The structural geology of boulby (potash) mine, Cleveland, United Kingdom

Potash Deposits

“…Smith (1973), however, interpreted the same data differently and postulated that these minerals crystallized under sebkha conditions. When later large scale observations could be made from mining operations Talbot et al (1982) found one layer of the Boulby halite with octahedral patterns that resemble a dry lake surface, but being shallow once does not necessarily imply that the brine depth was always shallow. For the insolubles they found rather conclusive evidence that the clay and anhydrite actually had little relationship to the depth of the evaporating basin, but were a relic of post-depositional changes.…”

“…Its upper boundary with a grey anhydrite shale, however, though fairly smooth and distinct, is highly irregular, giving the deposit a general rolling, mUltiple pillow shape (Figure 2-12). Talbot et al (1982) suggest that brine may have permeated the potash deposit (probably the Ca-Mg dolomitization brine that now still oozes from cuts in the Boulby Halite), and that at its period of deepest burial (2,200 Figure 2-11. An example of a fault plane and its effect upon the Boulby potash area strata (Talbot et al 1982).…”

“…Talbot et al (1982) suggest that brine may have permeated the potash deposit (probably the Ca-Mg dolomitization brine that now still oozes from cuts in the Boulby Halite), and that at its period of deepest burial (2,200 Figure 2-11. An example of a fault plane and its effect upon the Boulby potash area strata (Talbot et al 1982). Reprinted by permission of Tectonophysics.…”

“…Talbot et al (1982) have proposed that the sylvinite reached it's present position by flowing into the grey anhydrite shale and salt clay (also called a "carnallite marl", but at Boulby it contains neither carnallite nor carbonates, and consists of clay, halite and anhydrite) that lies on top of it. The most unique feature of the deposit is that the sylvinite "resembles a metamorphic gneiss, both in terms of crystal fabric and the fact that it contains many rounded fragments of rocks from adjacent beds" (Woods 1979).…”

Hydrogen from Radiolysis of Aqueous Fluid Inclusions during Diagenesis

“…2, nearby at Aislaby [12] (Figure 2). The mine exploits marine evaporites of Upper Permian age (Zechstein) including thick beds of the potassium chloride sylvite [13,14]. The sylvite and halite from the Boulby mine were collected underground from stock piles accumulated from thick (>1 m) beds of relatively pure salt, rather than intergrowths of the two minerals.…”