Pub Date : 2020-07-10DOI: 10.12789/geocanj.2020.47.155
A. Kerr
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Pub Date : 2020-07-10DOI: 10.12789/geocanj.2020.47.159
A. Kerr
The spectacular angular unconformity at Siccar Point is the most famous site associated with James Hutton (1726–1797), but it was not his only place of insight. In 1785, three years before he discovered Siccar Point, Hutton examined outcrops in the still-remote valley of Glen Tilt, in the Scottish Highlands. He documented contact relationships between Precambrian metasedimentary rocks and Paleozoic granite bodies, although he had no knowledge of their true ages. Near to the hunting lodge where he and his colleague John Clerk of Eldin stayed, veins of granite clearly cut through relict bedding in the stratified rocks and disrupt their layering, breaking apart individual strata and leaving fragments (xenoliths) surrounded by granite. Hutton correctly deduced that the granite must originally have been in a ‘state of fusion’ and was forcefully injected into much older ‘schistus’. Such conclusions contravened prevailing ideas that granite bodies formed from aqueous solutions, and also refuted a wider philosophical view that granite and other crystalline rocks were the oldest and first-created parts of the Earth. Hutton’s key outcrops in Glen Tilt are easy to visit, although they do require a long (but easy) roundtrip hike of some 25 km. These are certainly not the most spectacular intrusion breccias that I have ever seen, but they are very instructive, and were very influential, because they sparked a long, and at times acrimonious, debate about the origins of igneous rocks and especially granite. This controversy had many strange twists and turns. These include the disappearance of Hutton’s original manuscript after his death, and its serendipitous rediscovery a century later, and the similar loss and rediscovery of exquisite drawings by John Clerk, almost two centuries after they were first penned. Among the lost drawings is an early example of detailed outcrop-scale mapping, which would become a key field-work technique. Hutton’s vision of granite as the product of hot, liquid material that moved upward in the Earth’s crust (plutonism) eventually prevailed over the idea that crystalline rocks formed from a primordial ocean that once enveloped the Earth (neptunism), but this victory did not come easily or quickly. In another strange twist of history, new evidence from the Cape of Good Hope in South Africa eventually acted to further the plutonist cause. Glen Tilt has changed very little since the time of Hutton, but the observations that were made here, and the long debate that followed, brought fundamental changes in our understanding of the Earth. Although Siccar Point should remain the first entry on the bucket list of any prospective geopilgrim to Scotland, the long and beautiful valley of the River Tilt should also be a priority. RÉSUMÉLa spectaculaire discordance angulaire de Siccar Point est le site le plus célèbre associé à James Hutton (1726–1797), mais ce n'était pas le seul lieu qui l’ait inspiré. En 1785, trois ans avant de découvrir Sic
