Clay mineral composition of sediments from Songkhla lagoon, southern Thailand
2001
Somsak Maneepong(Walailak Univ., Nakhon Si Thammarat (Thailand). Inst. of Agricultural Technology) E-mail:[email protected]
Clay minerals play an important role in nutrients as well as toxic elements absorption, which affect the ecology of biota. Moreover, they may be used to identify sources of sediment. Six sediment samples from Thale Noi and Thale Luang, and 5 soil samples from one soil profile, were examined by X-ray diffraction. The mineralogy of the clay-fraction sediments from Thalae Noi and Thale Luang were similar. Kaolins dominated in all samples, with substantial amounts of smectite and micas. Quartz was also found in negligible amounts. There was no evidence of feldspar, gibbsite and halloysite, which was found in stream sediments previously. The amount of smectite varied substantially between sampling sites. Sediments taken near the mouth of Ranot Stream contained the largest amount of smectite. The high smectite content may be due to enrichment, and smectite content at its source. The mineralogy of clay-fraction soils taken from a profile on the east coast of the lagoon was similar to that of the lagoon sediments. Kaolins were found to be the dominant mineral in every horizon. The smectite content increased with depth.
显示更多 [+] 显示较少 [-]