This enjoyable book offers “a new geological history of North America,” summarizing a vast swath of research from many disciplines to expound on the continent’s evolution over deep time. The geographic scope is a little inconsistent – it mainly centers on the Lower 48 United States, but includes bits of Canada and a brief foray into Mexico for the Chicxulub impact crater, but also mentions Hawaii (which though part of the U.S. isn’t part of the continent) while almost entirely ignoring Alaska. But for the areas it focuses on as relevant to telling the story of the continent, it delves into great, highly-specific detail: the kind of detail that appeals greatly to a geoscience outreach nut like me. Specific waterfalls in state parks, specific exit numbers to reach key outcrops, this glacier has retreated by that many miles, and so forth — all this is evidence of a willingness to luxuriate in the level of geographic detail that might put a novice off, but suggests to me that Dvorak really knows what he’s talking about. Then again, there were some errors that seemed preventable: placing India in the northern hemisphere at the time of the Deccan Traps’ eruption, mistakenly referring to the Coastal Plain as “the Piedmont,” indicating that Mt. Moran’s 800 Ma mafic dike was intruded “near the end of the Paleozoic.” Maybe these are pretty minor in the grand scheme of things – the book is PACKED with details, and it’s probably inevitable a few of them might not be exactly on target. I found much to appreciate in How The Mountains Grew: new fossils to check out, new parks to put on my “must visit” list, new perspectives on large scale teleconnections between disparate phenomena. I’d never heard of Dvorak’s writing prior to seeing this volume pop up in a “related books” algorithm on AbeBooks.com, and I’m so glad it did. Turns out he has three other titles, which I just ordered — and look forward to reporting on them to you here someday!