西卡角壮观的角度不整合是与詹姆斯·赫顿（1726-1797）有关的最著名的地点，但这并不是他唯一的洞察力所在。1785年，在他发现Siccar Point的三年前，Hutton检查了苏格兰高地仍然偏远的Glen Tilt山谷的露头。他记录了前寒武纪变质沉积岩和古生代花岗岩体之间的接触关系，尽管他不知道它们的真实年龄。在他和同事埃尔丁的约翰·克莱克（John Clerk of Eldin）居住的狩猎小屋附近，花岗岩的矿脉清楚地穿过层状岩石中的残余层理，破坏了它们的分层，撕裂了各个地层，留下了被花岗岩包围的碎片（捕虏体）。Hutton正确地推断出，花岗岩最初一定处于“融合状态”，并被有力地注入了更古老的“片岩”中。这些结论违背了花岗岩体由水溶液形成的主流观点，也驳斥了更广泛的哲学观点，即花岗岩和其他结晶岩石是地球上最古老和最早形成的部分。Hutton在Glen Tilt的主要露头很容易参观，尽管它们确实需要大约25公里的长时间（但很容易）往返徒步旅行。这些当然不是我见过的最壮观的侵入角砾岩，但它们非常有指导意义，也非常有影响力，因为它们引发了关于火成岩，尤其是花岗岩起源的长期争论，有时甚至激烈。这场争论有许多奇怪的曲折。其中包括赫顿去世后原稿的消失，以及一个世纪后偶然的重新发现，以及约翰·克莱克在精美画作首次创作近两个世纪后的类似丢失和重新发现。在丢失的图纸中，有一个详细的露头比例测绘的早期例子，这将成为一项关键的野外工作技术。Hutton认为花岗岩是地壳中向上移动的热液体物质的产物（深成主义），最终战胜了晶体岩石是由曾经包围地球的原始海洋形成的观点（海王星主义），但这一胜利来之不易。在另一个奇怪的历史转折中，来自南非好望角的新证据最终推动了政治经济学事业。自Hutton时代以来，Glen Tilt几乎没有变化，但在这里进行的观测以及随后的长期辩论，使我们对地球的理解发生了根本性的变化。尽管Siccar Point应该仍然是苏格兰潜在地质专家名单上的第一个项目，但倾斜河漫长而美丽的山谷也应该是优先事项。Siccar Point的RÉSUMÉLa壮观的不和谐角度是詹姆斯·赫顿（1726-1797）的一个地点，这是一个充满灵感的地方。1785年，在Siccar Point的三驾马车上，Hutton对高地的Glen Tilt的英勇事迹进行了考察。这是一份与柬埔寨人民和Paléozoïque花岗岩军团之间的联系文件，这是一个值得纪念的时刻。Eldin ont séjourné的John Clerker和Chlègue之子的pavillon de chasse oúlui先生，花岗岩脉是分层和扰动叠加的宗教序列的组成部分，是花岗岩内部碎片（xénolithes）的个人策略和来源。Hutton纠正了“融合状态”的起源，并为“分裂”和古代注入了力量。我们得出的结论是，花岗岩军团的主导者是解决方案的一部分，也是未来哲学愿景的一部分。HuttonàGlen Tilt的主要工作人员很容易访问，因为他们需要在25公里外的环境中进行长期的访问。这是一个肯定的事实，因为它是一种入侵，加上我的眼睛，我的眼睛是一种指导，而不是欧盟的影响，汽车是一种长时间的撞击，是一种激烈的争论，是关于岩石的起源，尤其是花岗岩的起源。这是对欧盟重新组建的一次反对。Ceux ci包括Hutton的原始手稿的差异，以及一个偶然的加上延迟的红色，以及John Clerk的再婚设计的相似性和红色。
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Pub Date : 2020-07-10DOI: 10.12789/geocanj.2020.47.157
M. Wit, B. Linol, V. Nengovhela
The Kango (Cango) region flanks the northern margins of the Klein Karoo and the Cape Mountains across the Western Cape Province of South Africa. It preserves a condensed Proterozoic–Paleozoic stratigraphy exposed via a Mesozoic–Cenozoic morphology with a present Alpine-like topography. Its rocks and landscapes have been repeatedly mapped and documented for the past 150 years. Over the last 25 years, we remapped and dated a central-eastern section of this region. The subvertically bedded and cleaved rocks reveal an 8–10 km thick stratigraphy covering more than 700 million years between ca. 1200 and 500 Ma with several unconformities and disconformities. At ca. 252 Ma, during the Cape orogeny, this Kango Complex was deformed along thrusts and sub-isoclinal folds producing steeply dipping phyllites and slates. It was uplifted by 3–5 km during the Kalahari epeirogeny between 140 and 60 Ma while eroding at ca. 100–200 m/m.y. (120–80 Ma). During the Cenozoic, the rate of uplift decreased by an order of magnitude and today is ca. 0.4–0.7 m/m.y. across steep slopes and canyons in contrast to the Himalayas where erosion rates are about hundred times faster. A recent publication about this central-eastern section of the Kango region disputes the existence of regional isoclinal folds and suggests that deposition of the oldest sedimentary successions, including carbonate rocks of the Cango Caves (limestone-marble with enigmatic microfossils) was simple, continuous and restricted to between ca. 700 and 500 Ma, decreasing earlier estimates of the stratigraphic age range by 60–80%. Similarly, recent interpretations of the complex landscapes link the northern contact between the Kango and Table Mountain rock sequences to Quaternary faults. We present a new geological database, mapped between 1:500 and 