登陆注册
5193100000131

第131章 NORTHERN CHILE.CONCLUSION(1)

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.

VALPARAISO TO COQUIMBO.

I have already described the general nature of the rocks in the low country north of Valparaiso, consisting of granites, syenites, greenstones, and altered feldspathic clay-slate.Near Coquimbo there is much hornblendic rock and various dusky-coloured porphyries.I will describe only one section in this district, namely, from near Illapel in a N.E.line to the mines of Los Hornos, and thence in a north by east direction to Combarbala, at the foot of the main Cordillera.

Near Illapel, after passing for some distance over granite, andesite, and andesitic porphyry, we come to a greenish stratified feldspathic rock, which I believe is altered clay-slate, conformably capped by porphyries and porphyritic conglomerate of great thickness, dipping at an average angle of 20 degrees to N.E.by N.The uppermost beds consist of conglomerates and sandstone only a little metamorphosed, and conformably covered by a gypseous formation of very great thickness, but much denuded.This gypseous formation, where first met with, lies in a broad valley or basin, a little southward of the mines of Los Hornos: the lower half alone contains gypsum, not in great masses as in the Cordillera, but in innumerable thin layers, seldom more than an inch or two in thickness.The gypsum is either opaque or transparent, and is associated with carbonate of lime.The layers alternate with numerous varying ones of a calcareous clay-shale (with strong aluminous odour, adhering to the tongue, easily fusible into a pale green glass), more or less indurated, either earthy and cream-coloured, or greenish and hard.The more indurated varieties have a compact, homogeneous, almost crystalline fracture, and contain granules of crystallised oxide of iron.Some of the varieties almost resemble honestones.There is also a little black, hardly fusible, siliceo-calcareous clay-slate, like some of the varieties alternating with gypsum on the Peuquenes range.

The upper half of this gypseous formation is mainly formed of the same calcareous clay-shale rock, but without any gypsum, and varying extremely in nature: it passes from a soft, coarse, earthy, ferruginous state, including particles of quartz, into compact claystones with crystallised oxide of iron,--into porcellanic layers, alternating with seams of calcareous matter,--and into green porcelain-jasper, excessively hard, but easily fusible.Strata of this nature alternate with much black and brown siliceo-calcareous slate, remarkable from the wonderful number of huge embedded logs of silicified wood.This wood, according to Mr.R.Brown, is (judging from several specimens) all coniferous.Some of the layers of the black siliceous slate contained irregular angular fragments of imperfect pitchstone, which I believe, as in the Uspallata range, has originated in a metamorphic process.There was one bed of a marly tufaceous nature, and of little specific gravity.Veins of agate and calcareous spar are numerous.

The whole of this gypseous formation, especially the upper half, has been injected, metamorphosed, and locally contorted by numerous hillocks of intrusive porphyries crowded together in an extraordinary manner.These hillocks consist of purple claystone and of various other porphyries, and of much white feldspathic greenstone passing into andesite; this latter variety included in one case crystals of orthitic and albitic feldspar touching each other, and others of hornblende, chlorite, and epidote.The strata surrounding these intrusive hillocks at the mines of Los Hornos, are intersected by many veins of copper-pyrites, associated with much micaceous iron-ore, and by some of gold: in the neighbourhood of these veins the rocks are blackened and much altered.The gypsum near the intrusive masses is always opaque.One of these hillocks of porphyry was capped by some stratified porphyritic conglomerate, which must have been brought up from below, through the whole immense thickness of the overlying gypseous formation.The lower beds of the gypseous formation resemble the corresponding and probably contemporaneous strata of the main Cordillera;whilst the upper beds in several respects resemble those of the Uspallata chain, and possibly may be contemporaneous with them; for I have endeavoured to show that the Uspallata beds were accumulated subsequently to the gypseous or Neocomian formations of the Cordillera.

