Customer Reviews

Supercontinent: Ten Billion Years in the Life of Our Planet

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"Did the Earth move for you?", asks the voice beside you. Well, yes. Because that's what it does. All the time. The continent you live on used to be someplace else, and far away from where it is now. Your home ground has even been part of a greater landmass known as a "supercontinent" - and will be again. Hence, the title of this book. Ted Nield provides us with a fine account of how we came to learn about these movements. He has brought together the years of research tracking where the rocks have been and where they are likely to go. He likens the movement of continents to a dance of landforms - a "Grand Quadrille". A fine synopsis of the history of geology and its compelling figures - scholars who had to project what was known in their time back into a distant past.

Earth has been a busy place for the past four billion years, and it hasn't stopped to rest. We speak of the "firmness of the Earth", but that phrase is a sham. The key figure in this story is the great supercontinent of Pangaea that began breaking up 250 million years ago. Assembled from previous continents that had once joined and also separated, Pangaea's breakup into places we live on today have been traced in exquisite detail. The matching of rocks in places separated by wide seas provided the clues. In fact, as Nield relates, it was the vast Atlantic that bears the responsibility for Pangaea's fracturing to form the basis for the continents we know today. The author explains how the continents have been engaging in a Grand Quadrille and will continue to do so - for another five billion years, at least.

The progenitor of the idea of "drifting continents" was Alfred Wegener. Using maps to show how western Eurasia and Africa matched the east coasts of the Western Hemisphere, Wegener proposed they had once been joined, but had pulled apart. He couldn't provide a mechanism for the movement, and his idea was rejected - most notably by the geologic "establishment" of the United States. Rejection of the proposal was so strong there that one British geologist described it as "regarding the Declaration of Independence as retroactive to the Palaeozoic". Continents formed separately and remained so through time, it was thought.

However, one US dissident, Reginald Daly of Harvard, had been in South Africa, encountering the work of Alexander du Toit, who noted similarities in rocks of the Great Karoo and South America. That discovery, enhanced by some detailed measurements in Greenland, suggested that movement was occurring. It took a war and the hunt for submarines to reveal what prompted continental movement. An Irish geophysicist, John Joly had already postulated the mechanism, heat from radioactive elements deep in the Earth required escape. That venting pushed the softer areas in the Earth's crust around. Sitting atop that stirring material, the continents track the flow patterns of the heat.

In moving, the continents encounter each other, joining, fusing and establishing mighty landmasses that break up again. Nield skilfully describes the mechanisms and the people who have read the rocks to understand how they work. Beyond Pangaea, for example, the author cites the work of Mark McMenamin, who proposes a yet older supercontinent, Rodinia. Rodinia's importance in the history of the Earth is that it was probably the extant landform around which complex life, after over 3 billion years, finally emerged. Nield's skill in presenting all these complex ideas and their significance never wanes throughout the book. He's achieved a fine summary of the history of modern geology, supported by a collection of portraits and some line drawings. The emphasis on Pangaea is slightly overdone, but his pointer to Chris Scotese's web page of geologic ages more than overcomes that small limitation. An excellent overview. [stephen a. haines - Ottawa, Canada]

Ted Nield's book Supercontinent was very interesting, and I am glad I tackled it. However, it was not entirely what I expected. At least half the book delves back into the history of "lost continents," including Madame Blavatsky with her Lemuria, and James Churchward with his Mu. These were both bogus prehistoric continents put together by erstwhile self-styled prophets. Neither had any scientific underpinning. This seemed out of place in a science book.

Nield also spends several chapters going back to retrace the development of the continental drift theory, and includes a lot of biographical information. I could have dispensed with this.

There are some pluses to the book. For one thing, Nield writes very well. Chapters devoted exclusively to the supercontinent cycle from a scientific perspective are very interesting and worthwhile. Moreover, the book is new, just having been released in 2007. Lastly, the introduction and last chapter are both excellent essays on the benefits and promise of science, and deserve to be read even if nothing else.

