scholarly journals On the Devonian age of the World

The Geologist ◽  
1861 ◽  
Vol 4 (8) ◽  
pp. 332-347
Author(s):  
W. Pengelly
Keyword(s):  
Thermal Conditions ◽  
The Sun ◽  
Geological History ◽  
Geological Time ◽  
The Earth ◽  
The World ◽  
Astronomical Time ◽  
History Of ◽  
Time Required ◽  
Devonian Age

The rooks composing the earth's crust contain a history and represent time—a history of changes numerous, varied, and important: changes in the distribution of land and water; in the thermal conditions of the world; and in the character of the organic tribes which have successively peopled it. The time required for these mutations must have been vast beyond human comprehension, requiring, for its expression, units of a higher order than years or centuries. In the existing state of our knowledge it is impossible to convert geological into astronomical time: it is at present, and perhaps always will be, beyond our power to determine how many rotations on its axis, or how many revolutions round the sun the earth made between any two recognised and well-marked events in its geological history. Nevertheless it is possible, and eminently convenient, to break up geological time into great periods: it must not be supposed, however, that such periods are necessarily equal in chronological, organic, or lithological value; or separated from one another by broadly marked lines of demarcation; or that either their commencements or terminations in different and widely separated districts were strictly synchronous.One of the terms in the chronological series of the geologist is known as the Devonian, that which preceeded it the Silurian, and the succeeding one the Carboniferous period; and these, with some others of less importance, belong to the Palæozoic or ancient-life epoch, or group of periods.

A Discussion on the evolution of the Precambrian crust - Introductory remarks

1973 ◽  
Vol 273 (1235) ◽  
pp. 316-316 ◽  
Keyword(s):  
Early History ◽  
Geological Time ◽  
Precambrian Rocks ◽  
The Past ◽  
Geological Processes ◽  
The Earth ◽  
Large Numbers ◽  
The World ◽  
History Of

The realization that the behaviour of the Earth has changed radically during geological time has come about largely in the last decade. This development, which constitutes one of the major advances in geological thinking, results from the study of Precambrian phenomena in many parts of the world and in particular from the work of a small number of geochronologists. In the last ten years as large numbers of unfossiliferous Precambrian rocks have been dated, it has become clear that the nature of geological processes has varied throughout geological time and that one of the cardinal doctrines of geology - the concept that the present is the key to the past — could not be applied to the study of the early history of the Earth.

Conclusion

2021 ◽  
pp. 177-188
Author(s):  
Beth Cykowski
Keyword(s):  
Human Existence ◽  
Human Beings ◽  
Geological Time ◽  
The Earth ◽  
The World ◽  
History Of ◽  
Mode Of Being ◽  
Do So

Heidegger argues in The Fundamental Concepts of Metaphysics (FCM) that the world of Dasein is not a neat capsule of entities that are always available; it is ‘ruptured’ by a fundamental finitude that impels it to develop its own anchoring in physis. The temporality of human existence is staged against the backdrop of absolute, geological time, the time of earthly entities, insofar as human beings are finite organisms that are temporally bounded to a particular lifespan. But this ‘terrestrial’ time is discernible only from the perspective of a mode of being that takes time as such into account. Our conceptions of the dawn of time and the timespan of the earth, as Schalow says, always ‘derive their relevance from Dasein’s mode of historicalness, and ultimately, from the history of being itself. To the extent that we can refer to “geological time”, a time of the earth, the ability to do so still hinges upon the possibility of an awareness of such terrestrial origins, of the ...

Geology and Evolution

2019 ◽  
pp. 75-106
Author(s):  
Bill Jenkins
Keyword(s):  
Natural History ◽  
Geological History ◽  
Geological Time ◽  
Directional Model ◽  
The Earth ◽  
Evolution Of Life ◽  
History Of ◽  
English Speaking ◽  
English Speaking World ◽  
Life On Earth

The dominant school of geology in Edinburgh in the early nineteenth century was that of the followers of the German mineralogist Abraham Gottlob Werner. His most important disciple in the English-speaking world was Edinburgh’s professor of natural history, Robert Jameson. The Wernerians believed that the history of the earth was fundamentally directional; they believed the earth started out as a ball of hot fluid from which the different rocks that now form the crust of the planet gradually precipitated out over geological time. It is argued in this chapter that this directional model of the geological history of the earth was peculiarly compatible with a progressive model of the history of life on earth. The changes in the physical condition of the earth over geological time were seen by some Wernerian geologists as driving the evolution of life.

REFERENCE POINT OF GEOLOGICAL TIME

2021 ◽  
Vol 43 (2) ◽  
pp. 172-184
Author(s):  
Gennady Aksenov ◽  
Keyword(s):  
Earth Sciences ◽  
Reference Point ◽  
Geological History ◽  
Geological Time ◽  
Biological Time ◽  
Mineral Complex ◽  
The Earth ◽  
History Of ◽  
Absolute Age ◽  
The Universe

In the earth sciences, there is a persistent contradiction between modern ideas about the age of the planet and the concept of V.I. Vernadsky about the geological eternity of life. According to Vernadsky, the absolute age of the rock indicates only the time of its last metamorphism, but not the age of the Earth. It is no coincidence that the pregeological substance of a cosmic formation of the planet has not been found. Such substance does not exist because any mineral complex and rock begins to form in the hypergenesis zone. Vernadsky argued that geological history was equal in duration to the existence of the biosphere and its duration was measured by biological time. His concept is confirmed by current biogeochemistry. The history of the biosphere practically coincided with the "canonical" age of the Earth. In a cosmological sense, the picture of the universe cannot be built without the concept of the geological eternity of the biosphere.

I. On Professor Haughton's estimate of geological time

1878 ◽  
Vol 27 (185-189) ◽  
pp. 179-183 ◽  
Keyword(s):  
Royal Society ◽  
Principal Axis ◽  
Present Note ◽  
Geological History ◽  
Geological Time ◽  
Axis Of Rotation ◽  
The Earth ◽  
History Of ◽  
Set Up ◽  
Instantaneous Axis

In a paper recently read before the Royal Society, Professor Haughton has endeavoured by an ingenious line of argument to give an estimate of the time which may have elapsed in the geological history of the earth. The results attained by him are, if generally accepted, of the very greatest interest to geologists, and on that account his method merits a rigorous examination. The object, therefore, of the present note is to criticise the applicability of his results to the case of the earth; and I conceive that my principal criticism is either incorrect, and will meet its just fate of refutation, or else is destructive of the estimate of geological time. Professor Haughton’s argument may be summarised as follows:— The impulsive elevation of a continent would produce a sudden displacement of the earth’s principal axis of greatest moment of inertia. Immediately after the earthquake, the axis of rotation being no longer coincident with the principal axis, will, according to dynamical principles, begin describing a cone round the principal axis, and the complete circle of the cone will be described in about 306 days. Now, the ocean not being rigidly connected with the nucleus, a 306-day tide will be established, which by its friction with the ocean bed will tend to diminish the angle of the cone described by the instantaneous axis round the principal axis: in other words, the “wabble” set up by the earthquake will gradually die away.

scholarly journals III. On the nature and construction of the sun and fixed stars

1795 ◽  
Vol 85 ◽  
pp. 46-72 ◽  
Keyword(s):  
Central Body ◽  
Planetary System ◽  
Considerable Progress ◽  
The Sun ◽  
Great Satisfaction ◽  
The Earth ◽  
The World ◽  
Celestial Bodies ◽  
The Universe ◽  
Made In

Among the celestial bodies the sun is certainly the first which should attract our notice. It is a fountain of light that illuminates the world! it is the cause of that heat which main­tains the productive power of nature, and makes the earth a fit habitation for man! it is the central body of the planetary system; and what renders a knowledge of its nature still more interesting to us is, that the numberless stars which compose the universe, appear, by the strictest analogy, to be similar bodies. Their innate light is so intense, that it reaches the eye of the observer from the remotest regions of space, and forcibly claims his notice. Now, if we are convinced that an inquiry into the nature and properties of the sun is highly worthy of our notice, we may also with great satisfaction reflect on the considerable progress that has already been made in our knowledge of this eminent body. It would require a long detail to enumerate all the various discoveries which have been made on this subject; I shall, therefore, content myself with giving only the most capital of them.

The Strait of Magellan—a Gateway to New Worlds

2021 ◽  
Author(s):  
Mauricio Onetto Pavez
Keyword(s):  
Global Scale ◽  
Modern World ◽  
American Continent ◽  
The Earth ◽  
Starting Point ◽  
Strait Of Magellan ◽  
The World ◽  
The Strait Of Magellan ◽  
History Of ◽  
First Time

