scholarly journals III. On the origin of the parallel roads of Lochaber, and their bearing on other phenomena of the glacial period

1879 ◽  
Vol 29 (196-199) ◽  
pp. 6-21 ◽  
Keyword(s):  
Cold Period ◽  
Glacial Period ◽  
Glacial Deposits ◽  
Subsequent Determination ◽  
The One

Of the various hypotheses that have been brought forward since the time of Macculloch and Dick-Lauder to account for the origin of the Parallel Roads of Glen Roy, the one so ably propounded by Mr. Jamieson, in 1863, has been most generally received and adopted. It is a modification of the views originally expressed by Agassiz, to the effect that the barriers of the lakes,—to the shore action of which both the above-named geologists attributed the “roads,” but were at a loss to account both for the formation and removal of barriers,—had been formed during the glacial period by glaciers issuing from Glen Treig and Glen Arkaig, supplemented by others from Ben Nevis. The subsequent determination, by the Scotch geologists, of an intermediate milder period succeeded by a second cold period, led Mr. Jamieson, with whom the preglacial and glacial deposits of Scotland had been a subject of especial investigation, to conclude that the extension of these two glaciers took place during the second cold period, which he thinks was of little less intensity than the first, and that, while the glacier from Glen Arkaig blocked up Glen Gluoy, the glacier from Glen Treig formed a barrier to Glen Roy.

Duration of the phase of preservation and destruction in cases of deposits of iced categories of SHP (spontaneous) in the territory of Ukraine in the month of the cold period of the year during 1991–2016

2020 ◽  
Vol 99 (1-2) ◽  
pp. 62-72
Author(s):  
Svitlana Pyasetska
Keyword(s):  
Ice Cream ◽  
Cold Period ◽  
Maximum Diameter ◽  
Glacial Deposits ◽  
Previous Period ◽  
Significant Duration ◽  
Clay Deposits ◽  
The Individual

The article deals with the question of the duration of the preservation and destruction phase which were calculated for ice-free periods of the category of SHP and were observed on the territory of Ukraine in the month of the cold period of the year during certain periods 1991–2000, 2001-2010 and 2011-2016. It was established that the duration of the preservation phase and the destruction of ice-oily deposits in the category of SHP is very volatile and ranges from near-instant destruction after reaching a maximum diameter of several hours or several dozen hours. However, there are cases where the duration of this phase can be 4 days in a row and more than several hundred hours. The study found that for the most part during the investigated period, the glacial deposits of the SHP category were dominated by non-prolonged conservation and degradation phases, regardless of the region where the sediment was formed, and regardless of the overall duration of the sediment itself, which could be significant. In 2001–2010 and 2011–2016, unlike in the period of 1991-2000, in January and December, the number of cases of ice-ousted categories of SHP increased. Moreover, in January, especially in 2011–2016, the number of cases with a significant duration of the phase of preservation and destruction of ice deposits of the category of SHP was increased. From the above we can draw a number of conclusions, namely: – During 1991–2000, the phases of preservation and destruction of ice-clay deposits in the category of HPAs were mostly non-prolonged and ranging from several hours to several dozen hours. The most prolonged phases of preservation and destruction of deposits of iced ice of category SHHA were in cases of sediments in Lower Zirgozakh in January 1996, in March 1998 in Kropivnitsky and most often in November 1999 in Gadyach, Dolynska, Komissarivka, Mariupol, Prisheby, and also in 2000 It is in Novodnistrovsk, Separate, Lyubashevtsi, Serbs, Voznesensk, December 1997 in Loshkarivka, Kryvy Rih, Nikopol, Lyubashevtsi, Prisheb and especially in Donetsk. – In 2001–2010, the amount of ice-cream deposits in the category of SHP increased slightly. In addition, the duration of the preservation and destruction phase compared to the previous period changed slightly, taking into account the individual months. So, in January, along with the relatively long phases of preservation and destruction of ice-clay deposits of the category of SHP (up to several dozen hours), in 2010 deposits with very long phases of conservation and destruction in Debaltsevo and especially in Mysovoye were observed. In December of this period, the long phases of preservation and destruction of deposits of iced ice of category SHP were observed in 2004 in Dar’yivka, and in 2008 in Vinnitsa and Ovruch. In the remaining months, the duration of the conservation and destruction phase was overwhelmingly within a few hours, at least to several dozen golds (11–25 hours) – Unlike in the years 1991-2000 and 2001-2010, in January the number of cases of ice deposits of the category of SHP increased in the five-year period of 2011–2016. They met practically in most regions. Significantly increased cases with them, where the duration of the preservation and destruction phase was significant and exceeded the duration of 4 consecutive days. Such cases were observed in January 2013 in Rava-Ruska, Kamianets Buzka and Poltava, in January 2014 – in Rava-Ruska, Ternopil, Amvrosiyivka, Rosdilna, Mykolayiv, Ochakov, and Simferopol. In December 2012, a similar accident happened in Evpatoria.

