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Feb. 1^st [1835] — Chiloe. —

Pebbles in Chevereas creek are contained in the true tertiary formation. — At the head there is an East dip: which probably belongs to the troubled band. — I see there is yellow carb. of lime crystallized in the fissures. — Sphaerical hard concretions follow on each side lines of fissure. —

Proceeding along the straight coast South of Huapi Lacuy. (We first find some pebbles imbedded lying unconformably on common strata) there is a West dip, it is the line of strike of the Huepacho shoal. — Then we have some little horizontal. Then the dip appears to diverge from a curve [sketch] NE E
Ne being the more common one: & dipping directly from the line of inland hill. —

The anticlinal band point is beautifully distinct, the strike is N 6° W & the dip from each side quite regular & well seen from the infinite number of beds in the cliffs which are about 200 ft high. — The dip is from 10° to 20°. — A valley separates the dips (one of elevation) about 300 y^ds wide. —

The appearance of this The line is parallel to the point of Huechucucuy, composed of mica slate. — The appearance of these cliffs is decidedly that of upheaval: Yet the occasional dips from a cause centre: the almost universality extent of this inclination inclined strata: and the following appearance which may sometimes ne seen, show in patches that the strata have been inclined from original [sketch]

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deposition. —Many reefs of mica slate, which we know runs in a N & S direction lie beneath & cause this apparent lines of elevation & opposite dip. — I cannot myself conceive hundred of thin beds preserving their thickness on a slope of 25°. — Neither can I believe that a sloping plane, would cause the deposits for many hundred yards of either side to retain that dip, this [sketch] in a great breadth of strata the same dip. — Again we do not see any dykes, where rocks are visible: on the other hand valley of elevation.

Some way on this side of P. Huechucucuy the presence of [illeg] rock is announced by hard breccia of such rocks & lava pebbles;

The mica slate is such as often mentioned: dip not very regular, where best W 17 S. high angle. — Much however dipped to East & even E by S. — Direction within 17 degrees of N & S. — Few boulders in all places. —

342 verso

Peninsula of Lacuy

Chiloe

Jan.^y 1835

Generally in Chiloe alternations of sandstone & greenish slaty clay

Wood probably converted into iron pyrites. — in patches. — small siliceous veins stem with iron pyrites
(Spec 2543)

formerly land parallel to shells Huechucucuy not horizontal