As some of you may know, a controversy regarding the sale of a certain book at Grand Canyon National Park has existed on and off for the last few years. The controversy was re-ignited on December 28th, 2006, when a group called PEER (Public Employees for Environmental Responsibility) issued a press release from their headquarters in Washington D.C. Many "facts" were wrong in this press release and although they denied this for a number weeks, they finally retracted many of their most egregious errors. The group has publicly apologized for getting their story wrong. However, the details of the controversy are interesting to explore.
The book is entitled, "Grand Canyon - A Different View" - a very apt title indeed! In it, author Tom Vail and other creationists explain how, within a ONE YEAR TIME PERIOD, all of the strata of the Colorado Plateau were deposited, half of it completely eroded away, and the entire Grand Canyon was cut in addition to that! Again, all in ONE YEAR. Of course, this is not really possible given the evidence at hand but creationists believe this by starting with a conclusion (there was a Biblical flood) and then look for the small bits of evidence on the landscape that might prove it's true (the Grand Canyon had to be cut by this flood). This is not science. It never has been and never will be. However, the question presents itself - do only science-based books need be sold at Grand Canyon? Within the book stores at the canyon, other Native American "creation legends" are sold and placed within the inspirational section of those book stores large enough to have themed sections. And that is where Tom Vail's book is sold. Some vocal scientists have decried the presence of this book at Grand Canyon. I do not.
Now I do not subscribe to a creationist view of the earth. I am a tried and true geologist and the evidence seems overwhelming to me that a geologic origin is responsible for the magnitude of earthly beauty we see before us. However, I do believe that the creationist controversy has been fueled in part, by some scientists desire to completely ignore, stifle, and dare I say, censor (?) the creationist view. All under the mistaken premise that if we engage creationists we somehow validate their view of earth history. This possibly wrong assumption has allowed creationist a "free pass" so to speak and they have seized on the "non-debate" and have gotten their message out quite effectively. All without any follow-up by scientists.
I believe that as scientists we are educators by default. Science suffers today because it is not valued by society proportionate to its rewards. For this reason, we must engage the public at every opportunity to inform them of the beauty and magic of science. Tom Vail's book is harmless with respect to it's presence on the shelves at Grand Canyon book stores. It is not a big seller and it is placed well away from the 20 or so other great geology books available at the canyon. Yet some scientists yell and scream that this caters to creationism - without taking the time to fully understand how creationists got so powerful in the first place.
I believe that this "controversy" provides an excellent way to engage the larger public in a discussion about what exactly is creationism, or science for that matter. Viewed in such a way, people can look at the evidence for themselves and decide which story holds up to close scrutiny. Do geologists really believe that their story won't hold up against creationism. Of course not - but they behave as if it would. The idea is not so much to win everyone over to "our side" but to begin a discussion where ideas can be presented and made to stand on their inherent strengths or fall on their weaknesses. True, we cannot debate science vs. faith but we can respond intelligently to an audience that wants very much to hear our side. Censorship is not the answer. Ironically, sales of Tom Vail's book generates income for the non-profit Grand Canyon Association, which turns it's income over to the park to fund many worthwhile science projects within the canyon.
For a real geologic view of how the Grand Canyon formed, look at my book, "Carving Grand Canyon". It is a bestseller at the park (10,000 copies sold in just 20 months). It has won numerous awards including a National Outdoor Book Award - 2006. It engages readers to look critically at the evidence and doesn't attempt to stifle discussion with those who hold other views. The answer to this controversy is not to back away from creationists but to engage them! Certainly the status quo thus far has done nothing to quiet the other side.
Thursday, February 15, 2007
Wednesday, November 16, 2005
Jewels of the Indian Ocean
A Visit to a Remote Hot Spot on Planet Earth- Reunion Island.
Talk about remote! La Reunion is just about the anti-pode of Flagstaff, Arizona. I visited there November 1 to 3, 2005 on a Private Jet Trip called "Jewels of the Indian Ocean". Rising 10,000 feet out of the sea, the volcano is an additional 11,000 feet below sea level. After taking a spectacular helicopter ride over the active part of the island, we landed in a "cirque" near the little town of Cilous. These cirques are spectacular features and the small group who hiked with me heard about my initial musings on their formation.
I first pointed out to our small group to notice the volcanic layering that could be seen in the walls of rock around Cilous. It is always better to begin geology talks with something that everyone can see because eventually geologists must talk about things that can only be envisioned from the past. The layering of rocks leads to the story of how the island grew by successive eruptions of lava. I then mentioned that Reunion is a mountain that is over 6000 meters high if you include the underwater portions of the volcano that are not visible to us.
The next thing to discuss was how the volcano behaved through time. Beneath the vent, a large magma chamber exists and this is where the lava originates. As eruptions to the surface proceed, the magma chamber becomes emptied and a void is created within the earth directly below the volcano summit. This can cause the top of the volcano to collapse creating a caldera. I then talked about the importance of caldera forming events from many well-known volcanos around the world.
However, the cirques on Reunion have a particular shape to them that suggests that they are not just simply calderas. It looked to me as if groundwater processes were very active in shaping the cirques. It was important to say "shaping" the cirques rather than "creating" them because they may have originated as smaller collapse calderas, that were subsequently enlarged and reshaped by the later groundwater processes. These groundwater processes may include a process known as sapping, whereby water running out from between the layers of lava, undercuts overlying layers. These overhung layers then collapse and the collapsing proceeds up to the top. This semi-circular shape to the cirques looks a lot like sapping has been at work. I refered back to the present climate of Reunion. we heard that this was the place where in March, 1952, a single 24 hour rain storm left 73 inches of rain! With its abundant rainfall, there is lots of groundwater that could run out of the ground starting the sapping process. It's nice to include other topics in geology talks, like climate, weather, and people.
