Laminated clay

Slackwater facies are found in most cave deposits, usually as the final layer to be deposited. The slackwater facies appears at the top of the section in Figure 4 as the laminated clay overlying the channel deposits. Even when passages are nearly plugged... 

The black layer is a 3.5 cm thick, black to very dark gray clayey silt with weak lamination. The most notable feature of this layer is the abundance of euhedral, starburst shaped Mn oxide minerals that average 0.5 to 0.1 mm in diameter (Figs. 4E and 4F). The detrital component of this unit is dominated by quartz silt. The upper contact of this unit is slightly eroded and marked by clay clasts and a transition to red laminated clay. 

The red layer is a 1 cm thick zone of red laminated clays and numerous clay clasts. In this interval are at least five sets of clay clasts overlain by clay laminae and capped by an iron-rich coating. The red clay laminae drape over individual clasts and are also deformed beneath clasts (Fig. 4G). Certain clast layers are predominantly composed of massive silty gray clay. Clasts are relatively large and elongated (up to 3 mm long x 1 mm wide) compared to other units. The upper contact with the upper orange layer is sharp and planar. 

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

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

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

Bell, F.G. and Coulthard, J.M. 1997. A survey of some geotechnical properties of the Tees Laminated Clay of central Middlesbrough, north east England. Engineering Geology, 48, 117-133. 

Laminated clay is of detrial origin, i.e., formed outside the sandstone... 

Adhesives for paper tubes, paperboard, cormgated paperboard, and laminated fiber board are made from dispersions of clays suspended with fully hydrolyzed poly(vinyl alcohol). Addition of boric acid improves wet tack and reduces penetration into porous surfaces (312,313). The tackified grades have higher solution viscosity than unmodified PVA and must be maintained at pH 4.6—4.9 for optimum wet adhesion. 

Test borings revealed that the fill material consists predominantly of thinly laminated silt with a relatively high clay content. Occasional discontinuous layers of fine sand were encountered at random locations, both horizontally and vertically. The water table gradient under nonpumping conditions was toward the canal with an approximate gradient of 0.011 ft/ft. Slug tests indicated an effective permeability of 1 x 10-5 cm/s. 

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],... 

Ross and Hendricks (1945) Ancon, Canal Zone, laminated organic clay. 

The manufactured 90 mm x 90 mm x 10 mm three-layered B4C/B4C-30wt%SiC tiles were tested as armor [67], The photographs of the experiment set-up of the ballistic test as well as a residual impression in the clay box that was used as one of the criteria in the ballistic performance of laminates are shown in Fig. 7.17. The ballistic penetration tests were performed to evaluate the ballistic performance of the laminates. Depth of penetration tests were used to evaluate the ballistic performance of the composite laminates. In addition, pure B4C monolithic ceramics were used as a standard for the test. Test panels were made using the three-layered B4C/B4C-SiC laminate and B4C monolithic ceramic material as the hard face. While the B4C monolithic tile had 100% of its theoretical density, the three-layered B4C/B4C-30wt%SiC laminates had about 3-4% of porosity. A commonly used Spectra fiber-reinforced polymer composite was used as backing plates. The targets were mounted on clay and the projectile was shot at the target at a specific velocity. 

The design of the test panels was selected to ensure defeat of the threat. The depth of penetration of the projectile into the backing was measured by peeling of the unpenetrated layers of the backing plate, and the diameter of the impression on the clay after the projectile had been shot was used to evaluate the ballistic performance of the laminate composites. The results of the ballistic performance evaluation are shown in Fig. 7.18. As one can see there was no significant difference in penetration of the projectile into pure B4C monolith ceramics and three-layered composite. 

Interpolation or intercalation (see Intercalation Chemistry) is said to occur when additional species are placed into a host stmcture to change either composition or properties. At one extreme, intercalation can refer to the insertion of gnest molecnles into cage stmctures such as that of the zeolites (see Zeolites), or between the layers of laminated compounds snch as the clays (see Silicon Inorganic Chemistry). At the other extreme, the insertion of small atoms snch as C or N into metal phases to form interstitial alloys (see Alloys Carbides Transition Metal Solid-state Chemistry Nitrides Transition Metal Solid-state Chemistry), is inclnded in the category. A large variety of stmctures can be found in snch materials, and... 

Suggested Uses Textile Adhesive/Laminating Acrylic copolymer emulsion. Excellent pigment and clay binding properties. 

The gravels, sands and clays in Reed Chamber in the lowermost epiphreatic level undoubtedly represent fluvial sediments deposited by the stream flowing through the cave at the time, as the sands occasionally show ripple cross-lamination. 

Most caves in the Edwards Limestone do contain a clay suite very similar to the clays found in the suspended sediment discharged from Barton Springs. The I/S in the cave clays is identical to the BS I/S (Fig. 5). The presence of laminations in some cave clay deposits indicates that, like the terra rossa, the clastic material was washed into caves and was not derived from dissolution of the Edwards Limestone (Kastning, 1986 Ellis, 1986 Flavorka et ak, 1996). Similarity of clay suites in the caves and in the discharged sediment implies that the source area for the clays, and the processes leading to its deposition in caves or transport through the aquifer, have been the same for an extended period of time. 

The Cleveland Member consists primarily of black to brownish-black laminated siliceous shale. It contains minor amounts of calcareous laminae and cone-in-cone limestone. Pyrite is present as nodules, framboids, and irregular forms. Other primary minerals include illite clay and clay- and silt-size quartz. 

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