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Coquimbo to Copiapò

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Charles Darwin

H.M.S Beagle

May 31^st — Owe Capt FR 6 " 5 riales + 2 " 6 Marianos keep & compass — 20 Riales in Quillota 3 Pesos Coquimbo Don Pedro Jose Barrio Potrero Grande Hills with shells

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June 1^st [1835] M^r Lambert, considers at Arqueros that there are scarcely any true veins; that Silver occurs in wedge-shaped masses with Sulp= of Barytes (certainly M^r Edward vein mine in vein) — That [there] — much of S of Barytes without tinge of silver: In short that they are contemporaneous veins (like quartz in mica slate) The disseminated silver in M^r Edwards mine curious — M^r L tells me that masses of native copper without grain of intermixture of silver have been found close to others of silver & although the latter

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often contains mercury (Men. Gen: Pinto Arsenic — Antimony

Sulphur — yet not a grain of copper =

Looking at a chart outside [of] near coast Copper & Gold — inside Silver & inside again Silver & Lead. — M^r Lambert. =

M^r Lambert at Arqueros considers Metallic vein better when close to the stone dykes —

Tuesday 2^d [June 1835] Whole road cones & paps of syenitic-

greenstone & dark porphyry, some crystalline, greenish, more or less granular altered slates or feldspathic rocks with a

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sort of stratification — a small bay with yellow [ferrugin] arenaceous; cemented mixture of broken shells — Balanida & Pecten a bit of silicified bone like intermediate; but a Concholepas capped by gravel = North of Coquimbo plain with Tosca rock = Arrived at Yerbabuena — the road with a tinge of green, just sufficient to remind one of the freshness of turf & budding flowers in the Spring — travelling in this country produces a constant longing

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after such scenes, a feeling like a prisoner would have —

Coquimbo has [inn — hor] our manner of living the universal ones for strangers = met on road occasional troops of mules, only one house after [illeg] leaving Coquimbo —

Wednesday 3^d [June 1835] first part of day over a mountainous rocky desert, like near Quita Conchalee.; — then a long sandy Wretched plain, covered with broken shells, very little water & that bitter saline, streamlets white deposits succulent plants; interior not inhabited — singular mountains of greenstone & syenite having

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saline springs — Many P. St. Julian finch & Dinca Turco & [nest] Tapacolo = First part

Greenstone like 110 ⁰³ & 110 ⁰⁴, more or less granular, perhaps mine generally more feldspathic — nature doubtful — Some of the paps syenitic. —

At P. de Chores, green brecciated rock & some purplish do — structure just same as in Cordilleras — fragments, altered slates, greenish & reddish, some more siliceous, some more felspath: traversed by grand & immense N & S dykes of black hornblendic greenstone; the Breccia near

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dyke, very compact, conch: fracture, pieces blending together, like the paps at Quiliman — decidedly altered but not Porph —

Near Carizal, some granites —

Before a great plain of sand & recent broken shells, & a lowstep of plain with very much Tosca rock with shells showing extent of this formation. Many Diff parts of [round] comminuted shells from 0 to about 200 ft above level of Sea —

Carizal to Sauce

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Thursday 4^th [June 1835] — Continued to ride over desert plain with many Guanaco afterwards across remarkably narrow & deep ravines — at Chaneral a narrow green valley —

At Chaneral section, Tosca rock with Donax & Concholepas, perhaps at higher level than at Coquimbo — covering a coarse Losa, with many pebbles beneath which comes a hardish shelly mass, chiefly Balanidae, of an bright ochry color, [smally] comminuted, cemented & alternating with few layers of a very fine, perhaps aluminous, ochry & sometimes green powder occasional few pebbles — whole bed section very like Coquimbo —

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dip of lower beds, appeared greater than Tosca rock to SE. from an outlying range of hills — I think certainly tilted. = These barren extensive Tosca rock plains very like those near B. Blanca, though there much more grass — here small bushes = it is very singular how so many shells = At P. de los Leones we [had] some granite, which by arrangement of black mica & Hornblende is rather a gneiss — Passing [Quebrada] Onda — we entered a grand mass of fine true Granite hills —

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I noticed here an appearance of stratified granite several times regular alternating — the lowest bed was as general mass, with large black cry of mica — then came — broad 18 ft of white-fine grained much quartz feldspar & black [junctures] above this again common granite, with two or three thin beds. — The lower Main granite had the usual more micaceous black ∠ patches — The lower junction very regular, yet I found few pieces of the white involved; & in upper

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junction of white bed, many pieces of the common (& containing the darker ∠ bits) imbedded in = what confusion — Also further on there was a large vein, which bifurcated & thinned away of same black, as ∠ bits. — All this granite had many patches & veins, of [Euritic] & other granites, many of which died away on each side. —

(N B before entering granite, saw some Tosca rock plain at twice elevation as at Coquimbo) Proceeding NE, we entered

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a grand. mica Slate district — mica Slate, much very contorted like Chiloe, rest more even ground, the thin laminae, little micaceous black — dip general high ∠ 70? to about ENE — NNE by E. = Further in country, granite occasionally appears — In this district some copper mines — The mica slate seems to form a band E of the Granite Hills —

Poor horses nothing but bit of straw to eat, after travelling whole day. — Some of the granite weathers into balls or crusts —

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I believe granite near Carizal is a gneiss —

Friday 5^th [June 1835] Immense number of [Bulimi] like B Blanca —

magnificent spectacle of clouds, horizon perfectly true — coast like most broken parts of Chonos Archipelago: — Mountains covered with tiny bushes encrusted with a gree[n] filamentous Lichen, even the large candlestick cactus of Chile is succeeded by these species — Valley of Guasco, from terraces distant tame snowy Cordilleras; exceeding brown hills, narrow flat, well wooded with willows, valley, certainly pretty. Capt Halls¹ description neutral but I expected such valley as at C. Verd Is^d. — a light shower last May, rain of Coquimbo, a cloudy day here, such envy expressed

¹ Hall 1824.

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three years ago very rainy; flood more injurous than dry year torrents [covering] flat valley with sand & stones. —

In Cordilleras, near [S.] Yeso I saw a shell like those of R. Claro. = Leaving Sauce again came into some granite with copper mines & then again entered the great mica slate district, which we did not leave till we came into a Trappean ore near Freirina [Freyrina] — The mica slate has not a very [extreme] dip; Rock such as at Chiloe is associated with a black micaceous rock, almost like Ampelite & some brown glossy ones & some even compact, little laminated bluish clay slates. — formation very like Concepcion. — many saline

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springs — (is there rain enough for even these few springs?). —

|| Tosca Rock on the Road. — All the mines from description & specimens, appear to lie in the slate formation — || In some the vein is associated with Foleaceous rocks & even Soapstone with thin plates of metallic copper = Soapstone good sign — — much Carb of Copper & some beautiful blue vitriol. —

Saturday 6^th [June 1835] Rode down to the Port¹ — miserable rocky desert little hole. = Contradanca map [and] atlas — the most learned Limenian lady² — King of Londres — View up the valley very striking on a clear day infinity of crossing lines blending together

¹ Guasco (Huasco).

² 'I called in the evening at the house of the "Governador"; the Signora was a Lime[n]ian & affected blue-stockingism & superiority over her neighbours. Yet this learned lady never could have seen a Map. M^r Hardy told me that one day a coloured Atlas was lying on a Pianoforte & this lady seeing it exclaimed, "Esta es contradanca". This is a country dance! "que bonita" how pretty!' Beagle diary, p. 336.

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in a beautiful haze, distant snow mountains clear outline — formal foreground. = At Port there are a variety of curious varying slaty rocks, often very ferruginous either [jaspery] or feldspathic (pounded up & used for furnace bricks). sometimes quite Porph. with white crystals certainly seeming to belong to mica slate, — for such is found in valley [perfectly] characterised, this rock is much traversed by dyke & masses of Trappean rocks apparently belonging to mass of hills mentioned yesterday. — dip to about SW by S — but in other locality to ESE. = Plains of valley more strongly marked than at Guasco

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highest one, much greater elevation, some have gravel so firmly cemented into a rock & layers of white clay with obscure vegetable impressions = pebbles white — washed on upper plain = near Port in one of the lower plains a very soft sandstone — on the lowest plains some comminuted shells = I could trace on northern side, including plain of river (which in floods is all washed) 6 plains, & in other place (5) — the upper ones are extensive & one of the lower ones also rest mere lines on the escarpment

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one plain is developed in one spot dies away leaving line of knobs till no evidence remains — I saw Mem. yesterday Tosca rock in my journey — Saltpetre produced in mouth of furnace. — All these hills highly auriferous —

Carrancha — T[h]enca — Loyca¹ (Black & Gold finch) Dinca² Chingolo³ — Furnarius — Avecassina — little Grey Bird of mountains — Blue finch with white dot in tail — no Chingolo — C[aracara]. Raucanca⁴ white tail Callandra

Sunday 7^th [June 1835] Staid to rest animals. Ascended hill behind

town. Beside plain of river there were fine other broad distinct terraces, the

¹ Molina's name for the starling Sturnus ruber, see 'Ornithological notes', p. 214.

² Chilian name for Fringilla see 'Ornithological notes', p. 251.

³ Specimen not in spirits 1615 in Zoology notes, p. 394; listed as Zonotrichia matutina in Birds, p. 91.

⁴ Specimen 2029 in Zoology notes, p. 230 and 'Ornithological notes', p. 238; listed as Milvago albogularis in Birds, pp. 18-21.

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lower ones on the side 2 or 300 yards wide & in places much narrower, (river is removing some) on that escarpment which faces, there is between 3^d & 4^th from top, another which can be seen for about a mile. — making 7 with bed of river The two upper plains where I ascended are very broard, the upper one runs far up valley very extensive — lowers quite parallel — where 7 plains there is in one spot one escarpment — where I ascended, there was pretty clear trace of another terrace but not extending far is not counted.

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On the Hill where I ascended an imperfect slate (with mines) laminae irregular general N & S directions — 5 steps (beside bed) may be here considered general [as] 3 in Coquimbo —

Freyrina small village of white houses —

Monday 8^th [June 1835] Road up to Ballenar; view when high mountains obscured by clouds very like S. Cruz. Some of the lower plains expand much near Ballenar Judging by color of hills, the P. Breccia formation begins a little to the E of Ballenar — called 10 leagues Some [Salitrales] on these plains

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Tuesday 9^th [June 1835] Staid in Ballenar considerable town just sprung up, owing to mines — food brought from South. — Hear of fossil wood on other side of Cordilleras. = Found Terebratulida in the cherty rock as at R. Claro — (V Specimen) doubtless same as all the specimens from Guashco Alto — & the shells which I saw at Freyrina

— I hear of part of ammonite = shells must be excessively abundant at Guasko Alto — Silver mines in all parts there — I can see the P. Brec about 2 leagues E of this place. — At

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Ballenar 5 plains magnificently developed besides valley — thickness of highest I should think 600 ft —

Each plain in part very broard — Above highest plain, there seems another with no distinct escarpment — but outlines — extending grand horizon plain to north = Most interesting view from steps north of Ballenar — grand escarpment. East — Hills of Granitic rocks — with these terraces (like Chonos) narrow green line of valley =

