Thanks for bringing this up Andrew... Greg, to follow up on your points made: I presented some preliminary results at the Climate Engineering Conference in Berlin last August. Basically, everything you´ve mentioned we´ve done at NIOZ in the past two years, including proper lab tests with filtered seawater, and different mixtures of artificial seawater, and controls (of course), where we measured DIC, alkalinity, pH, dissolved silicate and dissolved metals. Also, we´ve fed olivine to common bioturbating coastal macrofauna (lugworms) to see what their potentially enhancing effect might be on olivine dissolution in coastal settings and as we speak/write, students are applying small layers of forsteritic olivine sand in mesocosm setups (1 m2 basins) with natural coastal sediment and running seawater. Results of the shaking experiments and lugworm experiments are nice, and more importantly, consistent and I expect to come out with the first shaking bottle lab experiments in a manuscript in november or december. Depending on the results of the current experiment, the rest wil then follow.
Yes, Papakolea Beach on South Point, Big Island Hawaií is one very nice place where an olivine/basalt mix of grains forms a green beach in a relatively closed embayment. Depending on the wind, the bay is very well accessible, and would serve perfectly as a natural analogue, or at least tell us something on the accumulation of dissolution products on the marine ecosystem. Cheers, Francesc PS I´m away on holiday at the moment, and will only check email irregularly ----- vriendelijke groeten / kind regards, Dr. Francesc Montserrat Netherlands Institute for Sea Research Department of Ecosystem Studies PO Box 140 4400 AC Yerseke The Netherlands Phone: +31 (0)113 577 472 Mobile: +31 (0)6 2481 5595 http://www.nioz.nl/<http://www.nioz.nl> ________________________________ From: [email protected] <[email protected]> on behalf of Parminder Singh <[email protected]> Sent: 01 October 2014 07:59 To: [email protected] Cc: [email protected]; [email protected] Subject: Re: [geo] Natural olivine beaches Hi, Schuilling carried out experiments where modest surf action was imitated by having olivine grains rotate slowly along the bottom of an Erlenmeyer, the water turned an opaque white after a few days of rotation, the pH of the solution had gone up, and many of the slivers had already turned into neoformed grains of brucite, a mineral known to carbonate fast. As for beaches you can find them in Hawaii, Turkey, Galapagos Is. just a few to mention. Regards, Parminder On Wednesday, October 1, 2014 11:19:31 AM UTC+8, Greg Rau wrote: Agree that the silicate mineral sand idea needs testing. I'd first start in the lab with a flask of freshly ground olivine in chemically well characterized, sterile seawater. I would then put this on a shaker table in the dark and let the sand and water gently slosh back and forth for a few days and then measure the SW alkalinity and DIC again. this would give you and idea of the efficacy and kinetics under ideal conditions. Measuring this in a beach setting would be trickier, but possible. My guess is that there are synergies with sediment respiration/microbes that hasten silicate weathering. Add in some fresh sediment to the above flask and see what happens. Greg ________________________________ From: Andrew Lockley <[email protected]> To: geoengineering <[email protected]> Sent: Tuesday, September 30, 2014 11:28 AM Subject: [geo] Natural olivine beaches Hi The proposal for olivine weathering on beaches seems to pass a common sense test. However, there's been a lack of detailed discussion about the occurrence and function of natural olivine beaches, as far as I'm aware. There are a lot of beaches in the world. Olivine is pretty common. How much of a sink is natural beach chemical and mechanical weathering of olivine? It should be easy to find at least one location where there's massive quantities of olivine sand, and take detailed measurements on the carbon sink. I know there's at least one such beach in the literature, but I can't recall discussions of others, nor detailed quantitative research on erosion and sequestration rates at this site Can someone enlighten me as to why this has seemingly been overlooked for detailed study? A -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]<mailto:[email protected]>. To post to this group, send email to [email protected]<mailto:[email protected]>. Visit this group at http://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/geoengineering. For more options, visit https://groups.google.com/d/optout.
