380 J. BAERELL FLUVIATILE ORIGIN OF OLD RED SANDSTONE 



the left bank. A hundred yards further up, similar remains occur in a band 

 of red sandstone at the bottom of the low cliff. 



"The sandstones become more massive and false-bedded as they ascend in 

 the series, till at a point in the stream a little more than a mile southeast 

 from Easter Gospetry they are succeeded by the thick zone of soft white and 

 yellow sandstones already mentioned. These differ considerably from the 

 strata below them, not merely in color, but in texture, composition, and struc- 

 ture. They are, as a whole, coarse in their material, which consists of well- 

 rounded grains of quartz, not infrequently blue, and of rolled grains of felspar. 

 The coarser layers show well the composition of the sediment, which must 

 have been derived from the decay of rocks wherein water-clear and also blue 

 hyaline quartz, as well as white and pink felspar, abounded. So felspathic 

 and decayed are some bands of these sandstones that, when a handful of their 

 substance is thrown into water, a white cloud of clay particles immediately 

 appears. A distinctive feature of this group of strata is to be found in their 

 remarkable false bedding. One bed may be seen with its current lamination 

 inclined towards northwest at 35°. This lamination terminates upward along 

 a sharply-defined plain forming the bottom of another bed in which the layers 

 dip southward at 3°. These, again, are truncated in the same sharp way by 

 another bed in which the layers dip northward at 5°, while above it lies a 

 band in which the lamina? are inclined in the same direction at 15°. These 

 structures furnish a suggestive picture of the shifting water-currents by which 

 this group of pale sandstones was accumulated. 



"These white and yellow sandstones appear to form the uppermost zone of 

 the 'Dura Den beds' of the east of Fife. Though they have not yielded here 

 the same remarkable assemblage of fishes as that for which Dura Den itself 

 has long been celebrated, they contain fish-remains, as was recently ascer- 

 tained by Mr. B. N. Peach. They perhaps only need to be quarried and laid 

 open in a fresh and unweathered condition to supply a similar series of 

 ichthyolites." 35 



These descriptions suggest in the conglomerates, breccias, and false- 

 bedded sandstones with fish fragments a greater degree of torrential river 

 action than was characteristic of most of the Lower Old Eed. Hickling 

 calls attention also to the prevalence of the cornstone type of deposit. 

 The soft white and yellow sandstones with well rounded grains of quartz 

 and remarkable false-bedding suggest the agency of wind as an agent of 

 accumulation. There is nothing in the descriptions, however, which indi- 

 cates that fluviatile transportation may not have been dominant. It is 

 true, Goodchild states that the sandstones are often full of desert-sand 

 grains and are highly false-bedded in places, like an old desert sand- 

 dune. 36 But little judicial weight can be attached to this statement, how- 

 ever, since Goodchild nowhere recognized the possible importance of 

 fluviatile aggradation in humid or semi-arid climates as distinct from 

 true desert conditions. There is nothing to indicate in G-oodchild's work 

 but that all red, fossil-barren, and false-bedded sandstones are of desert 



35 Geology of central and western Fife and Kinross-shire. Mem. Geol. Survey Scot- 

 land. 1900. pp. 34, 35. 



58 The older Deutozoic rocks of North Britain, Geo!. Mag., Dec. 6, vol. i, 1904, p. 592. 



