"NSLSD"@en . . "stable"@en . "Non-clastic siliceous sediment"@en . "Non-clastic siliceous sediment"@en . . . . "Non-clastic siliceous sediment - In the Rock Classification Scheme, these are sediments which are composed of more than 50% silica of biogenic or chemical origin. This is the unlithified equivalent of siliceous rock. British Geological Survey Research Report RR/99/03, section 8.1 and fig. 12."@en .