Problems of pressure estimation in high temperature experiments using solid media apparatus with particular reference to piston-cylinder and anvil-with-hole apparatus (Part I)

The high albite (Ab)⇄jadeite (Jd)+quartz(Q) reaction (1) and the quartz(Q)⇄coesite (Cs) transformation (2) have been determined within the temperature range of 1000–1100°C and 1000–1400°C respectively under variable pressures using an anvil-with-hole apparatus. The equilibrium curves for the two reactions as a function ofP andT are as follows: P=−1·33+0·0296T (reaction 1);P=18·949+0·0111T(reaction 2). These two lines intersect at 31·1±0·5kb and 1096°C. The possibility of using an anvil-with-hole apparatus for conducting current investigations is discussed in this paper.