330 



MR. &. BAEHOW ON THE OCCURRENCE OE [Aug. I9OI, 







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Survey memoir on that district. 

 Beyond the bend for 250 yards, 

 the river flows over Green Rock 

 with numerous small vertical in- 

 folds of jasper. 



The dominant member of the 

 series displayed in the second or 

 central part of the i!^orth Esk 

 section is a more or less crushed 

 basic igneous rock, to which the 

 name Green Rock has been 

 applied, owing to the persistent 

 green colour produced by de- 

 formation. Jasper and jaspery 

 phyllite are so constantly asso- 

 ciated with these igneous rocks that 

 the name Jasper and Green- 

 Rock Series seems appropriate. 

 It may here be noted that neither 

 in the North Esk section, nor at 

 any other locality in that region, 

 is the base of this series visible ; 

 indeed, there can be little doubt 

 that denudation has exposed only 

 the top of what may possibly be 

 a complicated series of igneous 

 rocks. 



The third part of the section in 

 the North Esk begins at a point 

 about 250 yards above the sharp 

 bend already mentioned. Imme- 

 diately to the north of the Green 

 Rock is a coarse green conglo- 

 merate, made np of the under- 

 lying igneous materials, together 

 with numerous small fragments 

 of red jasper. The conglomerate 

 is traversed by small planes of 

 movement, and a more persistent 

 movement-plane occurs at its base, 

 where calcareous material has ac- 

 cumulated. The upward succes- 

 sion can be studied only when 

 the river is low. Next in order 

 comes a green grit, which heralds 

 the beginning of the Margie 

 Grits. As we ascend in the series 

 the pebbles in these grits be- 

 come smaller and the proportion 

 of cementing - material becomes 



