-
128
The Last Resource
picture of the continental shelf around the United Kingdom. Dr
John S. Tooms of London University has made the point that an
obvious place to start detailed mapping and surveying is where rich
deposits of minerals are known to occur on the adjacent land. But
this is only the start, and the plain fact is that more money must be
spent on exploratory work if the mineral potential of the seas is to
be realized. Of course, both British and American agencies are
‘
spending or considering investing large sums of money in marine
»
science, but this expenditure is relatively small when compared
with the money being lavished on improving geological knowledge
of already well prospected land areas.
Generally, the principal objection to exploiting mineral resources
is that their content of valuable mineral, although enormous on a
world scale, is not as great as deposits at present being worked on the
'
land. But the nal question must always he ‘can a particular mineral
be supplied more cheaply by turning to the sea?’ And since the
'
nal cost depends on many factors other than the richness of the
source, some surprising results can occur. The
of
_
magnesium from sea—water is a case in point. The concentration of
_
this mineral in sea—water is only 1/300th that of land deposits, but
other technical reasons make its removal from sea—water more
economic than mining the land deposits: the magnesium content of
the sea is extremely uniform; the materials involved—sea—water and
magnesium carbonate slurry—can be easily moved; and the process
-
_
is more or less continuous. These three qualities all help to make the
,
extraction process a candidate for automation—fresh ‘lean ore’ is
brought continuously by tidal currents to the plant, the handling
costs are very low and, nally, the end product builds up continuously to make distribution predictable and convenient.
.
Some scientists have suggested that the development of desalina—
tion on a grand scale might be another factor which could tip the
scales in favour of extracting other dissolved minerals. They argùe
-
that the concentrated brine left after the removal of the fresh water
could arrive at possible extraction plants already slightly warm,
which might improve reactivity of its chemical content andwhich
at a slight pressure would help in ‘pushing’ it through the plant.
John Moro has worked out the possible yield if, in a few decades’
time, there is a coastal population of some 100 million people each
_
consuming 100,000 gallons 0f water annually for domestic and in—
dustrial purposes, all of which comes from the sea via a process
128
The Last Resource
picture of the continental shelf around the United Kingdom. Dr
John S. Tooms of London University has made the point that an
obvious place to start detailed mapping and surveying is where rich
deposits of minerals are known to occur on the adjacent land. But
this is only the start, and the plain fact is that more money must be
spent on exploratory work if the mineral potential of the seas is to
be realized. Of course, both British and American agencies are
‘
spending or considering investing large sums of money in marine
»
science, but this expenditure is relatively small when compared
with the money being lavished on improving geological knowledge
of already well prospected land areas.
Generally, the principal objection to exploiting mineral resources
is that their content of valuable mineral, although enormous on a
world scale, is not as great as deposits at present being worked on the
'
land. But the nal question must always he ‘can a particular mineral
be supplied more cheaply by turning to the sea?’ And since the
'
nal cost depends on many factors other than the richness of the
source, some surprising results can occur. The
of
_
magnesium from sea—water is a case in point. The concentration of
_
this mineral in sea—water is only 1/300th that of land deposits, but
other technical reasons make its removal from sea—water more
economic than mining the land deposits: the magnesium content of
the sea is extremely uniform; the materials involved—sea—water and
magnesium carbonate slurry—can be easily moved; and the process
-
_
is more or less continuous. These three qualities all help to make the
,
extraction process a candidate for automation—fresh ‘lean ore’ is
brought continuously by tidal currents to the plant, the handling
costs are very low and, nally, the end product builds up continuously to make distribution predictable and convenient.
.
Some scientists have suggested that the development of desalina—
tion on a grand scale might be another factor which could tip the
scales in favour of extracting other dissolved minerals. They argùe
-
that the concentrated brine left after the removal of the fresh water
could arrive at possible extraction plants already slightly warm,
which might improve reactivity of its chemical content andwhich
at a slight pressure would help in ‘pushing’ it through the plant.
John Moro has worked out the possible yield if, in a few decades’
time, there is a coastal population of some 100 million people each
_
consuming 100,000 gallons 0f water annually for domestic and in—
dustrial purposes, all of which comes from the sea via a process