Florsch Nicolas - Everyday applied geophysics. Volume 2, Magnetics and electromagnetism

Nicolas Florsch

Frdric Muhlach

Michel Kammenthaler

Series Editor

Andr Mariotti

First published 2018 in Great Britain and the United States by ISTE Press Ltd and Elsevier Ltd

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ISBN 978-1-78548-280-9

Printed and bound in the UK and US

Andr Mariotti, Emeritus Professor at the Universit Pierre-et-Marie-Curie, Honorary member of the Institut Universitaire de France

The scientific books published by ISTE Press include a multidisciplinary series called Earth Systems Environmental Sciences , and it is in this context that today I present a work dedicated to geophysical prospecting and its applications, coordinated by Professor Nicolas Florsch.

Its title, Everyday Applied Geophysics , deserves to be explained in more detail.

First, we should recall the important role played in some scientific fields by the so-called amateurs. This is especially the case for astronomy, a field where a socioepistemology of amateur practices, whose main points can be summed up here, has been established. These amateurs are not organized to compete with professionals, as they evidently lack the skills and the necessary resources. However, this is not a case of popular science: their practices, beyond the understanding of the sky, stars and the universe, are active and mobilized by the desire to make discoveries. Astronomy is a science where amateurs can obtain significant observation data, which are very useful for scientists.

On a smaller scale, some amateurs, for example, are quite involved in electronics and radio communication.

However, so far this has not been the case for Everyday Applied Geophysics, a domain that has potentially numerous applications associated with the exploration of the near subsoil: looking for water, archeological remains, geological peculiarities, etc.

Moreover, making Everyday Applied Geophysics available for researchers based in developing countries is a challenge of the utmost importance.

The goal is to open this field and allow everyone to employ the tools and methods used for exploring the near subsoil in order to highlight reservoirs or flow paths, locate holes, define geological stratifications, follow pollution plumes, search for archeological remains, etc. If curious and exploring amateurs may be involved, the main objective of the scientific community of these countries, which needs financially and technologically affordable tools, is to implement cheap and unsophisticated methods and techniques that, nonetheless, will produce plenty of essential data.

Let us provide an example to illustrate this point. Some geophyscal devices cost up to tens of thousands of dollars (or euros) on the market; in this work, we will discover that with a few hundred euros, or even less, we can implement a system that, despite being naturally lower in terms of data acquisition, allows everyone to carry out actual and effective subsurface geophysical prospection.

This work will also focus on the issue of self-learning. The existing literature does not tackle practical aspects either in terms of material implementation or basic interpretation concepts (actual resolution of the methods, sensitivity, etc.). This work is also very useful insofar as it can solve the problem of signal acquisition: it provides open-source Arduino solutions, supported by a downloadable program, for data acquisition in the field.

Thus, this work, which is unique in its genre and accessible to everyone (with a few more technical and/or mathematical boxed passages), bridges a double gap in the existing scientific literature by:

• providing accessible tools for the exploration of the near subsoil: from tools to acquisition systems (the latter being available with the use of computers) including a guide of free programs;
• providing practical information for implementation that cannot be found in other works, such as the design of devices (from electrodes to current flow, for example to carry out an electrical survey), the protocol for the creation of geophysical maps, etc.

We hope that this work reaches its audience and that the scientists that played a part in it may thus contribute to the removal of the ideological barrier between the world of basic research carried out in the academic world and applied research, as the markedly ideological gap that divides these two communities has not been entirely bridged yet. Besides, helping the development of the environmental field should be invaluable for a large number of countries.