Growth of Cratons and their Post-Stabilization Histories

2004 ◽  
Author(s):  
John J. W. Rogers ◽  
M. Santosh
Keyword(s):  
Continental Crust ◽  
Evolutionary Process ◽  
Major Elements ◽  
Tectonic Activity ◽  
Crustal Recycling ◽  
The Earth ◽  
History Of ◽  
Superior Craton ◽  
The Relationship ◽  
Comparative Stability

As we have seen in chapter 3, continental crust evolved from regions of the mantle that contained higher concentrations of LIL elements than regions that underlie typical ocean basins. The most complete record of this evolutionary process is in cratons, which passed through periods of rapid crust production to times of comparative stability over intervals of several hundred million years. After the cratons became stable enough to accumulate sequences of undeformed platform sediments, they moved about the earth without being subjected to further compressive tectonic activity. Because many of the cratons are also partly covered by sediments that are unmetamorphosed or only slightly metamorphosed, they appear to have undergone very little erosion since the sediments were deposited. Thus, a craton may be considered as a large block of continental crust that has been permanently removed from the crustal recycling process. This chapter starts with a discussion of the history of cratons as interpreted from studies of the upper part of the crust. We describe the Superior craton of the Canadian shield and the Western Dharwar craton of southern India within the chapter and use appendix E for brief summaries of other typical cratons. These cratons and numerous others elsewhere developed at different times during earth history, and we look for similarities and differences that may have been caused by progressive cooling of the earth (chapter 2). This section concludes with a summary of the general evolution of cratons and the meaning of the terms “Archean” and “Proterozoic.” The following section is an investigation of processes that occurred following stabilization, all of which take place in the presence of fluids that permeate the crust. We include a summary of these fluids and their effects on anorogenic magmatism and separation of the lower and upper crust. The final section discusses the relationship between cratons and their underlying subcontinental lithospheric mantle (SCLM). Continual metasomatism and metamorphism of the SCLM after cratons develop above it apparently has not destroyed the relationship between the ages of the cratons and the concentrations of major elements in the SCLM. This provides us with an opportunity to determine whether cratons evolved from the mantle beneath them or by depletion of much larger volumes of mantle. The discussions in this chapter are based partly on information summarized in appendices B (heat flow) and D (isotopes).

scholarly journals Memahami Sensionalisme dalam Berita Televisi: Perspektif Evolusi Biologi

2020 ◽  
Vol 16 (2) ◽  
Author(s):  
Gentur Agustinus Naru
Keyword(s):  
Human Brain ◽  
Evolutionary Biology ◽  
Evolutionary Process ◽  
Time Difference ◽  
Evolutionary Perspective ◽  
History Of ◽  
The Relationship

Although there have been many studies regarding sensationalism on television, there have not been enough studies to explain why sensational news always attracts viewers' attention regardless of space or time difference. Encouraged by this background, this research tries to answer the question, "What makes sensational news interesting to television viewers?" Inspired by a biological evolutionary perspective, this article formulates a hypothesis that reads, "Sensationalism can draw the attention of the audience because sensational news arouses the most basic instincts of humans, namely the mode of survival (Gurven, 2017)". In this view, the model has become inherent in humans as a result of the evolutionary process. In other words, this hypothesis also believes that audience interest in sensational news is universal rather than contextual.   This article explores a variety of literature in biology, psychology, and communication to try to answer that hypothesis. In order to that, this article is divided into three main sections. We will first explore the history of sensational journalism on television to show the historicity of sensational topics and techniques on television. Second, we will demonstrate the philosophical roots of an evolutionary biology view that explains the relationship between information stimuli and the workings of the human brain and the basic instincts we have carried since evolution thousands of years ago. Finally, we will show studies that prove empirically how news patterns (both sensational topics and production formats) impact viewing interest.

scholarly journals Seeing the History of the Earth in the Cliffs at Møn: The Interaction between Landscape Painting and Geology in Denmark in the First Half of the 19th Century

Romantik ◽  
2013 ◽  
Vol 2 (1) ◽  
pp. 77 ◽  
Author(s):  
Gry Hedin
Keyword(s):  
Nineteenth Century ◽  
19Th Century ◽  
Landscape Painting ◽  
The Earth ◽  
Man And Nature ◽  
History Of ◽  
The 19Th Century ◽  
The Relationship ◽  
Scientific Advances ◽  
The Way