Patagonia a garden compared to these plains — many absolutely barren — yet dormant seeds — wait for wet year. =

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Wednesday 10^th [June 1835] Started for Copiapò — The highest plain of yesterday north of Town is backed by escarpement, must have formed a bay — there is no higher plain — Very extensive stretching far to mouth = We entered obliquely the P. B. form — apparent extensive escarpement with East dip — but found on margin of plain W E a slope to W — not scarcely visible — much contortion & irregular dip — each escarpement of a [illeg] seems independently stratified = rock chiefly finegrained red Sandstone — Crystalline specks of Carb of lime & some little

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[coarse] associated with a great deal of the calcareo — cherty bed — with bits of shells — some little purer limestone & softer — is evidently grand formation — seems high in the system — We rode for some time on these irregular [skutey] hills — We then came to some low hills of a slatey rock with dip to E 60˚- 70˚ — in places silicious clay slate, others Talcaceous — with occasional modules & crystals — varying character pale color — This is succeeded

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to East by extensive range of true granite Hills; two sorts of granite are in distinct mountains close together, common & a ferruginous quartzose little mica, closer grained kind — Beyond this escarpement of true Cordilleras of P.B. A very desolate but not quite uninteresting ride, followed damp course of [bank] about ½ league up nice little stream fine wood — two or three in road [Ranchitos] Indians — Many donkey — eat wood — nothing for poor horses = contrast of

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splendid weather & utterly useless weather —

Thursday 11^th [June 1835] Travelled for 12 hours, never stopping —

Poor horses wonderfully fresh — nothing to eat at night: — uneven country — Various shades — much prettier than a forest. = Met silver stealers. — Geology (not being able to stop) unintelligible — The true P.B. seems very comparatively rare — there is a singularly long & regular ridge with E dip — composed of arenaceous Limestone (105) ? Very slaty structure with Terebratulata & fragments of shells — [others] with compact siliceo rocks (106)

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such as before. — its connection with P.B. I do not know — a separate slaty ridge with Terebratulata, it occurs at considerable absolute elevation. =

Friday 12^th [June 1835] plains of gravel — 1000^ft above the valley of Copiapo = Arrived before noon at Hacienda of Potrero Seco =

History of association prevent speculation of Pastures Mules — Little

Saturday 13^th [June 1835] Geology in this situation of Los Hornitos very complicated — there is a

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Band (Quebrada of Chanuncillo) of the Gypseous strata & its superior strata with an Easterly dip, in parts however there is an [interline] dip & (variation in direction E) on borders of valley, in about the band of Gypsum — The strata dip at 45˚ & upwards I obtained following section but not very perfect. —

(1) Purple sandstone, or rather conglomerate large rounded blocks — cement not Porphyritic, but slightly crystalline. structure large rounded pebbles, even boulders if various porphyries, ¾ of them

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a very pale purple porph with small Porph Cry of F., conch: fracture

— just like neighbouring hills of injected rock — veins of Calc spar.

— considerable thickness — This grand bed contains [illeg] 3 thin strata of Black coarsely laminated Calc? Clay Slate (107): 2^d bed of light green (108) altered argilla bed, slightly nodular structure.

3^d. Purple sandstone, slightly crystalline structure, also nodular in small degree (109) —

4^th compact dusky green, finely brecciated

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feldspathic. altered. Arg. rock (110)

5^th Gypsum, very impure, thin layers, sometimes little contorted, (lowest ones alternate with a laminated green rock as 4th) no selenite — rock porous, layer of earthy matter — 20 ft thick —

6^th as 4th dusky green gypsum —

8^th — a laminated green rock with some layers of siliceous rock (111) veined & specks with Carb of Iron? There is some white rock (113). coarsely veined with this ferruginous rock. — Above this there is a great mass of rather brightly greener rock, with a remarkable nodular or concretionary rock, of all sizes

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strata composed of balls —

9^th a grand thickness of Ferruginous coloured (112) soft very much laminated crumbling dusty [dirty] pale green or brown ven Argillaceous schist — laminae sometimes contorted — crumbling into angular bits = sometimes like dendritic markings manganese veins of Calc. Spar: masses of white patches, few of white rock (113) & some much layers of the Carbonate of Iron & silicious matter (114)

— These beds remind me of those of Hornitos & Puclaro. Above

10^th Above a mountain of dull

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green & sometimes purplish (115) sandstone very compact, with very many Calc-spar veins — & some metallic (distinct of silver gold & copper) — owing to compression of dips could not trace any more = All these rocks, which I call Sandstone have a smooth compact fracture, & are only called sandstone because they show fine brecciated structure =

These formations dip Easterly towards a number of grand hills which appear to have burst through & uplifted them — they consist very pale purple or

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pale clay stone porph. (clearly melted) small crystals of Feldspar. —

Sunday 14^th [June 1835]

116: 117: 118 — 3 varieties of lowest Lava or Porphyry.

