Varved clay

At the White Lake Cu-Zn sulfide deposit (near Flin Flon, Manitoba) no geochemical signature had been obtained from conventional soil geochemistry. Where the deposit is overlain by 23m of barren rock and 8m of glacial overburden including an upper 1m of impermeable varved clay, a strong characteristic rabbit-ear H anomaly clearly indicates the location of the orebody, as predicted by the electrochemical model (Govett 1976). 

Fortunately the Hudson Bay lowland-derived varved clay is alkaline and Ca-rich and provided an ideal substrate in which... 

Fig. 1. Profile from the top of varved clay over a VMS deposit in Northern Quebec showing the relationship between H concentration and aqua regia soluble Ca. (adapted from Smee 1983).

DeGroot, D. J. Lutenegger, A. J. 1994. A comparison between field and lab measurements of hydraulic conductivity in a varved clay. Hydraulic Conductivity Waste Contaminant Transport in Soil (STP 1142), ASTM, West Conshohocken/PA, 300-317. 

Varved clays, Elk Valley, British Columbia Laminated clays, Teesside, England ... 

Varved Clay. A clay deposited in layers, some coarse, others fine and silty. 

Varve or rhythmites chronology is another approach based on the examination of geological materials. In this model, the distribution of the laminated sediments formed in the bottom of the beds of dried-out lakes (as a consequence of the seasonal melting of glaciers and the subsequent deposition of coarse particles supplied by streams, followed by finer materials such as sand, silt, and clay) is analyzed and correlated with climate changes [64],... 

Andren, T.A., and Sohlenius, G. (1995) Late Quaternary development of the north-western Baltic proper—results from the clay-varve investigation. Quart. Inti. 27, 5-10. 

Mammoth Cave provides excellent exposures of slackwater facies (Fig. 4). At the tops of most sediment piles is a layer, seldom more than a few cm thick, of thinly layer clay and very fine silt. Some of these sedimentary layers are varved, apparently representing an annual cycle of flooding with the rise and fall of the ancestral Green... 

Field vane test Clay Undrained shear strength Test shonld be used with care, particularly in fissured, varved and highly plastic clays ASTM D 2553-72 Bjerrum (1972) Schmertmann (1975) Wroth and Hughes (1973) Wroth (1975) BS 5930 (1999)-Cl 25.3... 

Medium Varved and laminated clays Firm to stiff clays... 

Table 5.19. Some properties of varved and laminated clays...

---