Jan Zalasiewicz

Zalasiewicz provides a constantly astonishing account of the development of our planet from the Big Bang to the present and beyond to Earth's final (or final perhaps) dissolution. Told from the retrospect of a Welsh slate pebble, which evolves in parallel with Earth, and indeed with Wales, as we know it. Not the least of the virtues of Zalasiewicz' text is his account of climate change on a cosmological time scale. Planet in a Pebble is a wonderful companion to Zalasiewicz The Earth After Us show more and probably best read before that book. Both require a basic high school knowledge of chemistry, geology and physics. Zalasiewicz writes with engaging eloquence and clarity. show less

Zalasiewicz and Williams try to cover a truly vast subject - the origin, history, present state, and future of Earth's oceans; the possible vanished seas of Venus and Mars; the subsurface water layers of various bodies of the outer solar system; the hydrocarbon lakes of Titan; and the hypothetical water masses of extrasolar planets - in a compact (336pp) and accessible package. They succeed quite well I think: there is, of course, a near infinity of further detail that could have been added, show more but by keeping largely to the big picture the authors provide an excellent introduction to the present state of knowledge about seas on Earth and elsewhere. show less

“Take a pebble. A slate pebble, say, from a beach in Wales. Look at its rich grey, cut by veins of white quartz. Look closely. There are other markings too…”

The Planet in a Pebble is the story of the Earth as determined from a single pebble, from the depth of time and across the far reaches of space to its current existence. The many events in the Earth’s past that can be deciphered from the subject pebble include: the Big-Bang; solar system creation; planet creation; volcanic show more eruptions; magnetic fields, the lives and deaths of extinct organic species; the nature of long-vanished oceans; transformations in the depth of the earth; the creation of fool’s gold and of oil; and tectonics.

Jan Zalasiewicz demonstrates, in an accessible and lyrical manner, how geologists reach deep into the Earth's past by forensic analysis of even the tiniest amounts of mineral matter to discover aspects of Earth’s history. However, while the writing style is entertaining and accessible, there is some technical vocabulary that may be confusing for non-geologists, but this can’t be helped in a book like this. None of this technical vocabulary is incomprehensible with a bit of application of grey matter.

The author shows how many stories are crammed into each and every pebble around us, no matter how ordinary the pebble. But this pebble is also a part of the Earth’s amazing journey through time. show less

If aliens visited the Earth 100,000,000 years from now, long after humanity has passed away, would they be able to detect any signs that we were ever here at all? The answer is yes, but much less than you might think. They'd have to really be looking, and to know exactly what they were doing, and even then, the record would be hard to piece together and would leave an awful lot out. At the very least, they could learn from the geologic record that there was an odd little warming period that show more didn't fit the usual pattern of Earth's warming and cooling cycles, but they might or might not ever understand what caused it.

I find this question, and its possible answers, fascinating. Contemplating this really gives one a sense of the vastness of geologic time, and how fleeting human timescales are in the scheme of things. Thinking about how little will be left of us a hundred millions years from now also brings home just how little we can actually know of the world of a hundred million years ago. How many creatures were alive then that we will never find fossils of at all?

So, the parts of this book that dealt directly with the question in the title were really interesting to me. Unfortunately, there was a lot of the book that didn't. I had the feeling I was in trouble when, skimming over the acknowledgements, I saw the author explain the idea behind it: "to explain the workings of stratigraphy through the future of humankind and the fruits of its industry." That is basically what he does: uses this question as a launching point to talk about geology and the science of how we understand the history of geology, complete with very long explanations of things like exactly how new seafloor is formed. But, I have to say, while I find geology interesting in theory, the details of it quickly get boring to me. What I was hoping for, really, was a book that would explain the fossilized future of humanity via the workings of statigraphy, and not vice versa.

For those who are interested both in pondering the question of the title and getting some detailed lessons on geology, though, it may be more interesting overall. show less