I.—On the Sands and Gravels Intercalated in the Boulder-clay

1891 ◽  
Vol 8 (8) ◽  
pp. 337-348
Author(s):  
G. W. Bulman
Keyword(s):  
Ice Sheets ◽  
The Other ◽  
Cold Period ◽  
Glacial Geology ◽  
Boulder Clay ◽  
The One

The interpretation of the sands and gravels intercalated in the glacial drift is one of the most interesting problems in glacial geology. Do they, on the one hand, represent the deposits of one or more mild intervals alternating with periods of intense cold; or were they, on the other, laid down during one continuous cold period marked by such slight oscillations as can be shown to occur in connection with existing glaciers and ice-sheets?

scholarly journals Natural periodicities and Northern Hemisphere–Southern Hemisphere connection of fast temperature changes during the last glacial period: EPICA and NGRIP revisited

2014 ◽  
Vol 10 (5) ◽  
pp. 1751-1762 ◽  
Author(s):  
T. Alberti ◽  
F. Lepreti ◽  
A. Vecchio ◽  
E. Bevacqua ◽  
V. Capparelli ◽  
...  
Keyword(s):  
Ice Core ◽  
Data Sets ◽  
Time Behavior ◽  
Glacial Period ◽  
Last Glacial Period ◽  
Last Glacial ◽  
Mode Decomposition ◽  
Cross Correlation Analysis ◽  
The One ◽  
The Last Glacial

Abstract. We investigate both the European Project for Ice Coring in Antarctica Dronning Maud Land (EDML) and North Greenland Ice-Core Project (NGRIP) data sets to study both the time evolution of the so-called Dansgaard–Oeschger events and the dynamics at longer timescales during the last glacial period. Empirical mode decomposition (EMD) is used to extract the proper modes of both the data sets. It is shown that the time behavior at the typical timescales of Dansgaard–Oeschger events is captured through signal reconstructions obtained by summing five EMD modes for NGRIP and four EMD modes for EDML. The reconstructions obtained by summing the successive modes can be used to describe the climate evolution at longer timescales, characterized by intervals in which Dansgaard–Oeschger events happen and intervals when these are not observed. Using EMD signal reconstructions and a simple model based on the one-dimensional Langevin equation, it is argued that the occurrence of a Dansgaard–Oeschger event can be described as an excitation of the climate system within the same state, while the longer timescale behavior appears to be due to transitions between different climate states. Finally, on the basis of a cross-correlation analysis performed on EMD reconstructions, evidence that the Antarctic climate changes lead those of Greenland by a lag of ≈ 3.05 kyr is presented.

scholarly journals On the Glacial Drift of Furness, Lancashire

The Geologist ◽  
1864 ◽  
Vol 7 (6) ◽  
pp. 209-217
Author(s):  
E. Hodgson.
Keyword(s):  
Rock Surface ◽  
Glacial Period ◽  
Glacial Deposits ◽  
South Eastern ◽  
Upper Silurian ◽  
Carboniferous Limestone