My final viewpoint is -- the book is an excellent place to skip around. Read a chapter carefully, skim some material, read another chapter, skip some things, and so on. This is because the topic "supercontinent" is used by Nield as a kind of peg to hang things on. Much of it is scientific, some of it is just "odds and ends." For instance, what Madame Blavatsky and James Churchward have to do with anything scientific is beyond me.

All in all, a mixed bag.

A great resource for the geological history of the planet for the interested amateur. Nield explains in easy to understand terms and analogies the complicated science that allows us today to "travel" back over 4 billion years and witness the development (and redevelopment) of the earth. He also subtly points out the difference between science and myth and why humanity must embrace reality and abandon myths that do not reflect the reality of our situation here on Earth today. He appeals for us to be reasonable and abandon our arrogance and ignorance! Powerful, educational, and ever more important in a world being pushed closer and closer to the brink (for us, the earth will abide...)

This book tackles the great subject of the geologic history of the Earth from the vantage point of plate tectonics. Along the way, the author writes compellingly of the origins and development of life and the history of our atmosphere. He also gets side-tracked in biographies of some key geologists in the Continental Drift controversy as well as a light-hearted discussion of fictitious 'Lost Continents'. Luckily the book is organized in such a way that these digressions can be skipped if desired. My main objection in this book is the lack of good and relevent illustrations and maps. At the very least, a detailed stratigraphic chart relating geologic periods to continent-building and other events would be helpful. Also, maps detailing the assembly and disassembly of the supercontinents would greatly enhance his narrative of these events.

In many ways this is a wonderful and informative work. Paradoxically, it is not an easy read in the most interesting sections but it is well worth the effort.

Each of us gets our three score and ten years, more or less, and as good as such a spell might be, it does not prepare us for seeing the longer picture of the past. We are used to changes in the weather, and we might even be used to earthquakes which are signs that the continents themselves are changing, but continental change comes far too slowly for us to appreciate first hand. Scientists have gradually come to understand how old the Earth is, and how active the continents are, once you take a view of hundreds of millions of years. In fact, instead of the continents we now know, 250 million years ago there was but one continent, a supercontinent called Pangaea. _Supercontinent: Ten Billion Years in the Life of Our Planet_ (Harvard University Press) is not, however, just about Pangaea. Author Ted Nield, the editor of _Geoscientist_, shows that although all of us may now be sitting upon "no more than Pangaea's smashed remains, the fragments of the dinner plate that dropped on the floor," Pangaea was only one in a series of supercontinents, as the land masses careened around the globe, coalesced, and split up again. They are doing the same thing now. Come back in another 250 million years, and there will again be a supercontinent (named by some "Novopangaea"). It's all dizzying, taking in this long view of things; the world is a particularly strange place in the billion year scale. Nield, however, skillfully describes the changes and relates them to our own world, and takes a good deal of the confusion out of a huge mass of data and extrapolations from it.

One of the greatest problems of understanding how the continents shifted was the problem of coming to an understanding of how old the Earth is. Archbishop Ussher's adding up of the "begats" from the Old Testament to find that creation began on 23 October 4004 BC is scientifically ludicrous, but Nield gives it surprising respect as "a serious scholarly attempt, according to the beliefs of his time." Subsequent attempts, in the nineteenth century, centered on looking at how long it would take strata to be laid down or the molten earth to cool, and showed an age of millions of years. Alfred Wegener showed not only that the outlines of the Americas and of Africa and Europe on either side of the Atlantic looked a bit like separated puzzle pieces, but that also there were correlations of rocks and fossils to show that they were originally unseparated. There was enormous resistance to this idea, more from American scientists than European. Wegener died in 1930, his ideas still not adopted by a majority of geologists; now, however, they are the fundament on which geology bases its explanation of continental movement. Nield calls the supercontinent cycle "the grandest of all the patterns in nature", since each cycle takes so many millions of years and since the continents moving around affect all geology, ocean patterns, weather, and the development of life itself. The cycle not only explains the ancient history of our planet, but has to be the foundation for our understanding immediate phenomena like earthquakes. The supercontinent cycle is a new idea, and we are only just beginning to understand it.