119: 120 The great field of pink Lilac lava generally more porphyrytic

121 — White rock above do lava

122 Concretion in this white rock

123 Gypsum impure

124 — Rock which alternates with do

125: Commonest rock of great upper bed

126 — Part of do —

127 — Thin bed or layer in do

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128 — Veins in above strata of Carb of Iron? —

129 — The conglomerate above the Lilac lava & all the X pebbles in do

I examined the a Quebrada of Chanuncillo, del Hornito. The bed of last section wh is lowest or the conglomerate I find 2-300 ft thick; the basis in places certainly is rather porphyritic. (129) —

The pebbles from size of fist to that of head very numerous — examined very many all porphyries. the greater part like the injected of Hill of yesterday specimens with [crys] exemplifying these (NB one of these, by mistake, is part of base of matrix)

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it is manifest, the rock of pebbles was originally a porphyry = difficulty explained by an underlying bed of porphyry which is a Lava — color pale lilac — conch — fracture — structure rather laminated, few crystals — some highly sonorous (119. 120) & on grand scale conformable to upper bed of conglom — with some irregularities — lower edge also parallel — Between this & the Conglom. there is a varying thickness of quite white rock (121), which seems much

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altered hard, [harsh] — nature doubtful — [smally] brecciated with little purple spot — remarkable by containing dark rust color. many concretions, I judge from form, globular pear-shaped (like Calc: Sandstone) of some Lilac Porph as Lava stream (122). — This Lilac Lava [is perhaps] 150-200 ft thick, rests on what in places appears like a bed, in others seems to blend with lofty Porph: Hill, which will be seen is axis of anticlinal band. — The Lilac Lava varies slightly, but this lower bed is always of darker color

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& consists of very many & curious kinds of crystalline rocks (116: 17: 18). — The central parts of Porphyry [probably] contains [paps]& part of curious green & brown Porphyry. —

(Mem. pebble of white rock with other pebbles in conglomerate bed). —

With respect to other beds above the conglomerate I find them subject to much variation, up the ravine. The black laminated calc clay Slate increases much in quantity, is very ferruginous in external fracture (like rock of Portillo) — large plates — some brown all way through. — Alternate repeated with the red Sandstone — & green beds which are less

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E A B Porphyry Lilic N Sandstone congl Argillaceous beds & gypsum Gravel Conglomerate Lilac lava Dark Lava Porph B A Porph X Lilac Lava Conglomerate &c &c G W

abundant — Also these such strata alternate & form part of the [hardened] clay & carbonate of Iron beds — Those which show bright yellow in the mountains cannot be short of 800 ft above exclusive of lower part of Red Conglomerate. (NB) generally some slate is also below the conglom: & lava =

All these laminated ferruginous beds soft, are proper to Gypsum — in this ravine the Gypsum rather dies away — & becomes very thin — The

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Gypsum, on North side of valley (where there is a mine) almost all the yellow beds abound in thin layers of Gypsum — rather a Gypseous Tufa — some layers are inch or more thick, generally thin & impure, with calcareous & these argillaceous Laminae (124. 123) Above these yellow Argillaceous beds there is at least 1500 ft thick of the rock which I improperly call Sandstone — its color & structure vary, but smally, a little finer or coarser, a little more or less green, purplish or brown. — The first & last most common. — Structure rather nodular

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is remarkable by a thin stratum about 80ft apart, each about 18 inches thick of a hard, black, ferruginous rock — which may [be] seen in middle of these beds running for miles, & projecting upwards (127) — I believe the great mass — capped by a yellowish mass & this by a purplish — but the exact limit or superior bed is difficult to determine on account of great confusion produced by the [form.] shown at (z) in section —

All those beds dip from 30-40 to ESE — the band of upheaval is very great, may be seen for

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for about 15 miles in a N by E to NNE & SSW direction. — its anticlinal dip is seen on other side of Hill (B). not dipping to WNW but to WSW. Not so highly elevated, I saw no more of this dip = The strata are thrusted as shown at (Z), apparently by the posterior elevation of the still higher line of Porph Hills Mountains (A). = I should think (A) the origin of Lava — it seems that old Volcano point of subsequent upheaval. —

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About 2 miles to North of Hill (B) an important observation. — The Lilac Lava is found here as everywhere conformable & beneath grand mass of conglom — (covered by the great gypseous form already alluded to) instead of resting on a perfect porphyry. it rests on a conglomerate such as that which covers it — but the pebbles are of a darker tint & not of Lilac Porph, but of various kinds — Now in Hill (B) there is no trace of such structure, only small trace of being a bed parallel to Lilac, so that

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I thought it Lava which blended with its origin amidst curious Porphyries — now it seems clear, that the hill (B) perhaps forms [part] of hidden granite, has so altered this bed, that its true character cannot be recognised. I suppose these beds upper part of P.B Formation, or those masses which support the Gypseous Formation = I urge this as a very important instance, as all the beds can be traced over whole country & there can be no mistakes. —

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Hill (B) is [marbled] with strata, with high dip — bare where facing the valley — dip smaller where the lower beds are seen to be conglomerate — In all these conglomerate pebbles can be easily separated no blending of parts = Can the white Bed above Lilac Lava baked volcanic ashes ? =

Monday 15^th [June 1835] Rode up to Los Amolanas valley or rather Quebrada very narrow — very much Alfalfa — river size of large muddy brook — for 30 years never reached sea — now does — send up guards — plenty of snow now secure —

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E Gypseous Sandstone P. B. South side of valley Dark Porph 131 Syenite Green Porph Lilac [Porph] Posterior elevated W Eugenio Matta Potrero La Punta

After passing for some time between hills of Lilac Porph — (Mem. valley formed by removal of fractured strata between great irregular cones — ) we came to some green & dusky [base] with few crystals of feldspar & specks of Hornblende — Then there are paps of a finely granular syenitic greenstone

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& then a great central formation of whitish syenitic greenstone (130) specimen smally crystallised, generally much coarser— This rock is capped & succeeded by some black fine grained micaceous (131) rock which it has penetrated with an extraordinary number of beautiful dykes of a white color consisting of well cryst feldspar with few specks of Hornblende — These dykes on large scale may be seen traversing the succeeding hills to the distance of the two or three

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miles & proceeding directly from the syenitic central grand mass — with the syenite in one spot there is a true granite, white as usual. —

The syenite mountains are succeeded by grand dusky coloured Porphyry Hills, which on eastern part, show signs, which gradually become more certain of highly inclined stratification to SE or more southerly. — These consist of the true P.B, although much altered & are of great thickness perhaps from 1500—2000 ft —

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such beds, doubtless come below the the conglomerate of yesterday. — To the East the slope of mountain was not much interrupted by a remarkable fault, which brought a small irregular dip to W of the upper gypseous in contact with the SE dip of interior P.B. = (at La Punta the syenite is well developed) It appears looking at structure on each boundary grand mass of mountains have [fault] up, posterior to formation of [Gypsum]

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Formation. = There is a grand mass of mountains, composed of bright red standstone (a rock which deserves its name) 132, threaded with veins of Gypsum associated with some green & some black laminated rock — but general tint of hills bright red as at Potrero Seco. bright yellow; clearly same formation = Subsequent to the irregular dip towards the P.B. we have

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the dips as in section of those upper formations subject to much irregularity traversed by many dykes faults & metallic veins — This reaches opposite to Eugenio Matta — further to Amolanas — am not sure — This is on S side of valley — on North side the first dip with fault is clear, [beyond] which from faults & compression, there is no [undisturbed] structure — I see the two side of valley seem in dip in [the] parts to correspond —

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abundant silver mines in all this district. = Gypseous formation like Incas bridge, except that veins instead of grand masses=

Tuesday 16^th [June 1835] Ascended to where the famous shells are found — Found there is a grand range with a WSW dip 30˚—40˚ = Hence in the valley which here runs N by W & S by E is a trough between two range & the consequent difficulty is explained. — The shells excessively numerous — an enormous quantity of Gryphites in lower band & above thousands of the univalve — very numerous Terebratulæ

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& bits of oysters & some Pectens in all parts = They occur in a jet black thinly stratified [aryllan] [shattey] thin intermediate strata) calcareous, argillaceous rock (133) conch fracture; although on fracture so black, surface weathered [half] brown, hence whole mountain precisely like that of Portillo. — Where bits of shells very numerous there are strata of a greyer calcareous rock (134) — These beds are of great thickness, contain very many strata of a yellowish fine grained siliceous sandstone like (135 & 136) — There was one stratum of purple conglomerate

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Besides grand, thick, conchiferous layers found two others = Some of the black rock is a little paler & bluer, some with tint of green. — All weather white — Some upper strata were lined with [number] contemp large veins of Gypsum —

Specimen of black rock two crystalline. — Whole mountains very remarkable by the unparallel number of parallel, zizag dykes of all sizes & forms: of very various rock almost all Porphyries some approaching to syenitic greenstone. —

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But rock (137) is most common — many crystals many an inch big — base varies from black green to white — 138 is other common variety. — This must have been close to volcanic forces — as many lines for dykes as strata lines = Examined same great chain — on South side of valley the lowest rock is a purplish black coarse fracture, few crystals Lava Porphyry — conformably covered — & suddenly by coarse conglomerate, quite as coarse (no trace of cryst struc in matrix) as at Pluclaro & R Claro

Not work of dykes. more cracks filled up, no effect on strata

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color pale, sudden transition shows lower is true lava — bed some hundred feet thick lower half whitish, upper pink — much [marly] harsh agglutinated coarse sand with current cleavage not parallel to strata — This is covered by grand mass of yellowish siliceous sandstone (135-136). Softer pieces used for sharpen hence name Los Amolanas — This rock contains some band closely cemented with it of white conglomerate some

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of purple — Also some of the black Calc or Clay slate — I believe however the grand mass of latter rocks comes over this, then Red Sandstone with its Gypsum? — Parts of white sandstone hard small white quartz pebbles & seen one piece of quartz mica &c hence origin — like [Porotas]. —

The yellowish sandstone in parts great part was greenish & approached character of the green rock of Potrero Seco in compactness. I imagine it represents, as this black

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Calc rock with Conch fracture does the [more] laminated black rock of do seen in both in cases connected with Gypsum — The collection of fossils very interesting in itself, & as connecting all the localities; all appear to be about age or little older of lower Gypsum = The Sandstone & Terebratula & Gryphites show R. Claro same age & the coarse conglomerate being here inferior removes doubts about modern age of conglom there & Pluclaro — At R. Claro either great streams of lava prevented Gypsum, or removed

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or upheaved previously = at the period where these shells great similarity down the coast — great lateral volcanic action — As Uspallata a little later = (No terrestrial lavas in Chile — except perhaps ? [Canqueros??] & Portillo ?? ) I suspect there is great replacement & dying away of the different strata of this period = on some of the large univalve — oyster & Serpula adhering — a bit of small Ammonite = In the conglomerate Porphyres & some jaspery & red sandstones. — where shells conglom's non-porph =

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Wednesday 17^th [June 1835] (139) altered Sandstone or Lava? (140) matrix of conglomerate (141) Lava beneath do — (142) Lava above Sandstone. (143). Syenite greenstone — (144) variety of mica slate. remarkable uniformity of syenite greenstone in whole range — S Fernando — Copiapò =

It appears to me that all the mountains about Amolanas might be called one range with westerly dip: irregular that is often double or even treble connected by faults [three escarpments separated by faults], sometimes so sometimes one single = We have seen yesterday that the bed beneath

[page 59]

the Conglomerate is a Lava Porphyry — The rest of beds consist of various purple & some green more or less Porphyry rock — beneath these came a stone, nature of which I am not certain blackish purple fine grained perhaps altered Sandstone (139) — beneath which came a stratum of coarse conglomerate not the least blended — matrix crystalline 140? — Besides Porphyry there was one pebble of Granite. — a very rare occurrence — beneath this we had crystalline fine grained porphyrys all of dark colors (141). & after some

