*OMAN'S PLANET OMEN*

HOW OMAN'S ROCKS could help save the planet.

THE ROCKS maybe capable of capturing a lot of carbon dioxide, but the challenge is doing it much faster than nature -

In huge amounts and at a low enough cost to make it more than a pipe dream.

Dr. Kelemen and his colleagues, including Juerg  Matter, a researcher from the University in Southampton in England who was involved in the project in Iceland, have some ideas.

One possibility, Dr. Kelemen said, would be to pairs of wells and pump with dissolved carbon dioxide into one of them.

As the water traveled through the rock formation, carbonate would form; when it reached the other well, the water - now depleted of carbon dioxide would be pumped out. The process could be repeated over and over.

There is a lot that is unknown such an approach, however. For one thing, while pumping water deep into the earth, where higher temperatures and pressures could make the process of mineralization go tens of thousands times faster, so much carbonate might flow that the water flow might stop.

''You must clog everything up, and it will all come to a screeching halt,'' Dr. Kelemen said.

Experiments and eventually pilot projects are needed to better understand and optimize this process.

Dr. Kelemen said, but some Omanis reluctance. As a result Dt. Kelemen and his colleagues have agreed not to do field experiments in Oman on the capture of carbon dioxide.

They may need to go elsewhere, like California, where the rocks are less accessible but the state government has set ambitious targets for reducing emissions and is open to new ways to meet them.

Dr. Kelemen and Dr. Aines have had preliminary discussions with California officials about the possibility experimenting there.

''We would certainly be willing and eager partners to help them with it,'' said David Bunn, director of the state's Department of Conservation.

Perhaps the simplest way to use rocks to capture carbon dioxide would be to quarry large amounts of them, grinding them into fine particles and spread them out to expose them to the air.

The material could be turned over from time to time to expose fresh surfaces, or perhaps air with a higher carbon dioxide concentration could be pumped into it to speed up the process.

The Honor and Serving of the latest Operational Research on carbon dioxide and emissions, to save the planet, continues to Part 3.