Page 51: of Marine Technology Magazine (May 2012)

Hydrographic Survey

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www.seadiscovery.com Marine Technology Reporter 51bags.The dissolution plates are basically plane pills, manufac- tured with original chalk taken from the system and fixed on a surface that has been placed in several locations of the underwater system. Knowing the initial volume and weight of these plates, it is possible to calculate the volume and mass loss after a certain period of time. The dissolution bags are samples that have been meas- ured and weighted, placed in permeable bags. With this procedure, each side of the sample is in contact with water, giving an idea of the velocity of dissolution, although it is a little bit distorted and accelerated. In order to establish a base line, during the first incursion in the cave system, water samples have been taken in order to obtain values of PH, temperature, conductivity, turbid- ity, minerals and dissolved oxygen. Due to the extreme conditions, which are responsible for a human and economic weakening during each incursion to the cave system, initially only once every 6 months these dives will be carried out, following the marked hydric and climatic seasonality, evidenced at the beginning of the austral spring and autumn.In the future, part of these investigations will be carried out by ROVs specially adapted for these purposes. Vehicles of the FO II type from Mariscope will be adapted with special camera and lighting systems, oceanographic sensorsand other instruments, in order to be able to carry out the measurements without putting at risk the divers. MTR#4 (50-64):MTR Layouts 5/4/2012 3:19 PM Page 51

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