同类推荐
  • 入蜀记

    入蜀记

    本书为公版书,为不受著作权法限制的作家、艺术家及其它人士发布的作品,供广大读者阅读交流。汇聚授权电子版权。
  • 沈氏女科辑要

    沈氏女科辑要

    本书为公版书,为不受著作权法限制的作家、艺术家及其它人士发布的作品,供广大读者阅读交流。汇聚授权电子版权。
  • BLIX

    BLIX

    本书为公版书,为不受著作权法限制的作家、艺术家及其它人士发布的作品,供广大读者阅读交流。汇聚授权电子版权。
  • 御制水忏

    御制水忏

    本书为公版书,为不受著作权法限制的作家、艺术家及其它人士发布的作品,供广大读者阅读交流。汇聚授权电子版权。
  • 洞玄灵宝二十四生图经

    洞玄灵宝二十四生图经

    本书为公版书,为不受著作权法限制的作家、艺术家及其它人士发布的作品,供广大读者阅读交流。汇聚授权电子版权。
热门推荐
  • 云台夜话

    云台夜话

    一把剑,名为末日天使,两座城,生化人建城云台,不死者居于夜话,而人类,只能散落在荒野。废土之上,妖孽横行,是新人类的绽放,还是顾有的沉沦。
  • 名媛社交术:跻身社交名媛的10堂课

    名媛社交术:跻身社交名媛的10堂课

    女人只有拥有完美圆熟的社交形象、圆融通达的社交手法、淡定从容的社交心理、恰到好处的社交分寸,才能成为社交场合的焦点,享有坚定稳固的人际关系,并最终获得成功,踏入社交名媛的行列。
  • 网游之星球

    网游之星球

    当人生重来时,孙虹泽能否将家人守护起来?
  • 岁月有张凶手的脸

    岁月有张凶手的脸

    一次初中老同学聚会,引出四起汽车连环爆炸案;七名可能的犯罪嫌疑人,五个似是而非的真相;慢吞吞的女警携手颜值爆表的中学英语老师联合破案——他们是希望破解迷局,还是另有所图?一手遮天的高官、貌合神离的夫妇、游走爱欲边缘的职业二奶、濒临破产的小企业主、甚至于行走于世俗的僧人……每一个人都在说谎,每一个人都在试图掩饰他们所知的“真相”。十五天的推理追踪,倒计时48小时的最后通牒……当枪声在最后一秒响起——也许,人人都是凶手。当美德在某些时刻表现为软弱,而恶行却在沉默中彰显着力量时,是这个世界在崩坏,还是我们早已不是最初的自己?
  • 天生飘零

    天生飘零

    80后大学生丽江创业故事——献给冷漠的时代最后的一首爱情诗。他们是80后,身处一个荒芜和冷酷的年代。当别人都在追逐着欲望的时候,他们追逐着梦想。他们没房没车,却有着一整座天空之城和铺天盖地的光亮。三个年轻人,凭着满腔的热血和激情,满怀向往千里奔赴丽江创业,他们要如何在陌生之地落地生根,途中又会经历什么样的人情冷暖,当纯真的爱情遭遇现实的抵抗,他们又将如何抉择?无论曾经多么彷徨挣扎,每一个青春,都是值得骄傲的。也许你被囚禁于都市的牢笼无法呼吸,也许你已经动身远行。也许你终归会接受,也许你一直在叛逆。无论你处于什么样的境地,都别忘记,这个属于我们的时代,终归过去,而未来正在到来。献给所有的80后,献给我们这个荒芜而美好的年代。
  • 江山美人我都要

