GigaFlood: The Lake Missoula Flood In Northwest Oregon And Southwest Washington, by Rick Thompson
This book is a sort of geological mystery, where the author discusses a massive Pleistocene flood and its effects on the land of the Pacific Northwest. Admittedly, this is not the sort of book everyone will appreciate, but if you like travel ideas for Oregon and Washington , this book has quite a few. Do you want to understand talus flows and the sheer cliffs and waterfalls of the Columbia River gorge as well as the reasons why Portland the surrounding area is fertile soil and why much of Eastern Washington is pretty barren, this book gives the reason why. The book also gives plenty of reasons why the topography of the region looks the way it does, and even explains the course of some of the rivers and streams of the area. The author is considered an authority on the effects of the Lake Missoula floods in the Portcouver area, and this book gives some good reasons as to why that is the case. If you have an interest in the geology of the Pacific Northwest, this is certainly a worthwhile song.
This book is a bit less than 200 pages and manages to cover plenty of material on the Lake Missoula floods. After a foreword, preface, and acknowledgments, the author begins with an introduction about the Lake Missoula flood story, which takes place in Montana and involves a lake that may have repeatedly formed during the Pleistocene ice ages. With that story told, the main part of the book begins with a discussion of the age age (1) and the phenomenon of ice sheets and ice lobes (2). The author then returns to the mechanics of the Lake Missoula floods (3) and how they were discovered by someone who was not believed for decades (4). From this point the author examines the way the floods formed the channeled scablands of eastern Washington (5) and looks at how temporary lakes were formed in various water gaps along the Columbia River (6) through the gorge (7) all the way to Clark County (8). After this the author talks about a variety of aspects like the gravel pits and rock quarries in the area (9) as well as the inundation of water in the Portland area (10) as well as various flood channels in and around Portland (11). The author discusses the large amount of erratic boulders in the Portland area (12) as well as the effect of the floodwaters on the Tualatin, Yamhill, Clackamas, and Willamette valleys (13), before ending with the effects of the floodwaters making a dramatic rush for the exits after the Kalama gap was forced (14) and the effects of the water departing through Portland while depositing its rich soil (15).
While this book is a fairly technical book and is not written with the sort of style that would make it a popular read, this book actually does prompt at least this reader to ponder about matters that are outside of the book’s focus on geology. What is the relationship between geology and other, more human concerns? The same flood that formed the forbidding and sparsely populated landscape of southeastern Washington that was nearly useless for farming also formed the rich valleys of the Willamette and its tributaries that is a rich area for farming and that supports a large population. Also, that same Portland area is filled with erratic boulders that have been ripped far from home and deposited in a different area, which also applies to many of the human flotsam and jetsam that has been deposited far from home in an area that deliberately celebrates its quirkiness and weirdness. Is there a relationship between the rocks that rest where they clearly are not from and the people that do the same thing in the same places? I suppose it is odd for me to ponder such things, but I do.
 See, for example: