules are found only at the top of the ocean floor, with the greatest density within the first 5 m of sediment and decreasing in size at greater depths. This contradicts the idea that ocean sediment accumulated gradually and continuously over millions of years. Rather it suggests a period of rapid sedimentation that has subsequently waned, a scenario that is consistent with the events of Noah’s Flood.

First discovered in 1873 during a cruise of the HMS Challenger, marine Manganese nodules (MNs) have increasingly courted the attention of the geological community. As well as the obvious resource potential, MNs have also been studied for their palaeoceanographic information due to their assumed slow growth rates. MNs are found at “almost all depths and latitudes in all the oceans of the world, as well as in some lakes … The nodules are especially common in the Pacific Ocean … where it is estimated that they cover approximately 10–30% of the deep ocean floor.”1

MNs are teeming with all types of metals, but five are significant and the target of mining prospectors: Mn, Fe, Ni, Cu, and Co, with manganese being the most abundant, having a mean of about 24% (hence the name Manganese Nodule).2 MNs come in all different shapes and sizes; Vineesh et al. concur: “Large variation in morphological types of nodules are found in the CIB [Central Indian Basin] with spherical, oblong, triangular rounded, sub-rounded or irregular shapes being most common.”3 They also make some interesting observations as to nodule nuclei, “The most common nucleus is altered basalt, while pumice, shark teeth, clay and older nodule nuclei are also present.”3

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