1:10,000 scales, and twelve stratigraphic sections with younging directions linked to structural and isotopic data that support repetitions along regional isoclinal folds and thrust zones of the Kango sequences during the Permo–Triassic Cape orogeny, and geomorphic data that link the origin of its landscapes to weathering and erosion during the Cretaceous–Cenozoic Kalahari epeirogeny. During its evolution, the Kango Basin directly flanked both Grenvillian and Pan-African Mountain systems. But, at an average sedimentation rate of ca. 1 mm/70 years (0.014 mm/year) and with present low erosion rates (0.005 mm/year), there is likely more time missing than preserved of the tectono-erosion across these different regions of Rodinia and Gondwana before Africa emerged. To further evaluate the geodynamic significance of these time gaps requires more field mapping linked to new transdisciplinary geosciences. RÉSUMÉLa région du Kango (Cango) flanque les marges nord du petit Karoo et des montagnes du Cap dans la province du Western Cape en Afrique du Sud. Elle préserve une stratigraphie condensée protérozoïque–paléozoïque exposée via une morphologie mésozoïque–cénozoïque avec u
康戈(Cango)地区位于克莱因卡鲁和开普山脉的北部边缘，横跨南非西开普省。它保留了一个浓缩的元古代-古生代地层，通过中新生代的形态暴露出来，具有现在的高山状地形。在过去的150年里，它的岩石和景观被反复绘制和记录。在过去的25年里，我们重新绘制了该地区中东部的地图，并确定了年代。亚垂直层状和劈裂岩石显示出8-10公里厚的地层，覆盖约1200 - 500 Ma之间的7亿多年，并有一些不整合和不整合。约252 Ma，在开普造山运动期间，该坎戈杂岩沿逆冲和次等斜褶皱变形，形成了陡倾千层岩和板岩。在140 ~ 60 Ma的喀拉哈里造山运动期间，抬升了3 ~ 5 km，侵蚀速度约为100 ~ 200 m/m.y。(120 - 80 Ma)。在新生代，抬升速率降低了一个数量级，今天的抬升速率约为0.4-0.7 m/m.y.。穿越陡峭的山坡和峡谷，而喜马拉雅山的侵蚀速度要快上百倍。最近一份关于Kango地区中东部地区的出版物对区域等斜褶皱的存在提出了质疑，并认为最古老的沉积序列，包括Cango洞穴(石灰石-大理石和神秘的微化石)的碳酸盐岩的沉积是简单的，连续的，并且限制在大约700到500 Ma之间，将早期对地层年龄范围的估计降低了60-80%。同样，最近对复杂地貌的解释将康戈和桌山岩石层序之间的北部接触与第四纪断裂联系起来。我们提出了一个新的地质数据库，绘制了1:500到1:10 000的比例尺，12个地层剖面的年轻方向与构造和同位素数据相关联，这些数据支持二叠纪-三叠纪Cape造山运动期间Kango序列沿区域等斜褶皱和冲断带的重复，以及将其景观起源与白垩纪-新生代Kalahari造山运动期间的风化和侵蚀联系起来的地貌数据。在其演化过程中，Kango盆地直接位于格伦维利安山脉和泛非山脉的两侧。但是，在平均沉积速率约为1毫米/70年(0.014毫米/年)和目前较低的侵蚀速率(0.005毫米/年)的情况下，在非洲出现之前，罗迪尼亚和冈瓦纳这些不同地区的构造侵蚀可能比保存的时间更少。为了进一步评估这些时间间隙的地球动力学意义，需要更多与新的跨学科地球科学相联系的野外测绘。RÉSUMÉLa康戈共和国(康戈)附属于小卡鲁北部地区和丹斯角山区、西开普省和南非洲。通过一个morphologie Elle保存一个stratigraphie condensee proterozoique-paleozoique exposee mesozoique-cenozoique用一个topographie actuelle de alpin类型。这些数据包括:电子数据、电子数据、电子数据、电子数据、电子数据、电子数据、电子数据、电子数据、电子数据、电子数据和电子数据。Au course des 25 derniires annacei, nous avons re- cartographihi<s:1>和dataest section du centrest de ceetacei。从地层上看，有8 × 10 km和7 × 10 km和7 × 10 km，分别是不符合条件的、不符合条件的和不符合条件的。À 252 Ma, au ' orogenses de Cap, ce de Kango复合物' s est danci.9cha.com, le long de chevauchements and plisisoclinaux prochistes chiistes pendage。1 .在Kalahari中心140至60英里处的3公里处，有1个<s:1> <s:1> 5公里处的<s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> - 200米/小时。(120 - 80 Ma)。Pendant le Cénozoïque, le taux de souldevement和miniuvel 'un order de magnificent等将在每年0,4至0,7 m/m之间进行测试。<s:2>穿越山脉，穿越峡谷，穿越峡谷，穿越喜马拉雅山脉où，穿越高山，穿越高山，穿越环境，穿越高山，穿越急流。一份出版物《<s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1>)》，其中包括<s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1> <s:1>(或)<s:1> <s:1> <s:1>(或)<s:1> <s:1>(或)有限的(或)简单的、连续的、有限的)<s:1>(700至500 Ma)的环境，以及60-80%的<s:1> <s:1>地层)。电子邮箱même，电子邮箱，电子邮箱，电子邮箱，电子邮箱，电子邮箱，电子邮箱，电子邮箱。 我们提出一个新的地质数据库,绘制地图比例尺1:50至1:10,000、十二和地层剖面结构叠加与管理层的相关数据和信息吻合的同位素与沿线区域的褶皱isoclinaux彩排期间Kango的序列重叠区l’orogenèse permo—triassique开普敦以及将其地貌起源与卡拉哈里火山成因至白垩纪至新生代期间的蚀变和侵蚀联系起来的地貌数据。在其发展过程中，坎戈盆地两侧是格伦维尔山脉和泛非山脉。但是,平均沉降率约为1 / 70岁(0.014毫米/年),并与现有的侵蚀率低(0.005 mm / yr),他可能缺乏更大地和侵蚀,这些记录Rodinia不同区域和Gondwana非洲崛起之前,这是目前保存完好。为了评估这些缺失时间间隔的地球动力学意义，需要更多的地面测绘与新的跨学科地球科学相结合。