During the first part of the nineteenth century, geologists developed a history of the earth so different from that accepted in previous centuries that it encouraged a rethinking of the relationship between man and nature. In this article I will argue that painters followed these changes closely and that some of them let the narratives and images of geology inform the way they depicted nature. In arguing my point, I will focus on images and descriptions of the chalk cliffs on the Danish island of Møn by both geologists and painters. I will follow the scientific advances in geology by referring to the texts and images of Søren Abildgaard, Henrich Steffens, Johan Georg Forchhammer, and Christopher Puggaard, and discuss how their changing theories correspond with paintings of the cliffs by four artists: Christopher Wilhelm Eckersberg, Frederik Sødring, Louis Gurlitt, and Peter Christian Skovgaard.

scholarly journals On the Interaction Between Tectonic Processes of the Earth and the Moon

1972 ◽  
Vol 47 ◽  
pp. 220-225
Author(s):  
N. A. Kozyrev
Keyword(s):  
Causal Relation ◽  
Direct Interaction ◽  
Tectonic Activity ◽  
Irreversible Processes ◽  
The Moon ◽  
Tidal Forces ◽  
Tectonic Processes ◽  
The Earth ◽  
History Of ◽  
Celestial Bodies

At present seismographs are operating on the Moon as well, installed there owing to the successful Apollo missions. However these data are insufficient for detailed statistic investigations. That is why in case of the Moon we are to use indirect indications of its activity, such as the data on transient light phenomena from the catalogues by Miss B. Middlehurst. Among the great number of earthquakes there were chosen only the strong earthquakes (magnitude 6.5) with focuses deeper than 70 km. According to these characteristics 630 earthquakes were selected from 1904 to 1967. In the Middlehurst catalogue during the same period about 370 transient events on the Moon are registrated. A distribution of lunar events on the days of an anomalistic month gives evidence of the influence of the Earth's tidal forces (the Middlehurst effect). It appears that the distribution of earthquakes gives a similar curve. Thus the tidal interaction of the Earth and the Moon establishes certain synchronism in tectonic activity of these planets. The further statistic analysis reveals some more causal relation between the processes of the Earth and the Moon. Strongly pronounced maximum of lunar events is observed with the interval of 2–3 days after the earthquakes and the maximum of earthquakes – with quite the same interval after the lunar events. The peaks of these maxima exceed the mean number of events by a factor 3. The Moon Earth system is the astronomical example of a direct interaction of the processes in the neighbouring celestial bodies.The corresponding experiments, made at the Pulkovo Observatory, confirm the possibility of immediate interactions of irreversible processes due to the change of physical properties of time. Thus we can form a chronology of orogenesis on the Moon judging from the data on the history of the Earth. Tectonic processes of the Earth and the Moon seem to be in such a close interaction as if the Moon were in direct contact with the Earth, i.e. in other words, were its seventh continent. These conclusions give evidence of the extreme importance of regular seismic observations on the Moon.

scholarly journals Knowing and doing in the sixteenth century: what were instruments for?

2003 ◽  
Vol 36 (2) ◽  
pp. 129-150 ◽  
Author(s):  
JIM BENNETT
Keyword(s):  
Sixteenth Century ◽  
Natural World ◽  
History Of Astronomy ◽  
Scientific Instruments ◽  
Online Database ◽  
The Earth ◽  
History Of ◽  
Practical Mathematics ◽  
The Relationship

Despite recent work on scientific instruments by historians of science, the meeting ground between historians and curators of collections has been disappointingly narrow. This study offers, first, a characterization of sixteenth-century mathematical instruments, drawing on the work of curators, as represented by the online database Epact. An examination of the relationship between these instruments and the natural world suggests that the ‘theoric’, familiar from studies of the history of astronomy, has a wider relevance to the domain of practical mathematics. This outcome from a study of collections is then used in re-examining an established question in the history of science, the position of William Gilbert on the motion of the Earth.

scholarly journals Utilização de veículos alternativos de comunicação para a difusão do conhecimento paleontológico

2007 ◽  
Vol 30 (1) ◽  
pp. 168-174
Author(s):  
Ana Carolina Gelmini de Faria ◽  
Ana Carolina Maciel Vieira ◽  
Deusana Maria da Costa Machado ◽  
Juliana Silva de Matos ◽  
Luiza Corral Martins de Oliveira Ponciano ◽  
...  
Keyword(s):  
Natural Resources ◽  
Rio De Janeiro ◽  
Evolutionary Process ◽  
Cultural Formation ◽  
Geologic Time ◽  
The Earth ◽  
New Process ◽  
History Of ◽  
New Look