[page 60]

few more such strata true Granite. I do not think all strata are here seen, but certainly a great thickness, only very partially examined: contrasted with S. (I found some fragments of pale-coloured true ∠^r Conglom blended Porph Brec) very little true P.B. much more Lava (for from coarse strata of the Conglom so near Granite clearly all the Porphyries which I examined for great thickness are true Lavas)

[page 61]

This section is where Quebrado of Jolquera commences — The Granite traversed by numerous blackish purple dykes — is connected with Syenitic Granite — much (white Feldspar much Quartz & specks of iron rust) — This is the axis of the grand range — The valley (Z) turn up N. with little Easting; on West side the great mountain of Protogine (white) capped by Purple rocks — at its base dipping right on it there are some thinly stratified Sandstone (precisely as before with some of the black rock with the Univalve — Gryphite Pecten Ostrea Terebratulæ

[page 62]

Mica slate Syenite Much thicker Syenite Porphyry D (Z) A little way to N this is not seen (C)

& veins of Gypsum = This is capped by streams of heavy nearly black Lava (142) remarkable by containing balls rounded or oval of still heavier kind — very hard, egg to cricket ball. — The sandstone varies from 30 to 60 or 80 ft rest on Purple Porphyry full of crystals of white Feld

[page 63]

Porphyry W Granite Lava Sandstone with shells Porph Lava Granite Porph Conglom Porphyry Conglom Siliceous sandstone Shells Blackstone Gypsum ? The Amolanas range double in places

This lower mass is clearly divided into several streams by bands of parallel harsh Porphyry highly amygdaloid — This ascends on west side & lies on a range (parallel to Granite) of true coarse grained syenitic greenstone crossing this obliquely in NE — very broard

[page 64]

good deal of syenite has also mica (143) true Granite character ∠^r spots, traversed by paps of diff: kinds some true Granite — (NB some of the Porph^s with green & yellow spots owing to Epidote): On the East side of the Syenite, a considerable breadth of micaceous slate, with large Quartz veins. (& Granite dykes), in central part contains much green slate (144) containing Feldspar Mica — Chlorite ? with Quartz parallel veins — also some irregular masses of a ferruginous quartose slates

[page 65]

cleavage about N & S — dip not very regular chiefly E — bent or curved on large scale. = (great fault in this country in [Panilas]) I should think stratified rocks at Amolanas attained thickness 5—7000 ft / at least. about 3 grand divisions —

Thursday 18.^th [June 1835] (145) Lowest Grey Porph: (146) Lava compact with little red crystals (147) Lilac Porphyry — (148) Amygdaloid Porphyry. (149) Variety of compact Porphyry above latter (150) Red intermediate sediment strata (151) White coarse sandstone volcanic particles

[page 66]

The mica slate is succeeded by Porprhyries, the line of junction appears parallel to stratification. Then a narrow slip which buts up against hills of Syenite with occasional grains of quartz — But further North, these purple strata, little inclined to E extend a good deal into central Cordilleras, but owing to [Northerly] direction of Quebrada did not follow it = Between mica slate & syenite highly inclined — The purple strata consists of Syenite at least 2000 ft thick.

[page 67]

??? Porphyry Syenite Porphyry Mica Sl[ate]

clearly stratified: one of the lowest beds is a grey rather harsh Porphyry with a good many crystals of Feldspar (145). — Above this which we have a great thickness of a compact green — mottled Lava (146) which upper part becomes purple waving red water line separated by bright red sedimentary bed like (149 150) from Lilac Poprh above — This (146) Lava [assumes]

[page 68]

often many red little crystals like (149) — Above this grand thickness of Lilac Porph — harsh few crystals of Feldspar. often this substance arranged in short waving lines (147). Above this many kinds — In other section found quantities of thin beds 12-20 ft of dull purple Lava & Lava (149) — separated by parallel bands of Amygdaloid rock (148) mass of crystalline amygdaloid

[page 69]

stone. — these are separated from each other narrow bands 6 inches to 12 inches of baked bright red sedimentary substance (150) — One bed about 20 ft (covered by 8 feet of latter substance & then the purple again the purple Lavas) of white sandstone or rather bits of volcanic rocks firmly cemented. Found some many fragments of true green & purple Porph Breccia — so one stratum does occur in these Purple rocks —

[page 70]

Friday 19^th [June 1835] The strata are broken up rather by hills, whose longest axis N & S rather than a chain — if the line of any of these fracture are traced they will not be found far continuous. = The purple rocks seems to extend far in the country Andes: I examined them in many places & found them nearly all Lavas with very thin separation of sedimentary rocks I found one cliff at least 300 ft. of hard rock crumbling fracture, entirely composed of such — chiefly a mottled sort, specks of green

[page 71]

white & red (152). it contained numerous thin layers such as (151) one about 20 ft as (150), another equal thick of 153 — This mottled rock contained some large round pebbles as big as mans head of various Porphyry purple, & its tint varied in its shades — lower part alternated with purple ferruginous Lava = in The all the Porph^y much amygdaloid, some little concentric structure, obscure traces of columnar: It is very interesting

[page 72]

finding grand Volcanic Lava formation of age of Ammonites &c &c separated by what must have been true conglomerates & Brongniarts¹ name for Volcanic sandstone: = (NB fossils of Falklands of hot country??) I took much trouble with formation of Mica Slate — (the green slates external) the other beds certainly are of less crystall structure & ferruginous but seem upheaved bodily through the Breccia formation — The commonest sorts of Porph. Lava have the little red crystals

¹ Alexandre Brongniart (1770-1847), Professor of Mineralogy at the Natural History Museum in Paris and co-author with George Cuvier in 1811 of the classic geological description of the Paris Basin. The specific reference may be to Brongniart 1833 which was in the Beagle library (Correspondence vol. 1, p. 558) and is referred to in the geological diary (DAR 35.396).