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Pub Date : 2020-07-10DOI: 10.12789/geocanj.2020.47.160
E. Koster
Increasingly, deliberations to potentially add the Anthropocene to the Geological Time Scale in recognition of humanity’s environmental impacts and stratigraphic record are attracting interest from non-geological disciplines and the news media. The 35 member Anthropocene Working Group, a constituent body of the International Commission on Stratigraphy, recently concluded that the worldwide fallout of radionuclides from atomic bomb testing in the mid-20th century best defines the base of the Anthropocene. With a search for the optimal ‘golden spike’ locality in progress as a key step toward any ratification by the International Union of Geological Sciences, there are widely held views outside of geological circles that the Anthropocene is already designated as an epoch. Regardless of its eventual formal or informal standing, this article opines that the term Anthropocene has become valuable shorthand for recognizing humanity as the dominant species which, in a geological nanosecond, has extensively detached itself from the Earth System, endangering the future of both. Accordingly, this article urges the entire geological profession to engage with the work of the Anthropocene Working Group and, as the originator of the term, to coalesce its activities with those of other disciplines concerned with environmental health and linked human health challenges. RÉSUMÉDe plus en plus, les délibérations visant à éventuellement ajouter l'Anthropocène à l'échelle du temps géologique en reconnaissance des impacts environnementaux de l'humanité et des données stratigraphiques suscitent l'intérêt des disciplines non géologiques et des médias. Les 35 membres du Groupe de travail sur l'Anthropocène, un organe constitutif de la Commission internationale de stratigraphie, ont récemment conclu que les retombées mondiales des radionucléides résultant des essais de bombes atomiques au milieu du XXe siècle définissent le mieux la base de l'Anthropocène. Avec la recherche de la localité de référence optimale du « clou d'or » en cours comme étape clé vers toute ratification par l'Union internationale des sciences géologiques, il existe des opinions largement partagées en dehors des cercles géologiques selon lesquelles l'Anthropocène est déjà désigné comme une époque. Indépendamment de sa position finale formelle ou informelle, cet article estime que le terme Anthropocène est devenu un raccourci précieux pour reconnaître l'humanité comme l'espèce dominante qui, dans une nanoseconde géologique, s'est largement dissocié du système terrestre, mettant en danger l'avenir des deux. Par conséquent, cet article exhorte l'ensemble de la profession géologique à s'engager dans les travaux du Groupe de travail sur l'Anthropocène et, en tant que créateur du terme, à fusionner ses activités avec celles d'autres disciplines concernées par la santé environnementale et les défis liés à la santé humaine.
