Minerals Report - International Seabed Authority

asal diameter at 1,600 m water depth) range up to 230 ppm gold, with an
average of 26 ppm gold, for the 40 samples analysed.
On likely deposits that may attract contractors for exploration and
mining, Professor Herzig stated that of the more than 100 sites of
hydrothermal mineralisation currently known at the modern seafloor, only
about 10 deposits may have sufficient size and grade to be considered for
future mining, although information on the thickness of most of these
deposits unknown. He identified these potential mine sites as the Atlantis II
Deep in the Red Sea, the sites at Middle Valley, the Explorer Ridge, the
Galapagos Rift, and the East Pacific Rise at 13 o N in the Pacific Ocean, the TAG
hydrothermal field in the Atlantic Ocean; as well as the Manus Basin, the Lau
Basin, the Okinawa Trough, and the North Fiji Basin in the western and
south-western Pacific ocean. He noted that all of these potential mine sites,
except for the sites at the East Pacific Rise at 13°N and TAG hydrothermal
field, are located in the exclusive economic zones of coastal states (Saudi
Arabia, Sudan, Canada, Ecuador, Papua New Guinea, Tonga, Japan, and Fiji).
With respect to the future development of seafloor massive sulphides,
Professor Herzig stated that if drilling proves that high-grade gold
mineralisation is widespread and abundant, Conical Seamount would become
the first marine gold deposit to be mined. In addition to the high
concentrations of gold in this deposit, Professor Herzig pointed to the
advantages of this site, such as its occurrence at comparatively shallow depth
(1,050 m), its location within the territorial zone of Papua New Guinea, the
fact that it is inactive (no disturbance of fauna) and almost sediment-free (no
plume development due to mining activities), and that a processing plant is
available on Lihir which is only 25km away. He suggested that such an event
would have significant impact on the future development of seafloor mining
for base and precious metals. Considering all circumstances, he concluded
that seafloor polymetallic massive sulphides mining is likely to take place in
the current decade. In this regard, he reminded participants that the offshore
oil industry was launched only about 35 years ago, and there is no doubt in
his mind that this has been a very successful endeavour.
INTERNATIONAL SEABED AUTHORITY 28