</bitter>

On a serious note, an alike proposal has been made by one of the more controversial professors (Schuiling) of my former university. Last year, if I recall, he went to Turkey to see how feasible it would be to create peridotite pebble beaches - beaches and saline water would be a good spot to enhance chemical weathering. Don't know how that ended, but I'll find out during my Christmas break - a friend of mine came along. Schuiling's name pops up here and there on the web.

In praise of olivine...

But the process is neither simple nor straightforward. This is why "seeding" the ocean with iron oxide to cause a plankton bloom is an uncertain longtime means of capturing CO2.  Limestone deposits are often found in alteration with shale deposits.  That would seem to indicate that the process turns on and off.  That, in turn, might enable some insight into how to cultivate this process on a geologic scale.

Perhaps the melting of polar ice caps will result in the creation of new shallow seas which will turn this process back on.  That solution is likely to be rather slow from a human perspective, but that might not matter---in the long run.  Nomad should be able to amplify and/or correct this comment.

As the Dutch said while fighting the Spanish: "It is not necessary to have hope in order to persevere."