[page 73]

All this part of valley of Copiapò highly metalliferous, no where have I seen such confused stratification, or so many dykes yet rocks not so much metamorpho = Returned down the solitary ravine to Los Amolanas, difficulty in descending steep mountains. Valley runs up so much to North Valley all formed by connection of low [points] in lines of upheaval (as seen by inclined dip on each side) enlardeg¹ by water () [here] generally of this form =

Saturday 20^th [June 1835] 154: 55. 56 — Silicified wood from Conglomerate — 157: 58 Sandstone of do Conglomerate: 159 Shell above do — 160 Green dyke in do —

¹ = Enlarged. An unusual transposition of consonants.

[page 74]

Replacement & causes

It appears to me general that one point of injection is more subject to a quite different class of do. than any other point = Like same volcano different lavas, upheaval on same part of strata: Here where much Gypseous & super Gypseous slate gold — silver — copper & micaceous iron — with respect to Paniza — very many faults, where so similar beds, hard to discover, no external sign being present: The R. Claro Terebratula is found also here: — Noticed that some of the black rock becomes so thinly stratified & argillaceous, that it is a complete clay - slate. — & some

[page 75]

of the silicious sandstone a coarse one with fragments of shells — The black rock & sandstone replace each other without order, perhaps the latter former rock superior — In same manner the black rock with Gyspum & the Red Sandstone with do replace each other. — Examined to day the supergypseous an immense thickness 2000— 3000 ft thick almost entirely Red Sandstones & Conglomerate (difficulty owing to faults as before mentioned except by hammering every stratum — Above the gypseous rock there is an immense

[page 76]

mass of conglomerate, pebbles small — Size of egg cricket ball, few rather larger thickly packed in lines interstices, & occasional seams, of red sandstone (157-158), whole beds of this colour — (some parts purplish) pebbles are easily separated, almost all Porphyries, or crystalline rocks, & some reddish siliceous rock = This bed many hundred feet thick (all westerly dip varying about 30˚) remarkable by thousand of great blocks of petrified Dycot wood, whole surface strewed with pieces — (hill due west of house of

[page 77]

Hacienda found several in situ, either in the Sandstone seams or amongst the gravel — horizontal, one had about 8 ft in length apparent with strips of branches apparent; another had a diameter of 5ft. perfect silicified to centre, excepting in few concentric structures of wood not visible centre generally marked by [tissue] of Quartz veins — Most like wood of Hornillos — very black or white siliceous, patches & veins like variety of mica Slate, mistook it even after examination, little of the structure

[page 78]

remains; harsh & brittle, tree easily falls to pieces — enormous rock, one must have belonged to tree nearly 6 ft in diameter — What an extraordinary prop.!! Above the Conglomerate, with alternations, rather a finer grained red Sandstone, 2-300 ft thick upper seams impressions of many shells, amongst which I clearly recognized Gryphaea, & the univalve & many of Bivalve (159) above, grand mass of Lilac Porph, am not quite sure, believe if Lava may be injected

[page 79]

although nearly parallel across whole mountain, — yet do not feel quite sure, R Conglomerate & [B] Sandstone (near shells one seam of black rock) up to top of mountain; I believe chiefly latter could not reach it — conformable; these grand mass of strata appear in country, [now] [commonly] removed, only saw the cream-coloured mountain capped in one place by Red lead Sandstones — Whole mountain traversed by black Porph — dykes white Feldspathic (all of which I believe like from Syenites)

[page 80]

& green laminated dyke (160). remarkable as identical with one of R. Claro, & on grand scale, having a sort of of water line or stratified structure. — No one can imagine such glorious confusion —

These beds correspond to compact-misnamed sandstones of Potrero-Seco; The red Conglom &c of Pluclaro (hence surprise) — Hornillos — Uspallata & Conglom. (upon sandstone) of Portillo were formed at period of great volcanic agency amongst luxuriant islands — siliceous springs, after great gypsum deposit, Some from Islands great diversity of

[page 81]

mineralogical nature — age from fossils greater than what I supposed at Uspallata = Now there is good comparison with Humboldt = I strongly suspect the whole & inferior Gypseous Formation not very ancient: Staid whole day at Hacienda—

Dom[ingo] Sunday 21 [June 1835] Earthquakes more frequent on this the hilly side of Andes than at Mendoza — S Juan —

Returned to Hacienda of Potrero Seco

Valley of Copiapo a mere island 12000 inhabitants, three times have removed (owing to mines)

[page 82]

The section of the country from Los Amolanas to Potrero Seco presents I think only one line of Escarpement besides the grand one — & it is the upper or gypseous parts of this, near the Southern border of the mass of Syenite & Porphyry Hills, therefore that part must not be so much represented in the section of the country —

Monday 22^d [June 1835] (161) Laminated, calcareous, arenaceous rock — (162) Calcareous more so associated with do (163) a sort of Hone

[page 83]

stone (164) a soft purplish argillaceous stone (165). Stone feldspathic associated with (166) more siliceous, Piedra [Carlo] of Capperosa — (167.) - (168) Gypseous earth (169) Ochreous do — chief part of vein —

I believe dykes in Chile run in every form & direction = If 30 parellel lines were drawn in this district from E to W I do not believe line of parallel fractures would extend in few parts to above three of them: = Descended the valley to town of

[page 84]

Copiapò. I see the anticlinal or East dip on E side of Hill B of Lilac Porphyry — is a mere Local Phenomenon The dip strike run into a point on south side of hill, the valley being on the north: The form is such as that described on a grander scale than at Uspallata — & such would be the form produced in hard layer upheaved by rounded hill — The Lilac Lava & under bed of Conglom or

