Observations of Washington State Landscapes, Geology, Geography, Ecology, History and Land Use
Friday, July 15, 2011
Cascadia's Fault - by Jerry Thompson
I have been meaning for some time to do a write up on Jerry Thompson's Cascadia's Fault. The Cascadia Fault is the great subduction zone fault line that extends from off of Cape Mendicino on the northern California coast to well up the coast of Vancouver Island in British Columbia Canada.
The challenge of reviewing this book is trying to do the book proper justice. I am not sure I can meet the same standard of good writing, good journalism and good science that Mr. Thompson did so well.
I am a geologist; I am way into tectonics; I even made what I would describe as a pilgrimage to see the ghost forest at the Copalis River that was part of the compelling body of evidence that built the case for a great quake on the coast of Washington HERE . As such, some of this book provided the simple pleasure of reading a very well written perspective on the familiar; however, Cascadia's Fault included ideas and stories and perspectives on the subject that were new to me.
Mr. Thompson states in the introduction of the book that "Scientists, civil engineers, and emergency planners know with certainty that it's bound to happen here (a huge quake along the coast), but they're having a devil of a time getting anyone to pay attention. This book I hope will change that". I hope this book will too.
The book tells the story of how geologists unraveled the clues about the great quake. It is a great story of how science gets done and how observations and ideas build on one another. I remember the debates about whether or not the Cascadia subduction zone was asiesmic or locked and dangerous and how that question was resolved. But the book adds many facets of the story I did not know and puts into context the early days of plate tectonics figuring out seismicity along subduction zone faults and how those early day ideas evolved how we think about the Cascadia fault. The book reads like a very good mystery novel building the clues one on another, but without the typical overblown hype that often passes as science writing. And there are tid bits of information that were fun to read about. Like Brian Atwater missing the ghost forest at the Copalis River on his first trip there. One on my favorite's was a discussion about turbidite deposits in sediment cores sampled along the Pacific Northwest coast in the late 1960s. Turbidites are essentially underwater landslide deposits and the sampling had found the same number of tubidite deposits at every site. A student assistant on the project suggested "Hey, maybe it could be earthquakes!" This brilliant idea was initially dismissed as too unbelievable, but clearly the idea did not go away and turned out to be true.
If there is hype or drama in the book it comes in the matter of fact descriptions of past disasters such as the tsunami that rolled into Port Alberni on the west coast of Vancouver Island or the chaos of a tsunami evacuation from Long Beach, Washington or the stories told by First Nations peoples along the coast that were not paid the heed they deserved. I have read these First Nation accounts of the 1700 event before and have seen fire pits covered with tsunami deposits. The stories are compelling and one has to wonder if our history in the northwest may have turned out a bit different if shortly before European arrival to the area the quake had not happened.
I very much appreciated, the book's treatment of earthquake prediction - a straight forward assessment that ultimately backs the idea that preparation is of utmost importance. And it was great to read about the work that went into creating the remarkable tsunami models that have saved thousands of lives and should be utilized for not just local planning but regional planning.
Much of the geology work on Cascadia's Fault is mud and sand exposed in drill cores and in pits. Papers are written in scientific journals or technical reports for building designs or geology chapters in land use or permit plans. Oregon State University geologist Chris Goldfinger is quoted in the book many times but sums up my own feeling about Cascadia's Fault the last time I was out on Washington State's outer ocean coast. Dr. Goldfinger said "It's a little hard to go to the beach and just hang out there and enjoy it." Gary Rogers at the Geological Survey of Canada states that "Sumatra is Cascadia."
In his years of covering this story, Mr. Thompson has gained an insight into Cascadia's Fault that is well worth taking the time to read. This book tells a compelling scientific story of discovery. But the book goes beyond the science and presents the case for society preparing for an event we are at this point are ill prepared for. Mr. Thompson's Cascadia's Fault takes the subject from the occasional quotes from geologists and presents a compelling case for regional and national planning that this pending event requires.
The people of Port Alberni know what to expect. They did not wait for expensive studies funded by the federal government to draw lines of hazard on the map for their planning. Mr. Thompson hopes that people will start to pay attention and began to prepare. He has done his part. This book should be required reading for every emergency planner, every land use planner and every politician in our region. And we should insist as a society that we are prepared for this event like no other our nations' have experienced.
Dan McShane is an engineering geologist with Stratum Group, a geology and environmental consulting company based in Bellingham, Washington. Dan has been reading Washington State landscapes since driving across the Horse Heaven Hills with his father and brother in 1970. Dan's wife has started painting Washington landscapes. The intent of this blog is to help all Washington travelers better understand the landscapes we see and share field observations.