The following sketch of the glacial deposits of Furness is not pretended to be complete ; it is, in fact, nothing but a sketch: neither can it presume to be free from errors. The marine drift, especially, has not received all the attention it demands, but will, I hope, with the clays and peats of Furness, form a subject for a future memoir. The deposits in the section are referred doubtfully to their periods.Striated Bock Surfaces.—The district of Furness; its south-eastern part, however, does not perhaps present so many of those remarkable records of the glacial period, the striated rock-surfaces, as are to be met with in more mountainous districts. The rocks, especially the Carboniferous Limestone and Permian formations, either lie in agreat measure hidden under a thick covering of deposits, or, as in the hills of the Upper Silurian strata, are of such a soft decomposing nature, that they retain very little primitive facing.Occasionally, however, striations may be found. A little way in shore, west from the estuary of the Crake, at the head of Morecambe Bay, a rock-surface recently exposed by the removal of the overlying material, and now quarried away, showed a series of parallel shallow groovings from an inch to an inch and a half apart; the intervening spaces plane and smoothed, and having very fine striæ. The striæ and grooving had a direction from E. to W., or perhaps a little N.E. to S.W.

The development and function of the rumen in milk-fed calves

1959 ◽  
Vol 52 (1) ◽  
pp. 72-78 ◽  
Author(s):  
R. H. Smith
Keyword(s):  
Body Weight ◽  
Polyethylene Glycol ◽  
Small Extent ◽  
The Other ◽  
Subsequent Determination ◽  
Different Ages ◽  
Unit Body Weight ◽  
The One ◽  
And Function

1. The volume of rumen liquor in milk-fed calves at different ages up to 32 weeks was estimated by injecting polyethylene glycol into the rumen and subsequently determining its concentration in the rumen liquor. This volume increased progressively with age in relation to unit body weight. The increase xswas approximately fourfold between 4–8 weeks on the one hand and 28–32 weeks on the other.2. The amount of milk entering the rumen during a feed was estimated at different ages up to 32 weeks by the subsequent determination of the volume and fat content of the rumen liquor. In the majority of cases less than 5% of the milk fed entered the rumen. There did not appear to be any increase in the quantities of milk entering the rumen as the calves got older.3. An estimate of the rate of flow of fluid into and out of the rumen (other than milk at feeding) was made by measuring the rate of disappearance of polyethylene glycol from the rumen. A mean figure of 255 ml./hr./100 kg. body weight s.d. ± 50 was obtained in this way. It is suggested that this value probably represents the rate of flow of saliva.4. Magnesium, in a concentration up to about 8 mg./100 ml. in the rumen liquor, did not appear to be absorbed to more than a small extent through the rumen wall.

IV.—On Changes of Climate during the Glacial Epoch

1871 ◽  
Vol 8 (90) ◽  
pp. 545-553 ◽  
Author(s):  
James Geikie
Keyword(s):  
Arctic Climate ◽  
Northern Europe ◽  
Short Paper ◽  
Glacial Period ◽  
Glacial Deposits ◽  
Arctic Condition ◽  
Glacial Epoch ◽  
Boulder Clay ◽  
Gradual Approach ◽  
Snow And Ice

If one were asked to put into a few words the general results which have been arrived at from a study of the Glacial deposits, he would probably say that these deposits gave evidence of a severe Arctic condition of things having obtained in this country,—that the gradual approach of this Arctic climate caused the disappearance from our area of the fauna and flora which had previously characterized it,—that during the continuance of the cold in Britain several speciesof mammalia appear to have died out in the more southern regions of Europe, whither they had migrated,—and that it was not until after our climate had become greatly ameliorated that these islands were visited by what are termed the “Post-glacial mammalia,” several species of which, however, had been denizens. of Britain and northern Europe inPre-glacial times. In short, our island, throughout the Glacial period proper, is commonly supposed to have remained a barren waste of snow and ice. But the evidence which has been accumulating during recent years will compel us, I believe, to modify materially these general inferences. So far from the Glacial epoch having been one long continuous age of ice, it would appear to have been broken up by many intervening periods of less Arctic, and even temperate conditions, during whichthe snow and ice disappeared from our low grounds, and the glaciers shrunk back into our mountain valleys. I speak, of course, of that portion of the Glacial epoch which was antecedent to the general submergence, and is represented by the Till or Boulder-clay of Scotland. la this short paper I propose to give an outline of the facts upon which these conclusions are based. But before doing so it may be well to point out the order of succession of the Scottish drift deposits, which is now no longer a matter of dispute. Beginning with the lower beds, we have the following sequence