[page 85]

Local P Breccia D Gypseous E W

D Porphyry very obscure, W dip, (E) Gypseous rocks, dip to E — but various — succeeded by either W. dip or nearly horizontal

Crystalline rock ( ؟whether equivalent?) is succeed by a broad belt of the PB Formation, there is a little true blended rock, but much pale purple Conglom & the compact Porph. Lavas. — I think greater much

[page 86]

thickness than in Cordilleras. There [to] W. blend into hills of Porph — where stratification dies away, & perhaps succeeded by very obscure dip to W. — Then comes the same line of hills which was so remarkable in journey of the yellowish Calc sandstone (161.) associated with other varieties (162 double) These are seen to overlie an immense mass of beds some absolutely verticaly — others highly inclined, general grand dip to East of pale cream colour, white, dark

[page 87]

& pink beds, very thinly stratified, from much equal strata, varying stratification — excised valleys, & slopes, abrupt of hills give a marked arc = these strata consist of the black rock, a sort of Hone stone (163), layers of [alternate] [Yeso] & the Argillaceous soapstone (164). purplish or whitish — clearly these are Gypseous formation — whether the overlying laminated Sandstone & limestone? with corresponds to red

[page 88]

Conglomerate is doubtful — I think however from remarkable geographical line & frequent valley it is the upper bed of country =

(NB the grand plain of Gravel 2-400 ft thick which contains is broken formation at Potrero Seco very remarkable) — (NB in the P Brecc formation there was one, hill of Lilac Porph injected.) =

[page 89]

The grand band of this formation is succeeded by an W dip in some few spots, more generally by a broad mass which reaches nearly to Copiapò, which is either nearly horizontal, or irregularly contorted by various hills & masses of injected rocks. — fine-grained, greenstones &c &c (NB. true greenstone very rare I recollect no such hill excepting at Campana & few dykes excepting some fine grained sort & the Porphyritic sorts) In one of these hills, which has been contorted

[page 90]

(NB Minerales of all sorts in these hills gold of gypsum age silver & copper) the upper strata composed of a greenish Feldspathic (165) associated with more siliceous (166). — in the mines of Sulph of Iron — The vein is very broad & composed chiefly of yellow ocherous [Cault]. (hence name Tierra Amarilla) (169) associated with ferruginous Gypseous (168) is not much inclined & parallel to certain marks in hills — most obscurely stratified (so not quite certain) much sulphate

[page 91]

of iron in Atacama — This Sulp of Iron associated with Sulph of Copper & gypsum & other sandstones (167) which has not so much of the Capperosa for which it is worked When reading Lyell, often said there ought to be Tertiary strata in other parts of world of the Secondary period, although in Europe from his hypothesis there could not be

Tuesday 23^d) [June 1835] Copiapo seated in broard plain like the valley of Aconcagua (for 25 years only, 2 Governors who have reigned

[page 92]

their proper time) — Town of Copiapò miserable, so often shaken down by earthquakes I suspect the four grand line[s] of upheaval of tolerably regular — the mass of syenite & porph Hills of Potrero Seco have burst up in Synclinal spot —

Wednesday 24th [June 1835] } Copiapò
Thursday 25 [June 1835]

[page 93]

Chaneral Bay, Very fine grained Greenstones marine shells scattered on surface. Also brown quartz rock

Immense quantities of Oysters in strata in English Harbor N of Copiapò

Compact & slaty siliceo—Feldspath lead — coloured rock? at

Lavatan: Mem:

[pages 94-131 blank]

[page 132]

[top of page excised]

culpeu¹ — pupil round — destroy immense quantity of poultry —

Molina's account²

¹ Specimen not in spirits 3187 in Zoology notes, p. 411; listed as Canis magellanicus in Mammalia, pp. 10-12.

² Molina 1794-5, 1: 330-2.

[page 133]

of Boldness true — Bark exactly like a dog when chased — so that I did not know — very heavy animal —

؟ I suspect the young of Caracara Raucanca — is brown all over.

Carranch infrequent at Guasco —

؟ Exists at Copiapò —

[page 134]

Sandstone

115 Red compact

114 ferruginous [cast of iron]

113 [whole]

112 ferrugi soft laminated clay bed (Sp),

nodular strata of [SB]

Laminated G. bed

111 with some siliceous ferruginous veins layers

G Dusky green sp

[Gr]

110 Dusky [Gr]

109 Purple sp

108 Light green Sp

107 (Sp) Purple conglom with 2 layers of }(give) thickness. Black laminated Calc. Slate

103

[pages 135-136 blank]

[inside back cover]

Pills

Cigars

Maps

Letters

Pen

Beechey¹ says that Humming Birds stay all winter in N. California —

[Cerro Bermida] 3 leagues from Copiapò

[Eribase] — Pueblo de los Indes 3 Hermanos

¹ Beechey 1831, 2: 82. This reference was copied into 'Ornithological notes', p. 252.

[BACK COVER]

 

Textual notes to the Copiapò notebook

[IFC] 1.7.] Down House number, not transcribed.

88202327] English Heritage number, not transcribed.

11] added pencil by Nora Barlow, not transcribed.

[37] sketch perpendicular to the spine in right margin.

'A' and 'B' deleted transposed in ink.

[44-93] pages written perpendicular to the spine.

[53] Not work…on strata] added heavy pencil.

[62] D] ink.

(C)] ink.

[74] Replacement & causes] written over other entries on page.

[93] page written perpendicular to the spine, in pencil.

[131-2] top of leaf excised.

[135-6] leaf partly excised.

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