The Andes of southern Peru, geographical reconnaissance along the seventy-third meridian . 2 °0 O -L3 t-i C3 hypoof Cawo diortion 2 -^ ft r£ rH ^ +3 CD 01 rt presentsd characteft of tinly a smal u o CS o ^ CD ^ 02 -P s * £ +3 lH m rt 2 cS o> (0 cS -r* « cS S i3 C rd M IB 3 . 0) cS H O -P .rt rrj -+5 Td d Vi rj CD rrt ?Si «> o £; oj CD ft IE rt « 02 r3 ^ -, CDP ft J> ^ CD 02 CD r—1 rt cj H ro r>> ft ^ -2 cS H s J rQ d rcj S o f! -p CD 02 CD cj «fH CD d CD .s py-s a PHYSIOGRAPHIC AND GEOLOGIC DEVELOPMENT 247 the region now occupied by the Andes. However, from the rela-tion of the
The Andes of southern Peru, geographical reconnaissance along the seventy-third meridian . 2 °0 O -L3 t-i C3 hypoof Cawo diortion 2 -^ ft r£ rH ^ +3 CD 01 rt presentsd characteft of tinly a smal u o CS o ^ CD ^ 02 -P s * £ +3 lH m rt 2 cS o> (0 cS -r* « cS S i3 C rd M IB 3 . 0) cS H O -P .rt rrj -+5 Td d Vi rj CD rrt ?Si «> o £; oj CD ft IE rt « 02 r3 ^ -, CDP ft J> ^ CD 02 CD r—1 rt cj H ro r>> ft ^ -2 cS H s J rQ d rcj S o f! -p CD 02 CD cj «fH CD d CD .s py-s a PHYSIOGRAPHIC AND GEOLOGIC DEVELOPMENT 247 the region now occupied by the Andes. However, from the rela-tion of the Carboniferous to the basal schists, and the most con-servative extension of the known Carboniferous, it may be in-ferred that the Carboniferous sea did not completely cover theentire area but was broken here and there by island masses in theform of an elongated archipelago. The presence of land plantsin the Carboniferous of Pisco warrants the conclusion that a sec-ond island mass, possibly an island chain parallel to the first, ex-tended along and west of the present [X-:-] Alluvium i%^ III IHSandstone s Shale | I Volcanic CRETACEOUS The Cretaceous formations are of very limited extent in thebelt of country under consideration, in spite of their generallywide distribution in Peru. Theyare exposed distinctly only onthe western border of the Cor-dillera and in special the gorge of Cotahuasi, overseven thousand feet deep, abouttwo thousand feet of Cretaceouslimestones are exposed. Theseries includes only a very re-sistant blue limestone and ter-minates abruptly along a well-marked and highly irregularerosion surface covered by al-most a mile of volcanic ma-terial, chiefly lava flows. Thecharacter of the bottom of thesection is likewise unknown,since it lies apparently far be-low the present level of ero-sion. The Cretaceous limestones of the Cotahuasi Canyon are every-where greatly and irregularly disturbed. Typical conditions arerepresent
Size: 1838px × 1360px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorbo, bookcentury1900, bookdecade1910, booksubjectgeology
