Geophysics: A Very Short Introduction

Very Short Introductions #560

by William Lowrie

Geophysics is the physics of the Earth. Central to the Earth Sciences today, it encompasses areas such as seismology, volcanism, plate tectonics, gravitational anomalies, and the Earth's magnetic field (present and past, as captured in rocks), all of which give clues to both the structure and the working of the Earth.In this Very Short Introduction, William Lowrie describes the internal and external processes that affect the planet, as well as the principles and methods of geophysics used to investigate them. He explains how analysis of the seismic waves produced in earthquakes reveals the internal structure of the Earth. Geophysicists have established that the greatest source of energy powering geological processes is the Earth's internal heat. Deep inside the Earth, the temperature is high enoughto produce a fluid outer core of molten iron. It is the motion in this molten iron layer that produces the Earth's magnetic field, which shields the planet against harmful radiation from the Sun and outer space, and thus makes the planet habitable. Lowrie describes how the magnetic field also magnetizesrocks during their formation, leaving a permanent record of the ancient field and its direction that geophysicists have learned to use to interpret past motions of the continents and tectonic plates. From analyses of Earth's deepest interior to measurements made from Earth-orbiting satellites, Lowrie shows how geophysical exploration is vitally important in the search for mineral resources, and emphasizes our need to understand the history of our planet and the processes that govern itscontinuing evolution.ABOUT THE The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost every subject area. These pocket-sized books are the perfect way to get ahead in a new subject quickly. Our expert authors combine facts, analysis, perspective, new ideas, and enthusiasm to make interesting and challenging topics highly readable.

Genres: Science, Physics, Nonfiction, Geology, Audiobook

160 pages, Kindle Edition

First published May 22, 2018

Reviews

[Div Patel · Rating 4 out of 5]

I managed to snag a Paleomagnetism research assistant position at my university, but, being the bumbling freshman/rising sophomore that I am, I was very out of the loop about a lot of the info pertaining to geomagnetism. The geomagnetism book my professor provided in preparation for the research also flew straight past my head.

Then I stumbled on this book at the local public library, and I must say it is an absolute gem. I went from knowing next to nothing about geophysics to developing a firm interest in the subject and a resolution to pursue a geophysics concentration with the Geology BS program that I'm in.

The book goes over all the major topics within geophysics including planetary formation, seismology, gravity, heat flow, and magnetic fields. The information is presented in a way that is easily accessible to lay readers and beginners. And indeed, there is a lot of good information. Aside from merely explaining the physical properties of the Earth, the book discusses some of the ingenious experiments that were done to come to those conclusions, along with some of the commercial applications of geophysical methods and technologies, preventing the field of geophysics from being ossified into a purely academic endeavor.

The book manages to coherently explain all these topics without bringing up a single mathematic equation. The info is purely qualitative, and I think that's perfect for a primer. At the end of the book, the author provides a helpful list of further references, which include other books intended for the general audience, as well as textbooks.

When I went back to the geomagnetism book my professor gave me, I was blown away by how quickly I was able to comprehend all the concepts and equations, which I suppose is due to this geophysics introduction giving me a look at the big picture, from which I was able to make the necessary connections and determine the relevance of each equation and bit of information the geomagnetism book brought up.

Definitely a five star introduction.

[Jay A · Rating 3 out of 5]

It is what it is. Parts were informative and pleasant but it needs to be rescoped for its target audience. It's almost a textbook but I don't think it was meant to be.

[Pete · Rating 3 out of 5]

Geophysics : A Very Short Introduction (2018) by William Lowrie introduces the field of Geophysics. Geophysics is the study of the physics of the earth. Lowrie was a professor of Geophysics at ETH in Zurich and has written a well known textbook on geophysics.

Geophysics is really important for understanding earthquakes and for mining exploration. Geophysical inversions, the incredibly precise measurement of changes in gravity, capacitance and the magnetic fields of the earth are an amazing feat of human ingenuity that is of phenomenal utility to humanity.

The book has a chapter on earth’s place in the solar system and the motion of the planet. There is then a chapter on Seismology that also discusses the earth’s internal structure. A chapter on Seismicity and earthquakes follows. Gravity and geodesy are in the next chapter. Lowrie then looks at the heat and energy in the earth. The final full chapter is on the earth’s magnetic field.

The book is pretty dense and throws concept up after concept. It’s hard to follow and remember really. The book faces the dilemma of being a very short introduction to a subject that really needs sophisticated math to really understand and explain.

Geophysics : A Very Short Introduction provides an overview to a highly technical field as best it can.

[Zach · Rating 3 out of 5]

i have discovered that geophysics is fucking complicated

[Emil O. W. Kirkegaard · Rating 4 out of 5]

I learned a lot!

[Aman · Rating 1 out of 5]

Not a single equation in the entire book! That's no way to learn (geo)physics.

[Jay French · Rating 3 out of 5]

Imagine a science textbook that is chock full of math. Now remove all the math, but leave behind a preponderance of term definitions. That is what you get here. I found the onslaught of geophysics terms to overwhelm my listening to this audiobook. Perhaps audio wasn’t the best medium for this type of book. I quickly lost the connections between, for instance, the variety of named waves rippling through the earth at any point in time, or the counterbalancing twisting that the earth experiences. Were I studying this topic, I can see how this presentation might have helped crystalize meaning, but as a more casual observer I wouldn’t recommend it. I did enjoy the breadth of topics covered, including measurements of earthquakes and volcanoes as well as distances in outer space. A quick read provides some familiarity with the terms and the concepts involved in this branch of science and I suspect would help when starting to study this topic. Interesting bit: the author uses as a measurement of the rate at which huge objects are moving in relation to each other (think tectonic plates or the earth and moon) as “about as fast as fingernails grow”. A great analogy.