Paleontology teaching must be an usual subject in the cultural formation. It is from it that man understands the history of Earth and its evolutionary process, giving a new look and perspective of what behaviors a society must adopt. In order that teaching of paleontology subjects gets a response back from society, other methods beside the basic didactic books must be explored for diffusion of educational and informative message, whit less academic terms and more attractively. Searching alternatives to fill such necessities, some of the available options are: Games, expositions, animations/documentaries and paradidactic books. These media have already been used by many scholars in the area, but can always be reworked and explored. The Laboratório de Estudos de Comunidades Paleozóicas (LECP) of the Universidade Federal do Estado do Rio de Janeiro (UNIRIO) has been using one of these alternatives. It is a project of elaboration of paradidactic books that a language directed to the infant-juvenile people was adopted to introduce paleontological concepts and fossiliferous localities - Maecuru e Ererê Formations (Amazonas Basin) - from Devonian Period. The referred project, although using a resource already available in Paleontology teaching, is innovator, because it deals with Brazilian formations of a geologic period unknown by the population. By alternative educational proposes the paleontology consolidates new process of interdisciplinary, necessary for diversified divulgation of its subjects. This new paleontology vision, when assimilated by the society, allow a conscientization about the biologics and non-biologics process that have occurred along the geologic time. A holistic conscience of the evolution of the Earth would help in the formation of a new society, which is already worrying about the balance and availability of the natural resources.

Political Geology

Geography ◽  
2021 ◽  
Author(s):  
Adam Bobbette
Keyword(s):  
Science And Technology Studies ◽  
Religious Studies ◽  
Resource Extraction ◽  
Earth System ◽  
Geological Material ◽  
Geological Process ◽  
The Earth ◽  
History Of ◽  
Geological Sciences ◽  
The Relationship

Political geology is concerned with the relationship between geological process, matter, and politics. It is a relatively recent neologism adopted by geographers and includes scholarship from a number of disciplines adjacent to geography, including anthropology, history of science, science and technology studies, and religious studies. The emergence of the Anthropocene no doubt played a role in raising geographers’ interest in the politicization of geology and geological knowledge. Much work in the field has begun to depart from the lens of Anthropocene studies and venture into new intellectual territory. Political geology seeks to understand geological knowledge as a tradition with histories and geographies. It studies the history of the geological sciences across world cultures and has an expanded conception of geological knowledge (and the sciences) beyond a focus on Euro-America. It is building a cosmopolitan understanding of the geological sciences. Geological knowledge is not taken for granted to speak for the earth system but is placed in its cultural, technological, and political context. At the same time, political geologists are concerned with the vibrant, lively materiality of geology. They are interested in Earth’s capacity to act upon politics and create political cultures. A renewed attention to the agency of geology has resulted in a number of papers that stress the ‘geo’ in geopolitics—the grounded, material dimension that situates all and any politics. There has therefore been an uptick in scholarship on verticality, depth, and resource extraction that foregrounds the material agency of geological process. This has been further brought together with consideration of the multiple knowledge traditions that claim to know and represent geological material. The conventional distinctions between geology and spirituality, geological sciences and religion, organic and inorganic, have been questioned. Alternative modes of writing about geology and the sciences are being explored through performance, fiction, sculpture, and poetry. Political geological scholarship thus brings together a number of discussions about the intersections among knowledge, Earth, power and governance. What follows is a broad introduction and survey of the key formative works of political geology, histories of geological knowledge, theoretical preoccupations, and sites of interest to political geologists. The theory and sites sections are ordered alphabetically.

scholarly journals Good vibrations: living with the motions of our unsettled planet

2020 ◽  
Vol 3 (2) ◽  
pp. 303-327
Author(s):  
Tamsin Badcoe ◽  
Ophelia Ann George ◽  
Lucy Donkin ◽  
Shirley Pegna ◽  
John Michael Kendall
Keyword(s):  
Interdisciplinary Approach ◽  
Tectonic Activity ◽  
Broadband Seismometer ◽  
The Earth ◽  
History Of ◽  
Convective Motions ◽  
And Performance ◽  
The University ◽  
The City ◽  
Large Earthquakes

Abstract. By its very nature Earth is unsettled and in continual motion. Earthquakes and volcanoes are an expression of the convective motions of the planet, and our existence on Earth is a consequence of this tectonic activity. Yet, as humans, we often struggle to understand our role in relation to such unpredictable natural phenomena and use different methods to attempt to find order in nature's chaos. In dwelling on the surface of our “unsettled planet”, we adapt and live with a range of ground vibrations, both natural and anthropogenic in origin. Our project, funded by the University of Bristol's Brigstow Institute, seeks to explore how we perceive and understand the shaky ground we live on, using an interdisciplinary approach that brings together the Earth sciences, the history of art and literature, and performance art. Inspired by historical commentary in the aftermath of large earthquakes, which frequently notes the unscheduled ringing of church bells excited by the shaking around them, we reflect on how these purported unscheduled bell-ringing events were caused not only by near earthquakes but also by distant incidents. To investigate this phenomenon, we installed a state-of-the-art broadband seismometer in the Wills Memorial Building tower to record how Great George (the tower bell) responds to the restless world around him. The installed seismometer has been recording activity around and within the tower on a near-continuous basis between late-March 2018 and January 2019. Here, we present the signals recorded by the seismometer as Great George overlooks the hustle and bustle of the city around him and investigate how connected we are to our unsettled planet, even from our tectonically quiet setting in Bristol. We find that the seismometer not only shows the ebb and flow of activity in and around Bristol but also registers earthquakes from as nearby as Lincolnshire, UK, or as far away as Fiji, halfway around the world. In order to contextualize our findings, our project also considers what determines how people have responded to earth-shaking events, drawing on both historical and recent examples, and looks to contemporary art practice to consider how an awareness of our unsettled planet can be communicated in new ways. The project has led to a number of art installations and performances, and feedback from artists and audiences shows how making art can be used to both investigate our connections with the Earth and to articulate (and even accept) the uncertainties inherent in encountering unstable ground.

scholarly journals Argon constraints on the early growth of felsic continental crust

2020 ◽  
Vol 6 (21) ◽  
pp. eaaz6234 ◽  
Author(s):  
Meng Guo ◽  
Jun Korenaga
Keyword(s):  
Continental Crust ◽  
Mantle Convection ◽  
Thermal Evolution ◽  
Early Growth ◽  
Early Earth ◽  
Crustal Growth ◽  
Crustal Recycling ◽  
Consistent Manner ◽  
History Of ◽  
Surface Environment

The continental crust is a major geochemical reservoir, the evolution of which has shaped the surface environment of Earth. In this study, we present a new model of coupled crust-mantle-atmosphere evolution to constrain the growth of continental crust with atmospheric 40Ar/36Ar. Our model is the first to combine argon degassing with the thermal evolution of Earth in a self-consistent manner and to incorporate the effect of crustal recycling and reworking using the distributions of crustal formation and surface ages. Our results suggest that the history of argon degassing favors rapid crustal growth during the early Earth. The mass of continental crust, highly enriched in potassium, is estimated to have already reached >80% of the present-day level during the early Archean. The presence of such potassium-rich, likely felsic, crust has important implications for tectonics, surface environment, and the regime of mantle convection in the early Earth.

Synthesis and Future Directions

2007 ◽  
Author(s):  
Earl B. Alexander ◽  
Roger G. Coleman ◽  
Todd Keeler-Wolfe ◽  
Susan P. Harrison
Keyword(s):  
North America ◽  
Continental Crust ◽  
Ultramafic Rocks ◽  
Western North America ◽  
Ocean Crust ◽  
The Earth ◽  
History Of ◽  
Serpentine Vegetation ◽  
Oceanic Plates ◽  
Eukaryotic Organisms

Ultramafic rocks come from deep within the earth. Most rocks on the surface of the earth are quite different from them. Unique rocks make unique soils and support special plants. Exploring the links and interactions among these unique rocks, soils, and vegetation is an interdisciplinary endeavor that has been accomplished by experts in three areas. It has helped elucidate serpentine rock–soil–plant relationships and provide a rationale for the unusual soil properties and vegetation associated with ultramafic rocks. Examples from arctic tundra to temperate rainforest and hot desert in western North America provide a framework for the investigation of serpentine geoecosystems around the world. The unusual character of most serpentine vegetation is readily apparent even to an untrained eye. Although a vast number of rock and soil types make up the earth’s surface, few have as dramatic and visible effects on ecosystems as do ultramafic, or serpentine materials. Most ultramafic rocks in western North America have been derived from the mantle of earth via ocean crust. Magnesium is highly concentrated in the mantle and calcium, potassium, and phosphorous are relatively low. Calcium and potassium are further depleted from peridotite in the partial melting of ultramafic rock at the base of the ocean crust. As oceanic plates drift from spreading centers, most of the ocean crust is subducted and returns to the mantle (chapter 2). Only relatively small fragments of ocean crust are added to the continents. Because eukaryotic organisms, from protozoa to plants and animals, have evolved on continental crust, they are adapted to soils with higher concentrations of calcium, potassium, and phosphorus (elements with higher concentrations in continental crust than in ultramafic rocks from the base of the ocean crust) and much lower concentrations of magnesium. Having evolved on continents, plants depend on relatively high ratios of calcium and potassium to magnesium, elements that they use for a wide range of physiological functions. Although there has been a long history of evolutionary adaptation to the chemistry of the continental crust, special adaptations have allowed some plants to colonize the atypical conditions of serpentine.

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