Добрый день, Коллеги. Важное сообщение, просьба принять участие. Музей Ферсмана ищет помощь для реставрационных работ в помещении. Подробности по ссылке
The Earth is more than four billion years old. Its history is documented by the rocks that form the Earth’s crust, which lies beneath our feet and can be structurally complex in some places. The time that has elapsed since the formation of our planet is infinitely long when compared to the age of the human lineage, and several methods make it possible for us to measure geological time. The study of fossils—the remains of animals and plants preserved in sedimentary rocks—allows us to recognize the order of events that have formed the Earth.
The characteristic white limestones that form the Chalk were deposited across much of northern Europe during the Upper Cretaceous, 100 to 65 million years ago. Although the Chalk is not normally rich in fossils, the preservation is often exquisite and specimens are relatively easy to prepare out from the matrix using needles and brushes or an air abrasive. This explains why the Chalk has been, and continues to be, a favourite formation of many fossil collectors. The extensive collections housed in museums are the result of persistent collecting over more than 150 years, though few were collected with the necessary detailed stratigraphical horizoning that is so essential to today's study of the Chalk fauna.
A work of this nature depends very heavily on one's fellow workers. We take this opportunity to thank those many people who have assisted us with advice, facilities, the loan of specimens, and helpful discussions over many years. We apologize to anyone who may have inadvertently been missed here. We especially would like to mention staff of the Natural History Museum, Dr С Patterson, Dr A. Milner, Dr M. K. Howarth, Dr P. D. Taylor, Dr A. Smith, Dr N. J. Morris and Mr R. J. Cleevely for allowing us to examine specimens in their care. Also, many thanks go to Dr B. M. Cox (British Geological Survey) and Dr J. K. Wright (Royal Holloway and Bedford College) for allowing us to use photographs. Professor J. H. Callomon (University College, London), Dr G. Chancellor (Peterborough City Museum), Mr Alan Dawn (Stamford), Dr D. T. Donovan (University College, London), Dr Tim Palmer (University of Wales at Aberystwyth), Dr Mike Barker (Portsmouth Polytechnic), Ms Liz Harper (Open University), Dr F. T. Fursich (University of Wurtzburg), and Dr R. G. Clements, Dr J. W. Faithfull and Mr R. Branson (Leicester University) all offered helpful advice. At Leicester Museum Dr M. A. Taylor and Dr A. Cruickshank offered helpful discussions on aspects of marine reptile paleobiology. We have also drawn heavily on data from Dr A. Williams and Dr I. St. J. Fisher, both of whom have made important contributions to our knowledge of the geochemistry of the Oxford Clay. Ms S. Button, Mr J. Taylor and Mr A. Lloyd assisted with diagrams. Mrs D. Туе and Mrs W. D. Hebden helped type manuscripts. Dr Alistair Crame (British Antarctic Survey) and Dr Ed. Jarzembowski acted on behalf of the Palaeontological Association.
With the decision to produce this guide book we very rapidly found that specimens of many of the fossils were not represented in our collections. To remedy this we undertook several field visits to enrich the collections at Leicester University and the Open University. We therefore thank the London Brick Company for permission to visit their brick pits, and in particular thank Mr P. Furr (LBC Bletchley), Mr Keith Morton (LBC Stewartby) and Mr A. Robinson (LBC Calvert) for their help.
Geophysical methods are based on studying the propagation of the different physical fields within the earth’s interior. One of the most widely used fields in geophysics is the electromagnetic field generated by natural or artificial (controlled) sources. Electromagnetic methods comprise one of the three principle technologies in applied geophysics (the other two being seismic methods and potential field methods). In this book the author presents both the foundations and the most recent achievements of electromagnetic geophysical methods in the framework of a unified systematic exposition.
It is easier to give examples of geological structures than to define them. The word 'structure' means 'that which is built or constructed'. Structural geologists use the word to signify something that has been produced by deformation; that is, by the action of forces on and within the Earth's crust. Structures consist of a geometric arrangement - of planes, lines, surfaces, rock bodies, etc. The form and orientation of this arrangement reflect the interaction between the deforming forces and the preexisting rock body. <...>
When earth material properties are constant in any of the cartesian variables then it is useful to Fourier transform (FT) that variable. In seismology, the earth does not change with time (the ocean does!) so for the earth, we can generally gain by Fourier transforming the time axis thereby converting time-dependent differential equations (hard) to algebraic equations (easier) in frequency (temporal frequency). In seismology, the earth generally changes rather strongly with depth, so we cannot usefully Fourier transform the depth axis and we are stuck with differential equations in . On the other hand, we can model a layered earth where each layer has material properties that are constant in . Then we get analytic solutions in layers and we need to patch them together. <...>
The basic material for this book has been accumulated from time to time over the author’s working lifetime of about 40 years. The rules-and-pairs approach to Fourier transforms has been employed with good effect in a wide variety of problems, from pulse Doppler radar spectra to delay compensation, and antenna array patterns to efficient clutter simulation. It has been found generally easy and effective, quickly yielding useful results and allowing the user to see clearly the relationships between functions and transforms, waveforms and spectra, rather than losing sight of these in the complexities of integration. It seemed that the benefits of this approach should be better known, and the initial intention was to produce a technical note for use by the author’s colleagues and successors. However, the interest shown and encouragement given by Artech House have been gratefully received, and the opportunity to publicize the technique more widely has been taken. The support of Roke Manor Research in providing the facilities and freedom to write this book is gratefully acknowledged, as are the backing of C. J. Tarran and the reviewing of S. H. W. Simpson. The final acknowledgment is to the publisher’s reviewer, remaining anonymous, who provided encouragement and useful comments.
How much should a good spectroscopist know about Fourier transforms? How well should a professional who uses them as a tool in his/her work understand their behavior? Our belief is, that a profound insight of the characteristics of Fourier transforms is essential for their successful use, as a superficial knowledge may easily lead to mistakes and misinterpretations. But the more the professional knows about Fourier transforms, the better he/she can apply all those versatile possibilities offered by them. <...>
Chapter 1 Complexity Concepts and Non-Integer Dimensions in Climate and Paleoclimate Research Reik V. Donner Chapter 2 Analysis of Fractal Dimension of the Wind Speed and Its Relationships with Turbulent and Stability Parameters
Manuel Tijera, Gregorio Maqueda, Carlos Yagüe and José L. Cano Chapter 3 Evolution of Cosmic System Noboru Tanizuka
The scale invariance of geological phenomena is one of the first concepts taught to a student of geology. It is pointed out that an object that defines the scale, i.e., a coin, a rock hammer, a person, must be included whenever a photograph of a geological feature is taken. Without the scale it is often impossible to determine whether the photograph covers 10 cm or 10 km. For example, self-similar folds occur over this range of scales.