scholarly journals Natural periodicities and north–south hemispheres connection of fast temperature changes during the last glacial period: EPICA and NGRIP revisited

2014 ◽  
Vol 10 (2) ◽  
pp. 1129-1152
Author(s):  
T. Alberti ◽  
F. Lepreti ◽  
A. Vecchio ◽  
E. Bevacqua ◽  
V. Capparelli ◽  
...  
Keyword(s):  
Ice Core ◽  
Langevin Equations ◽  
Glacial Period ◽  
Last Glacial Period ◽  
Last Glacial ◽  
Mode Decomposition ◽  
Cross Correlation Analysis ◽  
The One ◽  
Core Project ◽  
The Last Glacial

Abstract. We investigate both the European Project for Ice Coring in Antarctica (EPICA) and North Greenland Ice-Core Project (NGRIP) datasets to study the time evolution of the so-called Dansgaard–Oeschger events during the last glacial period. The Empirical Mode Decomposition (EMD) is used to extract the proper modes of both the datasets. It is shown that the time behaviour of Dansgaard–Oeschger events is captured by three EMD modes, while three more EMD modes can be used to describe the evolution at longer time scales. Using EMD signal reconstructions and a simple model based on the one-dimensional Langevin equations, it is argued that the occurrence of a Dansgaard–Oeschger event can be described as an excitation of the climate system within the same state, while the longer time scale behaviour appears to be due to transitions between different states. Finally, on the basis of a cross-correlation analysis performed on EMD reconstructions, evidence is presented that the Antarctic climate changes lead that of Greenland by a lag of ≈3.6 kyr.

Note on Selection of Coordinate Systems for Geodynamics

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen
Keyword(s):  
Sea Level ◽  
The Other ◽  
Coordinate Systems ◽  
Mean Sea Level ◽  
The Earth ◽  
The One ◽  
Static Systems ◽  
Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

Nucleation of Disorder in Fe3Al Alloys

1967 ◽  
Vol 25 ◽  
pp. 312-313
Author(s):  
P. R. Swann ◽  
W. R. Duff ◽  
R. M. Fisher
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Annealing Temperature ◽  
Antiphase Domain ◽  
Effect Of Temperature ◽  
Domain Structures ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Higher Temperature ◽  
The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

Fundamental Research into Thin Films in a Developing Country

1972 ◽  
Vol 30 ◽  
pp. 500-501
Author(s):  
J.A. Eades ◽  
E. Grünbaum
Keyword(s):  
Thin Films ◽  
Growth Process ◽  
Empirical Process ◽  
Nucleation And Growth ◽  
Research Groups ◽  
Film Research ◽  
Fundamental Research ◽  
Controlled Deposition ◽  
The One ◽  
The University

In the last decade and a half, thin film research, particularly research into problems associated with epitaxy, has developed from a simple empirical process of determining the conditions for epitaxy into a complex analytical and experimental study of the nucleation and growth process on the one hand and a technology of very great importance on the other. During this period the thin films group of the University of Chile has studied the epitaxy of metals on metal and insulating substrates. The development of the group, one of the first research groups in physics to be established in the country, has parallelled the increasing complexity of the field.The elaborate techniques and equipment now needed for research into thin films may be illustrated by considering the plant and facilities of this group as characteristic of a good system for the controlled deposition and study of thin films.

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