考虑到人类对环境的影响和地层记录，有可能将人类世添加到地质时间尺度中，这引起了非地质学科和新闻媒体的兴趣。人类世工作组由35名成员组成，是国际地层学委员会的一个组成机构，最近得出结论，20世纪中期原子弹试验产生的放射性核素在世界范围内的沉降物最好地定义了人类世的基础。寻找最佳的“金钉”位置是获得国际地质科学联合会(International Union of Geological Sciences)认可的关键一步，在此过程中，地质圈之外有广泛的观点认为，人类世已经被指定为一个时代。无论其最终的正式或非正式地位如何，这篇文章认为，“人类世”一词已经成为一种有价值的简写，它承认人类是在地质纳秒内广泛脱离地球系统的主导物种，危及两者的未来。因此，本文敦促整个地质专业参与人类世工作组的工作，并作为该术语的发起者，将其活动与与环境健康和相关人类健康挑战有关的其他学科的活动结合起来。RÉSUMÉDe + en + en +，将所有的人都纳入到人类系统的范围内，将所有的人都纳入到人类系统的范围内，将所有的人都纳入到人类系统的范围内，将所有的人都纳入到人类的范围内。人类工作小组的35个成员，国际地层学委员会的组织组成，以及人类工作小组的35个成员，人类工作小组的35个成员，人类工作小组的35个成员，人类工作小组的35个成员，人类工作小组的35个成员，人类工作小组的35个成员。如果在国际科学联盟的批准中，将有许多意见存在，例如，在国际科学联盟的批准中，将有许多意见存在，例如，在国际科学联盟的批准中，将有许多意见存在，例如，在国际科学联盟的批准中，将有许多意见存在，例如，将有许多意见存在，例如，将有许多意见存在，例如，将有许多意见存在，例如，将有许多意见存在，例如，将有许多意见存在，例如，将有许多意见存在，例如，将有许多意见存在，例如，将有许多意见存在，例如，将有许多意见存在，例如，将有许多意见存在，例如，将有许多意见存在。1 . 人道主义系统系统的最大分离，1纳秒人道主义系统系统的最大分离，1纳秒人道主义系统系统的最大分离，1纳秒人道主义系统系统的最大分离，1纳秒人道主义系统系统的最大分离，1纳秒人道主义系统系统的最大分离。与此同时，该条款还敦促所有职业的薪金薪金与人类职业的薪金薪金有关，所有职业的薪金薪金与人类职业的薪金薪金有关，所有职业的薪金薪金与人类职业的薪金薪金有关，所有职业的薪金薪金与人类职业的薪金薪金有关，所有职业的薪金薪金与人类职业的薪金薪金有关。
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Pub Date : 2020-07-10DOI: 10.12789/geocanj.2020.47.158
V. Oliveros, P. Moreno-Yaeger, Laura Flores
Andean-type magmatism and the term ‘andesite’ are often used as the norm for the results of subduction of oceanic lithosphere under a continent, and the typical rock formed. Although the Andes chain occupies the whole western margin of South America, the most comprehensively studied rocks occur in the present-day Chilean territory and are the focus of this paper. Andean magmatism in this region developed from the Rhaetian-Hettangian boundary (ca. 200 Ma) to the present and represents the activity of a long-lived continental magmatic arc. This paper discusses Pre-Pleistocene volcanic, plutonic, and volcano-sedimentary rocks related to the arc that cover most of the continental mass of Chile (between the Pacific coast and the High Andes) between the latitudes of 18° and 50°S. They comprise most of the range of sub-alkaline igneous rocks, from gabbro to monzogranite and from basalt to rhyolite, but are dominated by the tonalite-granodiorite and andesite example members. Variations in the petrographic characteristics, major and trace element composition and isotopic signature of the igneous rocks can be correlated to changes in the physical parameters of the subduction zone, such as dip angle of the subducting slab, convergence rate and angle of convergence. Early Andean magmatic products (Jurassic to Early Cretaceous) are found along the Coastal Cordillera in the westernmost part of the Andes. The rock record of the subsequent stages (Late Cretaceous, Paleocene–Early Eocene, Middle Eocene–Oligocene, Miocene) is progressively shifted to the east, reflecting migration of the magmatic front towards the continent. Tectonic segmentation of the convergent margin, as attested by the magmatic record, may have occurred throughout the Andean life span but it is particularly evident from the Eocene onwards, where the evolution of the northern part of the Chilean Andes (north of 27°S latitude) is very different to that of the southern segment (south of 27°S latitude). RÉSUMÉLe magmatisme de type andin et le terme « andésite » sont souvent les appellations utilisées pour décrire les résultats de la subduction de la lithosphère océanique sous un continent, et la roche typique formée. Bien que la chaîne des Andes occupe toute la marge ouest de l'Amérique du Sud, les roches les plus étudiées se trouvent dans le territoire chilien actuel et sont l'objet de cet article. Le magmatisme andin dans cette région s'est développé depuis la limite rhéto-hettangienne (environ 200 Ma) jusqu'à aujourd'hui et représente l'activité d'un arc magmatique continental persistant. Cet article a pour sujet les roches volcaniques, plutoniques et volcano-sédimentaires du pré-Pléistocène liées à l'arc qui couvrent la majeure partie de la masse continentale du Chili (entre la côte du Pacifique et les Hautes Andes) entre les latitudes de 18° et 50°S. Elles comprennent la majeure partie de la gamme de roches ignées sous-alcalines, du gabbro à la monzogranite et du basalte à la rhyolite, mais