Nield presents the idea that science, too, is like a supercontinent, able to reconstruct the distant past and also able (if politics allows) to save thousands of lives in the next tsunami. He says that understanding the evolution of the Earth's atmosphere in the Precambrian age "helps us understand the massive, uncontrolled climate experiment in which the human race is currently engaged." He reminds us that denying one part of science is to deny all the other parts within the scientific whole that are connected to the part denied. His last pages, therefore, address the "young-Earth creationists", who use what they call "creation science" (and which Nield calls a "non-subject") to bolster their claims for an Earth no older than Ussher said it was. Science may not be able to guarantee absolute knowledge, but the likelihood that the Earth is not billions of years old is nil, and there is evidence to counter any reasonable doubt to the contrary. The key word, Nield reminds us, is "reasonable": "Nothing ever remains beyond unreasonable doubt." The way evidence is gathered and scientific explanations are made over the centuries is wonderfully described here, as is the discovery of deep time, a huge and important idea that puts us in our place in the cosmos.

In this remarkable book, the author touches upon just about everything regarding long lost continents: how the idea of a supercontinent came about, ancient and not-so-ancient myths (Atlantis, Lemuria, Mu), why continents cannot simply sink, highlights in the lives of some of the individuals involved and, in particular, the fascinating science. After discussing how the existing continents are moving relative to each other (continental drift) and how they will likely collide in the distant future, thus forming another supercontinent, he discuses the supercontinents of the past. In so doing, the reader is treated to a history of the earth and how it works, brimming throughout with scientific facts, principles as well as theories and the evidence that supports them. The scientific processes involved and the dating techniques that are used by scientists are particularly well explained; this is not surprising given the author's credentials. The writing style is clear, elegant, authoritative, often witty and always quite engaging. As a result, this is a book that can be enjoyed by anyone, although science/geology buffs may be the ones that would savor it the most.

Ted Nield does an excellent job of bringing a rather esoteric topic in geology to life. He discusses the geologically slow process of continental breakup and coalescence in the light of major events in the history of life: The end Permian mega extinction when Pangaea existed, for example, and the beginnings of complex life that roughly coincided with with the existence of the prior supercontinent, Rodinia. He highlights the careers of the various scientists who unraveled these geological stories and nicely fleshes out the complexities of how the validity of scientific truths usually overcome short term politics and animosities. He likens science-derived discoveries to a kind of Supercontinent of knowledge that allows human beings to reconstruct both lost and future worlds that we will never see directly. The fruits of this rather abstract knowledge, however, results in real benefits to people today--like earthquake warning networks that alert hundreds of thousands of people to tsunami dangers along the Ring of Fire.

Although I'm pretty well read in paleontology and geology, I found Nield's treatment of this topic accurate and fresh. I also learned more about certain scientists--John Joly, in particular--that will lead me to further reading.

I won't repeat the many accolades for the book. It was a good adjunct to my understanding of present-day tectonics. I studied geology in the early 60's where a professor gave me hell for a paper on "continental drift", which he didn't believe in. I would give it 5 stars for content. It kept my interest continually, but how a geologist, especially, can write a book with such a dearth of maps is beyond me. I found myself having to go to the internet and other books over and over to look for relevant maps, and the reader shouldn't have to do that!

Based on the subtitle of this book, I was expecting details on the changes in the earth's crust/continents over the last 10 billion years -- a very interesting survey that would be! However, the author begins with a parable on what an alien visitor would see from outer space, suitable for teenage readers, after which the bulk of the book is a survey of the history of plate tectonics. This survey focuses on the individuals involved, jumping back and forth between them, and offers little real information. It is not particularly scientific but would instead be a history of the research, with bios of the scientists/philosophers. I ended up skimming in order to find the kind of info I was looking for. Also, to note, the illustrations don't have captions, so you aren't entirely sure what you are looking at or where/why it applies to the text.

This geologic history was much more about the characters involved than I expected. There was a good discussion of the actual physicalities that occurred, but the in-depth discussion of the geologists seemed to interrupt the flow of the book. It was still worth the read, though. David Stewart