The year 2020 marks the five hundredth anniversary of the “discovery” of the Strait of Magellan. The unveiling of this passage between 1519 and 1522 allowed the planet to be circumnavigated for the first time in the history of humanity. All maritime routes could now be connected, and the idea of the Earth, in its geographical, cosmographic, and philosophical dimensions, gained its definitive meaning. This discovery can be considered one of the founding events of the modern world and of the process of globalization that still continues today. This new connectivity awoke an immediate interest in Europe that led to the emergence of a political consciousness of possession, domination, and territorial occupation generalized on a global scale, and the American continent was the starting point for this. This consciousness also inspired a desire for knowledge about this new form of inhabiting the world. Various fields of knowledge were redefined thanks to the new spaces and measurements produced by the discovery of the southern part of the Americas, which was recorded in books on cosmography, natural history, cartography, and manuscripts, circulating mainly between the Americas and Europe. All these processes transformed the Strait of Magellan into a geopolitical space coveted by Europeans during the 16th century. As an interoceanic connector, it was used to imagine commercial routes to the Orient and political projects that could sustain these dynamics. It was also conceived as a space to speculate on the potential wealth in the extreme south of the continent. In addition, on the Spanish side, some agents of the Crown considered it a strategic place for imperial projections and the defense of the Americas.

LEONARDO DA VINCI’S AND NICOLAUS STENO’S GEOLOGY

2021 ◽  
Vol 40 (2) ◽  
pp. 293-331
Author(s):  
GIAN BATTISTA VAI
Keyword(s):  
Comparative Evaluation ◽  
Geological History ◽  
Basic Principles ◽  
Founding Fathers ◽  
Angular Unconformity ◽  
Geologic Time ◽  
The Earth ◽  
Relative Chronology ◽  
History Of ◽  
Do So

Anniversaries for the two founding fathers of geology occurring in the same year prompted a comparative evaluation of how the two contributed to establishing the basic principles of the discipline. To do so, passages from their publications, codices and manuscripts have been quoted directly. The Stenonian principles (‘original horizontality’, ‘original continuity’, and ‘superposition of individual strata’) are present in Leonardo’s notebooks amazingly formulated, using similar wording when studying the same area more than 150 years earlier. Also, Stenonian priority in naming and explaining geological concepts and processes (e.g., faulting, folding, angular unconformity, relative chronology) are mirrored in Leonardo’s writings and pictorial works. While Steno enjoys priority in stepwise restoration of the geological history of a given region, Leonardo was the first to construct a 3D geological profile representation and geomorphologic maps. Lastly, the paper focuses on diverging stances of the two savants about the Noachian Deluge and the age of the Earth. Already 500 years ago, Leonardo had solved the question of marine fossil remains of organic origin found in the mountains implying the possibility of deep geologic time in a statement of ‘eternalism’. 350 years ago, Steno solved the same question in a different way in which he retained a basic role for the Deluge and assumed a short age for the Earth by focusing mainly on short-lived sedimentary and geomorphologic processes.

Flights of Imagination: Avicenna’s Phoenix (ʿAnqā) and Bedil’s Figuration for the Lyric Self

2020 ◽  
Vol 2 (1) ◽  
pp. 28-72
Author(s):  
Jane Mikkelson
Keyword(s):  
First Person ◽  
The Sun ◽  
The Moon ◽  
The Earth ◽  
Philosophical System ◽  
Personal Experiences ◽  
The World ◽  
The Phoenix

Abstract The phoenix (ʿanqā) appears in the philosophy of Avicenna (d.1037) as his example of a “vain intelligible,” a fictional being that exists in the soul, but not in the world. This remarkable bird is notable (along with the Earth, the moon, the sun, and God) for being a species of one. In this essay, I read the poetry Bedil of Delhi (d.1720) in conversation with the philosophical system of Avicenna, arguing that the phoenix in Bedil’s own philosophical system functions as a key figuration that allows him simultaneously to articulate rigorous impersonal systematic ideas and to document his individual first-personal experiences of those ideas. The phoenix also plays a metaliterary role, allowing Bedil to reflect on this way of doing philosophy in the first person—a method founded on the lyric enrichment of Avicennan rationalism. Paying attention to the adjacencies between poetry and philosophy in Bedil, this essay traces the phoenix’s transformations from a famous philosophical example into one of Bedil’s most striking figurations in his arguments about imagination, mind, and self.

scholarly journals XIII. On the precession of a viscous spheroid, and on the remote history of the Earth

1879 ◽  
Vol 170 ◽  
pp. 447-538 ◽  
Keyword(s):  
Relative Motion ◽  
Mass Motion ◽  
The Sun ◽  
The Earth ◽  
Bodily Tides ◽  
History Of ◽  
The Subject ◽  
Theoretical Dynamics

The following paper contains the investigation of the mass-motion of viscous and imperfectly elastic spheroids, as modified by a relative motion of their parts, produced in them by the attraction of external disturbing bodies; it must be regarded as the continuation of my previous paper, where the theory of the bodily tides of such spheroids was given. The problem is one of theoretical dynamics, but the subject is so large and complex, th at I thought it best, in the first instance, to guide the direction of the speculation by considerations of applicability to the case of the earth, as disturbed by the sun and moon.

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