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 Post subject: Mineral Extinction
PostPosted: Fri Dec 06, 2019 11:58 pm 
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Abstract

‘Mineral evolution’ has attracted much attention in the last decade as a counterpart of the long-established biological concept, but is there a corresponding ‘mineral extinction’? We present new geochronological data from uranium-bearing secondary minerals and show that they are relatively recent, irrespective of the age of their primary uranium sources. The secondary species that make up much of the diversity of minerals appear to be ephemeral, and many may have vanished from the geological record without trace. Nevertheless, an ‘extinct’ mineral species can recur when physiochemical conditions are appropriate. This reversibility of ‘extinction’ highlights the limitations of the ‘evolution’ analogy. Mineral occurrence may be time-dependent but does not show the unique contingency between precursor and successor species that is characteristic of biological evolution.

Alfredo Petrov wrote:
Minerals requiring cold environments to survive, like ikaite, could become endangered if the climate heats up enough.

Photosynthesis may well have "killed" a lot of minerals unstable in the presence of oxygen, although of course the planet still has plenty of little anaerobic niche environments.




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 Post subject: Re: Mineral Extinction
PostPosted: Sun Dec 08, 2019 5:50 pm 
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Another post from the MSA thread
Marty Rutstein wrote:
so true- look at loss of exposures of ophiolte suite and serpentinized rocks in the Thetford Mines region- see the now "remediated" and closed Black Lake asbestos "mine" (quarry).
Now, the best place to study asbestos may well be in buildings undergoing asbestos abatement,


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