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Overview
CHAPTER I.--ON THE ELEVATION OF THE EASTERN COAST OF SOUTH AMERICA.
Upraised shells of La Plata.--Bahia Blanca, Sand-dunes and Pumice-pebbles.-
-Step-formed plains of Patagonia, with upraised shells.--Terrace-bounded
valley of Santa Cruz, formerly a sea-strait.--Upraised shells of Tierra del
Fuego.--Length and breadth of the elevated area.--Equability of the
movements, as shown by the similar heights of the plains.--Slowness of the
elevatory process.--Mode of formation of the step-formed plains.--Summary.-
-Great shingle formation of Patagonia; its extent, origin, and
distribution.--Formation of sea-cliffs.
CHAPTER II.--ON THE ELEVATION OF THE WESTERN COAST OF SOUTH AMERICA.
Chonos Archipelago.--Chiloe, recent and gradual elevation of, traditions of
the inhabitants on this subject.--Concepcion, earthquake and elevation of.-
-VALPARAISO, great elevation of, upraised shells, earth or marine origin,
gradual rise of the land within the historical period.--COQUIMBO, elevation
of, in recent times; terraces of marine origin, their inclination, their
escarpments not horizontal.--Guasco, gravel terraces of.--Copiapo.--PERU.--
Upraised shells of Cobija, Iquique, and Arica.--Lima, shell-beds and sea-
beach on San Lorenzo.--Human remains, fossil earthenware, earthquake
debacle, recent subsidence.--On the decay of upraised shells.--General
summary.
CHAPTER III.--ON THE PLAINS AND VALLEYS OF CHILE:--SALIFEROUS SUPERFICIAL
DEPOSITS.
Basin-like plains of Chile; their drainage, their marine origin.--Marks of
sea-action on the eastern flanks of the Cordillera.--Sloping terrace-like
fringes of stratified shingle within the valleys of the Cordillera; their
marine origin.--Boulders in the valley of Cachapual.--Horizontal elevation
of the Cordillera.--Formation of valleys.--Boulders moved by earthquake-
waves.--Saline superficial deposits.--Bed of nitrate of soda at Iquique.--
Saline incrustations.--Salt-lakes of La Plata and Patagonia; purity of the
salt; its origin.
CHAPTER IV.--ON THE FORMATIONS OF THE PAMPAS.
Mineralogical constitution.--Microscopical structure.--Buenos Ayres, shells
embedded in tosca-rock.--Buenos Ayres to the Colorado.--S. Ventana.--Bahia
Blanca; M. Hermoso, bones and infusoria of; P. Alta, shells, bones, and
infusoria of; co-existence of the recent shells and extinct mammifers.--
Buenos Ayres to St. Fe.--Skeletons of Mastodon.--Infusoria.--Inferior
marine tertiary strata, their age.--Horse's tooth. BANDA ORIENTAL.--
Superficial Pampean formation.--Inferior tertiary strata, variation of,
connected with volcanic action; Macrauchenia Patachonica at S. Julian in
Patagonia, age of, subsequent to living mollusca and to the erratic block
period. SUMMARY.--Area of Pampean formation.--Theories of origin.--Source
of sediment.--Estuary origin.--Contemporaneous with existing mollusca.--
Relations to underlying tertiary strata. Ancient deposit of estuary
origin.--Elevation and successive deposition of the Pampean formation.--
Number and state of the remains of mammifers; their habitation, food,
extinction, and range.--Conclusion.--Supplement on the thickness of the
Pampean formation.--Localities in Pampas at which mammiferous remains have
been found.
CHAPTER V.--ON THE OLDER TERTIARY FORMATIONS OF PATAGONIA AND CHILE.
Rio Negro.--S. Josef.--Port Desire, white pumiceous mudstone with
infusoria.--Port S. Julian.--Santa Cruz, basaltic lava of.--P. Gallegos.--
Eastern Tierra del Fuego; leaves of extinct beech-trees.--Summary on the
Patagonian tertiary formations.--Tertiary formations of the Western Coast.-
-Chonos and Chiloe groups, volcanic rocks of.--Concepcion.--Navidad.--
Coquimbo.--Summary.--Age of the tertiary formations.--Lines of elevation.--
Silicified wood.--Comparative ranges of the extinct and living mollusca on
the West Coast of S. America.--Climate of the tertiary period.--On the
causes of the absence of recent conchiferous deposits on the coasts of
South America.--On the contemporaneous deposition and preservation of
sedimentary formations.
CHAPTER VI.--PLUTONIC AND METAMORPHIC ROCKS:--CLEAVAGE AND FOLIATION.
Brazil, Bahia, gneiss with disjointed metamorphosed dikes.--Strike of
foliation.--Rio de Janeiro, gneiss-granite, embedded fragment in,
decomposition of.--La Plata, metamorphic and old volcanic rocks of.--S.
Ventana.--Claystone porphyry formation of Patagonia; singular metamorphic
rocks; pseudo-dikes.--Falkland Islands, palaeozoic fossils of.--Tierra del
Fuego, clay-slate formation, cretaceous fossils of; cleavage and foliation;
form of land.--Chonos Archipelago, mica-schists, foliation disturbed by
granitic axis; dikes.--Chiloe.--Concepcion, dikes, successive formation
of.--Central and Northern Chile.--Concluding remarks on cleavage and
foliation.--Their close analogy and similar origin.--Stratification of
metamorphic schists.--Foliation of intrusive rocks.--Relation of cleavage
and foliation to the lines of tension during metamorphosis.
CHAPTER VII.--CENTRAL CHILE:--STRUCTURE OF THE CORDILLERA.
Central Chile.--Basal formations of the Cordillera.--Origin of the
porphyritic clay-stone conglomerate.--Andesite.--Volcanic rocks.--Section
of the Cordillera by the Peuquenes or Portillo Pass.--Great gypseous
formation.--Peuquenes line; thickness of strata, fossils of.--Portillo
line.--Conglomerate, orthitic granite, mica-schist, volcanic rocks of.--
Concluding remarks on the denudation and elevation of the Portillo line.--
Section by the Cumbre, or Uspallata Pass.--Porphyries.--Gypseous strata.--
Section near the Puente del Inca; fossils of.--Great subsidence.--Intrusive
porphyries.--Plain of Uspallata.--Section of the Uspallata chain.--
Structure and nature of the strata.--Silicified vertical trees.--Great
subsidence.--Granitic rocks of axis.--Concluding remarks on the Uspallata
range; origin subsequent to that of the main Cordillera; two periods of
subsidence; comparison with the Portillo chain.
CHAPTER VIII.--NORTHERN CHILE.--CONCLUSION.
Section from Illapel to Combarbala; gypseous formation with silicified
wood.--Panuncillo.--Coquimbo; mines of Arqueros; section up valley;
fossils.--Guasco, fossils of.--Copiapo, section up valley; Las Amolanas,
silicified wood.--Conglomerates, nature of former land, fossils, thickness
of strata, great subsidence.--Valley of Despoblado, fossils, tufaceous
deposit, complicated dislocations of.--Relations between ancient orifices
of eruption and subsequent axes of injection.--Iquique, Peru, fossils of,
salt-deposits.--Metalliferous veins.--Summary on the porphyritic
conglomerate and gypseous formations.--Great subsidence with partial
elevations during the cretaceo-oolitic period.--On the elevation and
structure of the Cordillera.--Recapitulation on the tertiary series.--
Relation between movements of subsidence and volcanic action.--Pampean
formation.--Recent elevatory movements.--Long-continued volcanic action in
the Cordillera.--Conclusion.
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