Seeing Weird Limestone Features in Rural Madagascar - Tsingy
I will give you a few words geologically about the tsingy in Madagascar. In other parts of the world this type of erosion is known as karst. That is a region in the old country of Yugoslavia that also has a lot of limestone terrain and the name of that region gives the name to the feature. Karst or tsingy can only form in areas where the limestone is very pure without interbeds of shale or sandstone. The purity of the limestone will allow it to erode this way - if there was shale or sandstone within the limestone, the pillars would not form. Limestone is soluble in rain water, which means that it gets eaten away chemically by water. When rain falls on this limestone, the water reacts with the limestone and creates a weak acid called carbonic acid. This acid water sits in subtle depressions on the rock surface and eats away at it. This causes the depression to become deeper through time. In Madagascar, this vertical deepening is extreme and if you look at the tsingy closely, you'll notice that the pillars of limestone are just those areas in between vertical depressions. I noticed on our boat beach that some of the tsingy pillars had holes in their bases - that would be were the acidic waters ate through connecting two depressions.
The mushroom shaped tsingy on a boat trip we took were formed on their top surfaces the same way as above but the skinny base was formed along the tide line in a different manner. The salt water from the sea played an important role in forming these pedestals. When salt water creeps into the limestone at water line, it grows salt crystals inside the rock. As these salt crystals grow, they physically pry apart the rock components, eroding them much faster in this horizontal zone where the salt water seeps in. That is how the mushroom shaped rocks formed. A trip to Madagascar is amazing!
Talk about remote! La Reunion is just about the anti-pode of Flagstaff, Arizona. I visited there November 1 to 3, 2005 on a Private Jet Trip called "Jewels of the Indian Ocean". Rising 10,000 feet out of the sea, the volcano is an additional 11,000 feet below sea level. After taking a spectacular helicopter ride over the active part of the island, we landed in a "cirque" near the little town of Cilous. These cirques are spectacular features and the small group who hiked with me heard about my initial musings on their formation.
I first pointed out to our small group to notice the volcanic layering that could be seen in the walls of rock around Cilous. It is always better to begin geology talks with something that everyone can see because eventually geologists must talk about things that can only be envisioned from the past. The layering of rocks leads to the story of how the island grew by successive eruptions of lava. I then mentioned that Reunion is a mountain that is over 6000 meters high if you include the underwater portions of the volcano that are not visible to us.
The next thing to discuss was how the volcano behaved through time. Beneath the vent, a large magma chamber exists and this is where the lava originates. As eruptions to the surface proceed, the magma chamber becomes emptied and a void is created within the earth directly below the volcano summit. This can cause the top of the volcano to collapse creating a caldera. I then talked about the importance of caldera forming events from many well-known volcanos around the world.
However, the cirques on Reunion have a particular shape to them that suggests that they are not just simply calderas. It looked to me as if groundwater processes were very active in shaping the cirques. It was important to say "shaping" the cirques rather than "creating" them because they may have originated as smaller collapse calderas, that were subsequently enlarged and reshaped by the later groundwater processes. These groundwater processes may include a process known as sapping, whereby water running out from between the layers of lava, undercuts overlying layers. These overhung layers then collapse and the collapsing proceeds up to the top. This semi-circular shape to the cirques looks a lot like sapping has been at work. I refered back to the present climate of Reunion. we heard that this was the place where in March, 1952, a single 24 hour rain storm left 73 inches of rain! With its abundant rainfall, there is lots of groundwater that could run out of the ground starting the sapping process. It's nice to include other topics in geology talks, like climate, weather, and people.
Seeing Weird Limestone Features in Rural Madagascar - Tsingy
I will give you a few words geologically about the tsingy in Madagascar. In other parts of the world this type of erosion is known as karst. That is a region in the old country of Yugoslavia that also has a lot of limestone terrain and the name of that region gives the name to the feature. Karst or tsingy can only form in areas where the limestone is very pure without interbeds of shale or sandstone. The purity of the limestone will allow it to erode this way - if there was shale or sandstone within the limestone, the pillars would not form. Limestone is soluble in rain water, which means that it gets eaten away chemically by water. When rain falls on this limestone, the water reacts with the limestone and creates a weak acid called carbonic acid. This acid water sits in subtle depressions on the rock surface and eats away at it. This causes the depression to become deeper through time. In Madagascar, this vertical deepening is extreme and if you look at the tsingy closely, you'll notice that the pillars of limestone are just those areas in between vertical depressions. I noticed on our boat beach that some of the tsingy pillars had holes in their bases - that would be were the acidic waters ate through connecting two depressions.
The mushroom shaped tsingy on a boat trip we took were formed on their top surfaces the same way as above but the skinny base was formed along the tide line in a different manner. The salt water from the sea played an important role in forming these pedestals. When salt water creeps into the limestone at water line, it grows salt crystals inside the rock. As these salt crystals grow, they physically pry apart the rock components, eroding them much faster in this horizontal zone where the salt water seeps in. That is how the mushroom shaped rocks formed. A trip to Madagascar is amazing!
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