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Pub Date : 2019-12-18DOI: 10.12789/geocanj.2019.46.153
K. Karlstrom, L. Crossey
The year 2019 is the 150th anniversary of John Wesley Powell’s epic exploration of the Colorado River through Grand Canyon and the 100th anniversary of the establishment of Grand Canyon National Park. This is an excellent moment to look back 150 years to think about where we have come from as a science and society, and look forward 100 years towards the accelerated change we expect in the future. For historians, archaeologists, geologists and astronomers, of course, this century-long time scale is short compared to other perspectives. They might choose also to celebrate the 479th anniversary of the first sighting of Grand Canyon by Europeans in 1540, the 1000th anniversary of Ancestral Puebloan farmers in Grand Canyon, the 12,000th anniversary of the arrival of humans migrating south from the Bering Land Bridge, the 5 millionth anniversary of the integration of the Colorado River through Grand Canyon to the Gulf of California, the 4.6 billionth anniversary of the formation of Earth, or the 13.75 billionth anniversary of the Big Bang and the formation of our Universe. Geology is all about time, and knowing some geology helps with the difficult endeavour of placing human timeframes into perspectives of deep time. This guide is for geology students of all levels and types visiting the South Rim of Grand Canyon. It is designed as a 3-day field trip and introduction to the rocks and landscapes. The term ‘students’ in our view also includes visitors who want to know about the basics of Grand Canyon geology while taking scenic hikes to see the geology first-hand. It is organized as if you enter the Park at its East entrance, near Cameron, and exit the Park at the South entrance, towards Flagstaff, but the three activities can be done in any order. As an introduction, we present a brief summary of the history of geologic maps and stratigraphic columns, and the geologists who made them. The maps and depictions of Grand Canyon geology over the past 160 years record a visual progression of how geoscience knowledge in general has developed and matured. The first sixty years, before the Park was founded, may have been the greatest in terms of the rapid growth that merged geology, art and public outreach. The second fifty years (to about 1969) saw important advances in stratigraphy and paleontology and solid efforts by the Park to apply and interpret Grand Canyon geology for the public. The most recent 50 years have seen major advances in regional geological mapping, dating of rocks, plate tectonics, and improved geoscience interpretation. The next 100 years will hopefully see additional innovative efforts to use the iconic field laboratory of Grand Canyon rocks and landscapes to resolve global geoscience debates, inform resource sustainability imperatives and contribute to science literacy for an international public. The three activities described are as follows: Activity 1 (an hour or two) is an overview from Lipan Point. This is a vehicle pull-out on the
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Pub Date : 2019-12-18DOI: 10.12789/geocanj.2019.46.152
Dène Tarkyth