    江山美人我都要

    视美男如空气(没了不能活)的江色儿,因机缘巧合,恰逢紫微星现,来到了天圣国,一个女尊的世界。身为天圣的二皇女,她没有争权夺嫡的觉悟,成天流连男色,本着坚忍不拔的毅力,誓要网罗天下美人于怀中,却不知,树欲静而风不止,纵使她淡然,却依然逃不过大皇女的连环阴谋……流落东安为质,她尚不知危险一步步逼近,天真的以为,还可以过平静的猎艳生活,阴差阳错,得了东安玄王的心,却不料,幕后黑手悄然伸了出来。亲眼目睹一直守护她的护卫夜的死,她幡然醒悟,决心报仇……母皇被囚,她临危受命,当上了萧城城主,恰逢干旱,四两拨千斤,于云家交易,瓦解了大皇女的囤粮不放的阴谋。乌金来攻,无意间得到前辈的手札,有了炸药;乌金士兵身患天花,她不计前嫌带兵帮忙,那天人一般的丞相和她里应外合,妖娆邪恶的暗月教教主也来帮忙,乌金皇宫池里,锦鱼跃水,腹含黄绫曰:圣女转世。以一城之力,收服乌金国,创造了历史的神话。云岫山上,冰雪之姿的男子,以血为誓,命运和她紧紧相连,以飞蛾扑火,灭了蝗灾,梯田水灌,农业欣欣向荣。再回东安,惊知女皇竟然是男扮女装,还对她一片冰心,天降神仙清然吵着要嫁她,身负灵药,助东安皇帝金蝉脱壳,和她比翼双飞。母皇突然驾崩,伤心之余,贸然回京,得深明大义的尹风相助,斗智斗勇,谁与争锋,却不料,大皇女一心想的的遗诏竟然在……当上女皇,惊闻夜还活着,几相纠缠,终修成正果,众美齐聚,女皇娶妃,普天同庆……本文女尊一女N男+小白+小虐+小搞笑卷一多情质子,呵呵,纯小白卷二ms会比较大气一点亲亲们喜欢就收藏,投票,留言,^__*)嘻嘻…,你们的支持是某猪的动力!!《靠,我要带球跑》巧儿妹妹的《冷宫冷后》
  • 洪都侠客

    洪都侠客

    史记至正二十三年(公元1363年)元朝统治已将崩溃,天下纷乱 ,农民起义军峰欠连天。统一天下、各路豪杰志士又动干戈。来元璋传令徐达率军进驻南昌,改南昌为洪都,接看令自己的养子都督来朱文正、欠元帅赵德胜知参攻邓愈等将领驻审洪都。在江州(令九江),陈友谅改国号为汉,欠感疆域日益狭小,于是积极赶出兵向朱元璋收复失地,修速批巨型舰船、游载兵蒋、官吏,号称六十万欠军,倾国而出,从长江进入都阳湖,深入章江(令赣江),四月间,举围攻洪都城。藤王阁比武刀认仇家 眼见陈友谅军不日到达,洪都府中,人心惶恐,甚是纷乱。
  • 花都小兵王

    花都小兵王

    新书发布了!新书《我的游戏能捉鬼》,已经发布,快来阅读,记得投票票哦!他是战场的死神,千万战火,直取敌方上将首级。他是佣兵界的传奇,一个代号“火龙”的不死男人。书友群:307189029
  • 命运三国之龙套觅封侯

    命运三国之龙套觅封侯

    街亭之失,引发星落五丈原,假若街亭不失呢?
  • 浑身痒痒

    浑身痒痒

    进入腊月,老更也进入了临战状态,小儿子惠临腊月初九就要结婚了,想想,还有许多事等着他去做。昨天媒人捎过话来,说过红的时候,给女方家送的离娘肉要大一点,别只割了一小绺,猪尾巴似的,让人瞧不起。媒人还说,倒不是女孩的爹娘想多吃您家二斤猪肉,主要表示对女方家的尊重。老更说:那是自然的,我家虽不富裕,不过夹夹缩缩的事我还是不做。老更的话说得很有底气,事实上老更也真不是小气的人,大事小事老更也是办过几件的,比如养老送终娶媳盖房,在牛家铺子,真没给别人留下可以咀嚼长短的口舌。