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Show 178 OLDER PLIOCENE PERIOD. [Cl1. Xlll. No. 37. No. 38. Bent strata of loam in tlte cliffs between Cromer and Runton. Folding of the strata between East ana West Runton. In the last of these cuts a central n~cleus of sand is surrounded by argillaceous and sandy layers. This phenomenon is very frequent, and there are instances where the materials thus enveloped consist of broken flints mingled with pieces of chalk, forming a white mass encircled by dark_ laminated clay. The 'diameter of these included masses, as seen in sections laid open in the sea-cliffs, varies from five to fifteen feet. East of Sherringham, a heap of partially-rounded flints, about five feet in diameter, is nearly enveloped by finely-laminated strata of sand and loam, and some of the loam is entangled in the midst of the flints. Section in the Cliffs east of Sherringham. a, Sand and loam in thin layers. No.39. In this and similar instances, we may imagine the yielding strata, a, to have subsided into a cavity, and the flints belonging to a superincumbent bed to have pressed down with their weight, so as to cause the strata to fold round them. That some masses of stratified sand and loam have actually sunk down into cavities, or have fallen like land slips into ravines, seems indicated by other appearances. Thus, near Sherringham, the argillaceous beds, a, represented in the annexed diagram (No. 40), are cut off abruptly, and succeeded by the vertical and contorted series, b, c. '!'he face of the cliff here Ch. XIII.] CRAG OF NORFOLl\. 179 represented, is 24 feet in height · Some of tl 1e 1a yers m. b b are composed of pebbles, and these alternate with thin b~d~ = 1 Section east of Sltel'l'ingham, Norfolk. a, Sand, loam, nnd blue clay. b, b, Sand and gravel. c, Twisted beds of loam, ofloose sand. The whole set must once have been horizontal and must have moved in a mass, or the relative position of the several parts would not have been preserved. Similar app~arances may, perhaps, be produced when chasms open durmg earthquakes and portions of yielding strata fall in from above and are engulphed. Prot.r uded m.a sses .o f chalk ·- But whatever opm..10 n we may entertam on this pomt, we cannot~~. doubt tl1 a t su b terranean No.4l. 0 1\' ,, . ·jl' c';alli . a' 11 ill'\' . . f' '' · Sea Stdc vtew of a pro mon t ory oi f chalk and crag, Trimming/tam-,· N orf-olk. a, Gravel and ferruginous sand rounded and . ~orne quartz pt>bblcs, 3 f~et. angular pH!ces of chalk flint, with b, Lammated blue clay 8 fl:!et d, Dark blue clay with frng . t f . c, Yt>llow sand, 1 foot 6 inches. e Yell I men s o marme shells 6 feet ' ow oam and flint gravel 3 feet ' . • g, Sand anilluam, 12 feet. ' • f, Light Llue clay, 1 foot. h, Yellow and whl't e sanu.1l 1o aml ancl gravel, nbout 100 feet. N2 |