[Arno Mosikyan · Rating 5 out of 5]

Heat flow varies greatly over the Earth’s surface depending on the local geology and tectonic situation. The estimated average heat flow is 92 mW/m2. Multiplying this value by the Earth’s surface area, which is about 510 million km2, gives a global heat loss of about 47,000 GW (a GW, or gigawatt, is one billion watts). For comparison, the energy production of a large nuclear power plant is about 1 GW.

[Lee · Rating 3 out of 5]

A short, highly technical introduction to geophysics, this reader felt sometimes overwhelmed by the detail packed in such a short punch, but enjoyed learning the basics, which I could comprehend, and picked out some fun facts (heat flow in older rocks is slower than in newer rocks because older rocks have had much longer to cool).

[Gebo · Rating 4 out of 5]

Super informative book. Maybe a little too informative. A reviewer below said it's like a textbook with all the math taken out, but the jargon in tact. I agree 💯. This was like a whole semester of geophysics in one text. Unfortunately, I'm just not that interested in the subject. Otherwise, I might have found this book to be a 5 star. Hard to say, but it was worth the read nonetheless.

[Usfromdk · Rating 5 out of 5]

An excellent introduction to the topic, with high-level yet satisfactorily detailed coverage of many areas of interest.

[W · Rating 2 out of 5]

This book is dense like the earth’s iron core, and my understanding of geophysics is still shallower than the earth’s crust. Geo-lingo abounds.

Some Interesting Facts:

- Much of our understanding of the inner earth comes at the mercy of earthquakes: quakes cause vibrations, we record those vibrations, and thus, we learn about geophysics.

- We map the interior of the earth like an X-Ray by accounting for slight deviations in those vibrations from the global mean (that’s why oil companies like to hire geophysicists)

- Geophysicists have side gigs using their seismometers to detect and track nuclear weapons tests—like so many fields of science, it has a shared history with military tech (another example is how the tools we now use to sense magnetic fields were first designed to track submarines in WWII)

- Tides are not actually due to the “moons gravity pulling on earth”, but rather they are due to the “rotation of the earth-moon pair” around the “barycenter”, and since the earth is also slightly revolving, it’s actually the centrifugal force of the earth, creating a bulge in the tide. (See this GIF: https://images.app.goo.gl/QP36uSDe42x...)

- There is so much we still don’t know about earth, and what we do know relies on an army of highly sensitive scientific equipment…. So just think of how little we must know about Mars, let alone Neptune, Pluto, or Kepler-138… But the advent of satellites and remote sensing is rapidly increasing the amount of data we have.

[Adithya Chimalakonda · Rating 4 out of 5]

I like to think of the earth as a giant spaceship we're thrust upon to roam the cosmos. Since I'm a fan of physics, it's really cool to read and learn how concepts like gravity, thermal core activity, plate tectonics and magnetism from molten metal convection come together to form the spaceship we're so fortunate to zoom around on. How can we make use of these geological phenomena to improve our ride?

It's what I think about when I look out the window of a travelling vehicle, trek through a bit of wilderness, or just go on a stroll through nearby blocks - what's happening around me right now and how did it come to be?

Picked this up as a physical copy in a book store. Would recommend doing this if you ever find it. It's difficult to get through in a single shot, so I was reading and listening to other books while I perused this one.

Certain sections are difficult to digest in one go because they read textbook-like. I don't feel guilty about skimming those :P and you shouldn't either. I assigned more meaning to this book than what's needed, and perhaps the takeaway from this review is that you should try finding a book about concepts that fascinated and enrapture you specifically.

[Lukasz · Rating 5 out of 5]

Świetna książka opisująca aktualny stan wiedzy z dziedziny geofizyki. Dowiedziałem się czym zajmuje się ta multidyscyplinarna dziedzina nauki, jakie ma zastosowanie praktyczne i dlaczego jest ważna. NAjbardziej zainteresowały mnie kwestie związane z trzęsieniami ziemi. Aby lepiej zrozumieć temat musiałbym całość dokładnie przestudiować kilka razy, książkę musiałbym przeczytać conajmnie trzy, cztery razy. Na ogólne zgłębienie tematu wystarczyło jednak przeczytać ją raz.

[Varun · Rating 3 out of 5]

Looks like a casual, informative read with such a slim, novelish looking form but ends up being a really technical textbook that doesn't quite give enough background or fleshed out proofs for me to understand what's going on.

I wish it was just released as a longer textbook honestly because it's more of an actual college textbook feel than a "very short introduction"

[Simona Atanasova · Rating 4 out of 5]

As a person with not a lot of knowledge in that field I found the book useful to learn new things, however, midway it got in a bit too much detail in areas that weren’t really clear to me. Overall I liked it. It is easy to read, but you do need to give time for this.

[Craig · Rating 2 out of 5]

#audible
Short survey of the science; too much time on elementary topics and not enough of the new.

[Hermione pearson · Rating 4 out of 5]

Good but got confusing towards the end