| Summary: | Miki i skład ziarnowy współczesnych mułów we fiordach Spitsbergenu: studium osiadania zawiesiny XRD, IR and chemical determinations of bulk mineral composition and clay mineralogy have been carried out along with textural analysis in glacial-marine muds of Homsund and Wijdefjorden on Spitsbergen. Distribution of micas and texture of silt and clay fractions of bottom sediment were found to be sensitive indicators of environmental conditions of supply, dispersal and settling of suspension in the fjord. Quantitative analysis of two dioctahedral mica poly types (2M1 and 1Md) distinguishes clay-mineral provinces within bottom muds, reveals mineral segregation of clay suspension during transport, and allows one to name differences in suspension settling process among various zones of the tidewater-glacier basins. These zones are: (1) still-water, occasionally turbulent zone in contact with ice-cliiT, (2) meltwater jet zone, (3) proximal zone beyond meltwater jet, (4) slow surface-advection zone, (5) bottom-current dominated distal zone, and (6) still-water ice-rafting dominated distal zone. The results point to geologically important phenomena in the tidewater-glacier sedimentary system: (1) lithology of source substratum rocks on land is inherited by bottom sediment of the fjord, (2) selective settling of clays results in preferential deposition of muscovite in ice-proximal settings, the process being well expressed by a lateral change of 2M1-muscovite to 1Md-illite ratios, (3) flocculation strongly coerced by turbulence occurs along shear surface beneath meltwater jet; single grains and immature floes are captured here within underlying still-water layer producing in the ice-proximal zone mineral sorting and exceptionally high accumulation rates of fine sediment, (4) flocculation of clays mainly due to differences in single-grain velocities takes place in the show-advection surface water layer; this process controls settling of suspension in the distal, slow-advection zone producing relatively low accumulation ...
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