It was my pleasure to serve as the president of this organization through 2018 and part of 2019, and such an experience cannot help but remind me of the effort that comes from GAC staff and our many volunteers, but it also brought home the challenges that all of us face in organizing our time and activities in this so-called Information Age. We live in a world where both space and time are increasingly compressed, and all of us at times struggle to manage the demands of our work and our lives beyond the office walls. So I will start this address by asking you all to imagine that you had one extra day a week given to you some time that you could spend on fun science and investigating exciting questions, or just catching up on work and life. Would we not all welcome such a gift? But then look back over the last few weeks, months or even years and think about how much time you spent searching for information, skimming papers to finding sample locations, compiling and cleaning up data, georeferencing maps....just some of the many basic things that need to get done before you can get to the fun part of your job as a geoscientist. There are estimates that geologists now spend 80% of their time searching for, formatting and organizing information and data, and I do not find these hard to believe. A recent article highlighted the approach taken by Cameco, one of Canada’s leading mining companies, to change how they manage data in order to save 20% of their geologists’ time – one day a week – so that they would not have to spend countless hours looking for data and could do geology instead (Heffernan 2015). There are many efforts to amalgamate and process data in ways that make this process easier and more amenable to automation. A young student geologist at Princeton University, Julia Wilcots, undertook a summer project with a senior researcher at University of Wisconsin to examine the distribution of stromatolites through geological time by searching descriptive literature. Anyone who has worked in the Precambrian, or indeed in sedimentary rocks of any Eon or Era, can well imagine the immensity of that search. However, through the use of computer search techniques and the ‘Geodeepdive’ database, she was quickly able to identify over 10,000 papers that mentioned stromatolites (in the text, but not necessarily in the title) and extract the associated rock unit names from 10% of them. Then, by linking these results to the ‘Macrostat’ database, she was then able to come up with an estimate of the percentage of shallow marine rocks that contain stromatolites within different geological time periods. A more senior researcher at the University involved with the project estimated that doing this same search would have taken him sixteen months of tedium. The overall conclusions of the study – that the distribution of stromatolites is most closely linked to the abundance of dolomitic carbonate rocks (Peters et al. 2017) – are important, but the methodology demons
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Pub Date : 2019-10-31DOI: 10.12789/geocanj.2019.46.151
T. Rivers
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Pub Date : 2019-10-31DOI: 10.12789/geocanj.2019.46.150
S. Mccutcheon, J. Walker
The Bathurst Mining Camp of northern New Brunswick is approximately 3800 km2 in area, encompassed by a circle of radius 35 km. It is known worldwide for its volcanogenic massive sulphide deposits, especially for the Brunswick No. 12 Mine, which was in production from 1964 to 2013. The camp was born in October of 1952, with the discovery of the Brunswick No. 6 deposit, and this sparked a staking rush with more hectares claimed in the province than at any time since. In 1952, little was known about the geology of the Bathurst Mining Camp or the depositional settings of its mineral deposits, because access was poor and the area was largely forest covered. We have learned a lot since that time. The camp was glaciated during the last ice age and various ice-flow directions are reflected on the physiographic map of the area. Despite abundant glacial deposits, we now know that the camp comprises several groups of Ordovician predominantly volcanic rocks, belonging to the Dunnage Zone, which overlie older sedimentary rocks belonging to the Gander Zone. The volcanic rocks formed during rifting of a submarine volcanic arc on the continental margin of Ganderia, ultimately leading to the formation of a Sea of Japan-style basin that is referred to as the Tetagouche-Exploits back-arc basin. The massive