Techniques for Removing Interstitial Water From Coarsegrained Sediments for Chemical Analyses

Three methods, (a)dessication, (b)gas extraction and (c)immiscible‐liquid extraction, are described and evaluated for removing interstitial water from coarse‐grained sedi‐ ments for semi‐quantitative and quantitative chemical analyses. The dessication method is useful for chlorinity or chlorosity determinations and (with a correction of 5%) gives results probably accurate to within about ± 2O% Extraction of interstitial water with gas of high relative humidity gives results which are correct to within an error of ± l.O% The chlorosity of interstitial water extracted by forcing a high‐ viscosity epoxy plasticizer (immiscible with water) through the sediment falls within about ± 0.1% of the correct value. The immiscible‐extraction method is therefore recommended for work requiring quantitative knowledge of interstitial water chemistry.