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Show 130 [Ch.X. NEWER PLIOCENE PERIOD· . 8. .1 Calabria and the Morea, structure of the interior, as m ICI y, . 1 ' On the other b nean movements are now VlO ent. where su terra . ··k· fact that there is no example liand, it is a still more stn mg ' . . d b . ·"t" district now habitually agltate y of any extensive man tme ' . . d 1 . h l s not when carefully mvest1gate , great earthquakes, w uc 1 a : f h Recent or newer yielded traces of marine strata, elth~r o t e Pliocene eras, at considerable elevatwns. . Chili.-Conception Bay.-In illustratwn of the above re. t. that on the western coast of South marks we may men wn, . . Amen.c a marm. e d eposi' ts occu,. r ' contaimng pre.c.is ely the same 1. · cr in the Pacific. In Chili, for example, shells as are now 1vmo . . . 1! t d * micaceous sand contammg the foss1l re-as we be1ore sta e ' ' . mam· s f h I'es as now inhabit the Bay of Conception, 0 sue spec 1! d t tl } are 1oun a 1e 1e 1•o O 'ht of from 1000 to 1500 feet above th.e Ie ve1 of tl1 e oce an . It is impossible to say how. much of th1s n·s e may h ave t a }{en place during the Recent penod. We have en d eavoure d t o Sho\.,,, that one earthquake raised this part of h Cl ·1· t 1 " 0 t e 11 tan coas , 1750, to the height of at le.a st 25 fe.e t a b ove I· ts 11! ormer• level · If we could suppose a contmued ser1es of such shocks, one in every century, only 6000 years would be required to uplift the coast 1500 feet. But we have no d ata 11! 0r m• 11! err•m g tl1at so great a quantity of elevation has taken place in that space of time, and although we cannot assu~e that the micaceous sand may not belong to the Recent period, we think it more probable that it was deposited during the newer Pliocene period. . Peru.-We are informed by Mr. A. Cruckshanks, that m l 11 f Lima or Rimao where the subterranean move· t 1e va ey o ' ' . . . ments have been so violent in recent times, there are mdtcatl~ns not only of a considerable rise of the land, bu~ ~f th~t me h vinO" resulted from successive movements. Distmct hnes of a~ciet~t sea-cliffs have been observed at various heights, at the base of which the hard rocks of greenstone are hollowed ~ut into precisely those forms which they now assume between. high d low water mark on the shores of the Pacific. Immediately an . · b h t wed with below these water-worn hnes are anCient eac es s re "' Vol. i. chap. xxv, Ch.X.] PARALLEL ROADS OF COQUIMBO, 131 rounded blocks. One of these cliffs appears in the hill behind Banos del Pujio, about 700 feet above the level of the sea, and 200 above the contiguous valley. Another occurs at Aman ... caes, at the height of perhaps 200 feet above the sea, and others at inte1·mediate elevations. Parallel roads of Coquimbo.-We can hardly doubt that the parallel roads of Coquimbo, in Chili, described by Captain Hall, owe their origin to similar causes. These roads, or shelves, occur in a valley six or seven miles wide, which descends from the Andes to the Pacific. Their general width is from 20 to 50 yards, but they are, at some places, half a mile broad. They are so disposed as to present exact counterparts of one another, at the same level, on opposite sides of the valley. '!'here are three distinctly characterized sets, and a lower one which is indistinct when approached, but when viewed from a distance is evidently of the same character with the others. Each resembles a shingle beach, being formed entirely of loose materials, principally water-worn, rounded stones, from the size of a nut to that of a man's head. The stones are principally granite and gneiss, with masses of schistus, whinstone, and quartz mixed indiscriminately, and all bearing marks of having been worn by attrition under water*. The theory proposed by Captain Hall to explain these appearances is the same as that which had been adopted to account for the analogous parallel roads of Glen Roy in Scotland t. The valley is supposed to have been a lake, the waters of which stood, originally, at the level of the highest road, until a flat beach wns produced. A portion of the barrier was then broken down, which allowed the lake to discharge part of its waters into the sea, and, consequently, to fall to the second level; and so on successively till the whole embankment was washed away, and the vall~y left as we now see it. As I did not feel satisfied with this explanation, I applied to * Captain Hall's South Amel'ica, vol. ii. p. 9. t s~e Sir T. D. Lall(l~r, :Eel. Roy. Soc, Trans., vol. ix., aud Dr. Macculloch, Geol. Trans., 1st Serie_s1 vol. iv, P• 314, K2 |