sulphide deposits are mostly associated with early-stage, felsic volcanic rocks and formed during the Middle Ordovician upon or near the sea floor by precipitation from metalliferous fluids escaping from submarine hot springs. The history of mineral exploration in the Bathurst Mining Camp can be divided into six periods: a) pre-1952, b) 1952-1958, c) 1959-1973, d) 1974-1988, and e) 1989-2000, over which time 45 massive sulphide deposits were discovered. Prior to 1952, only one deposit was known, but the efforts of three men, Patrick (Paddy) W. Meahan, Dr. William J. Wright, and Dr. Graham S. MacKenzie, focused attention on the mineral potential of northern New Brunswick, which led to the discovery of the Brunswick No. 6 deposit in October 1952. In the 1950s, 29 deposits were discovered, largely resulting from the application of airborne surveys, followed by ground geophysical methods. From 1959 to 1973, six deposits were discovered, mostly satellite bodies to known deposits. From 1974 to 1988, five deposits were found, largely because of the application of new low-cost analytical and geophysical techniques. From 1989 to 2000, four more deposits were discovered; three were deep drilling targets but one was at surface. RÉSUMÉLe camp minier de Bathurst, dans le nord du Nouveau-Brunswick, s’étend sur environ 3 800 km2 à l’intérieur d’un cercle de 35 km de rayon. Il est connu dans le monde entier pour ses gisements de sulfures massifs volcanogènes, en particulier pour la mine Brunswick n° 12, exploitée de 1964 à 2013. Le camp est né en octobre 1952 avec la découverte du gisement Brunswick n° 6 et a suscité une ruée au jalonnement sans précédent avec le plus d’hec
新不伦瑞克北部的巴瑟斯特采矿营地面积约为3800平方公里，周围环绕着一个半径为35公里的圆圈。它以其火山块状硫化物矿床而闻名于世，特别是1964年至2013年生产的Brunswick No. 12矿。该营地诞生于1952年10月，当时发现了不伦瑞克6号矿床，这引发了一股圈地热潮，该省声称拥有的土地面积比以往任何时候都多。1952年，人们对巴瑟斯特采矿营地的地质情况或其矿藏的沉积环境知之甚少，因为交通不便，而且该地区大部分被森林覆盖。从那时起，我们学到了很多。该营地在最后一个冰河时期被冰川覆盖，各种冰流方向反映在该地区的地理地图上。尽管有大量的冰川沉积，但我们现在知道该营地由几组奥陶系火山岩组成，这些火山岩主要属于垫内格带，它们覆盖在属于甘德带的更古老的沉积岩上。这些火山岩形成于Ganderia大陆边缘海底火山弧的裂谷过程中，最终形成日本海式盆地，称为Tetagouche-Exploits弧后盆地。块状硫化物矿床主要与早期长英质火山岩有关，形成于中奥陶世，由海底温泉中逸出的含金属流体沉淀而成。巴瑟斯特矿营的矿产勘探历史可分为6个时期:a) 1952年以前，b) 1952-1958年，c) 1959-1973年，d) 1974-1988年，e) 1989-2000年，在此期间共发现块状硫化物矿床45个。在1952年之前，只有一个矿床是已知的，但是Patrick (Paddy) W. Meahan博士、William J. Wright博士和Graham S. MacKenzie博士三个人的努力将注意力集中在新不伦瑞克北部的矿产潜力上，这导致了1952年10月发现了不伦瑞克6号矿床。在20世纪50年代，发现了29个矿床，主要是由于应用了航空测量，然后是地面地球物理方法。从1959年到1973年，发现了6个矿床，大多数是已知矿床的卫星体。从1974年到1988年，发现了5个矿床，主要是因为应用了新的低成本分析和地球物理技术。从1989年到2000年，又发现了四个矿床;三个是深层钻探目标，但一个在地面。RÉSUMÉLe新不伦瑞克省北部的巴瑟斯特长官，在3 800平方公里的范围内，在3 800平方公里的范围内，在35公里的范围内，在3 800平方公里的范围内，在3 800平方公里的范围内。在1964年至2013年期间开采的不伦瑞克矿，特别是在2013年开采的不伦瑞克矿。用la decouverte营地est ne en octobre 1952 du坐标偏角不伦瑞克n 6°等suscite一ruee盟jalonnement sans先例用+ d 'hectares revendiques瞿在省现在。En 1952年savait一些东西关于la学界du阵营如矿坑的德巴瑟斯特欧苏尔德莱斯条件沉积de ses坐标偏角mineraux,车l 'acces是非常接近于等拉区恩格兰德一部分recouverte de foret。“我的美丽，我的美丽，我的美丽，我的美丽。”在不同的方向上，在不同的方向上，在不同的方向上，在不同的方向上，在不同的方向上，在不同的方向上，在不同的方向上，在不同的方向上，在不同的方向上，在不同的方向上，在不同的方向上。Malgre des仓库glaciaires abondants,常识肥皂comprend几个营的小组号现在罗氏ordoviciennes优势volcanique, appartenant拉区衬垫,,recouvrent de + vieilles罗氏sedimentaires de la区闲逛。莱斯洛什火山群被命名为sous-marin - sur - la marge de Ganderia大陆上的火山群，这是关于它的形成的最后定论d 'un盆地类型的日本，又称盆地d ' arri<s:1> -arc de tetagouche -开发。Les坐标偏角de硫渣土是principalement过渡群系辅助罗氏volcaniques felsiques德施塔德precoce et se是形式分为de l 'Ordovicien平均苏尔或者接近du木板oceanique par la降水de流体metalliferes年代'echappant德源一边咕哝sous-marines。1 .关于勘探的历史:1)在1952年、b) 1952年至1958年、c) 1959年至1973年、d) 1974年至1988年和e) 1989年至2000年，分别对6种不同的<s:2> <s:2>或其他类型的<s:2>或其他类型的<s:2>或其他类型的<s:2>或其他类型的<s:2>或其他类型的<s:2>或其他类型的<s:2>或其他类型的<s:2>或其他类型的<s:2>或其他类型的<s:2>或其他类型的<s:2>进行了分类。1952年10月6日，新不伦瑞克北部潜在部长帕特里克(帕迪)W.米汉、威廉J.赖特和格雷厄姆S.麦肯齐，以及新不伦瑞克北部潜在部长的注意力，在1952年10月6日，新不伦瑞克北部潜在部长的注意力集中在了新不伦瑞克北部。 在20世纪50年代，发现了29个矿床，主要是利用航空调查和地面地球物理活动的结果。从1959年到1973年，发现了6个矿床。这些主要是已知矿床的卫星地层。从1974年到1988年，发现了5个矿床，主要是通过使用新的低成本分析和地球物理技术。从1989年到2000年，又发现了4个矿床。其中三个是深井目标，但一个在水面上。
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