What geological concept or idea did you hear about that you had no notion of before (and likely surprised you in some way).
This was a hard one for me, because I feel like there is so many things that could be written about and it's hard to narrow it down to just one. Finally I came up with this one.
THE ALVAREZ HYPOTHESIS Here (Wikipedia)
When I was in undergraduate school, the department I was in was very small. Because it was so small the professors there encouraged us to go to conferences, intercollegiate field trips and listen to guest speakers at other nearby universities - where the department had some arrangements where we could get in, since they couldn't bring the speaker to our department due to budget constraints.
When I was very new in the department some of the more senior students had gone to a conference in Toronto, Canada. They came back and the few of us who didn't go were very curious about the conference - and were asking a ton of questions about it. One of my friends was telling us all about it and that J.Tuzo Wilson was the speaker that got most of the attention with his theories about plate tectonics. I couldn't believe it when one of my very old professors (he got his degrees before WWII) in the department said that J.Tuzo Wilson's (here) stuff was a 'bunch of bunk', and his theories would not hold up with the test of time. (At that time '74, Wilson's theories were mostly known through his articles and he was mentioned in very few text books.) I was absolutely shocked by this attitude of that one professor, because what little I had read of Wilson's theories seemed very believable to me. I felt like this professor was the one who was wrong. I lost a lot of respect for him with that one comment, and started to question what he was teaching me in his classes. This professor had stagnated in his mind set by only accepting what he was first taught and not expanding his mind to other ideas that have developed with advent of other technologies.
After that discussion, I told myself I should always keep an open mind and not limit my thinking like that professor had done with Wilson's theories.
So a few years later, I went to visit another university to hear this guy present his research. (I wish I could recall his name but it has totally faded from my memory and also the title of his speech.) At first he was pretty charismatic and came across as being very believable. He had done a lot of research on the Cretaceous -Tertiary (K-T)(Mesozoic/ Cenozoic) boundary. He theorized that some catalytic event had occurred, which caused the dinosaurs and other animals to have a mass extinction. The mass extinctions had been well documented for quite awhile, but what set his ideas apart was he was claiming that the extinction was due to a single event and not a gradual demise of the animals as it was then believed to have happened. He pointed out how all across the world there was this dust layer with a radiation marker in it that could be traced which always was associated with the end of the period. He had traveled to (or gotten) different places in the world collecting samples and then analyzing that layer. He concluded that it had all come about from a single event, that caused the greenhouse effect which lead to the mass extinction.
Up to this point everything seemed very believable and done scientifically and thus deserved our consideration. This was something that was totally new to me and surprised me. I was excited about the implications of what he was saying.
But then he lost the audience as he told us his hypothesis as to what the event was that cause this dust layer. What he then said caused so much commotion in the auditorium, I had never seen anything like that before or after. All these educated people then put him through one of the most grueling times I had ever seen anyone endure to defend his hypothesis.
His hypothesis was that the dinosaurs had a nuclear war, and that was why there was this radiation associated with this layer. He then went on and named Tyrannosaurus Rex as the perpetrators of this event. He compared the brain size of a human and the T Rexes and pointed out how much bigger T Rexes were than humans and thus they must have had more mental capacity than man. He had some other data to back up his ideas but this is what stuck with me all these years.
The man defended himself well but when he was done most of the people there dismissed everything he had to say as the old professor put it as 'bunk', because his hypothesis was so hard to accept. Some of the comments I heard as I was leaving was he had been watching too much Star Trek or read too many science fiction books or had too much of an active imagination, etc. What got to me was how they treated everything he had to say as wrong and didn't give him the benefit of the doubt for any of it being true. I must admit I went along with the crowd, and thought it all crazy stuff too, but I also reminded myself I should keep an open mind. I didn't even consider that there might be another more reasonable explanation to muse upon.
I kept on thinking about this speaker and how he defended him self. One of his very last comments was 'If man were to have a nuclear war today, how would the intelligent life 65 million years from now know that man was just as intelligent and that he was able to develop devices that could destroy the world. Wouldn't everything he had created be destroyed either by the war or by the natural processes that were sure to have occurred since then. What evidence would there be to prove man was intelligent and that he was capable of causing so much destruction?' I never heard of the guy again or of his theory and basically let it drop for my mind.
Then around 1982, I saw an article about the Alvarez hypothesis. The Alvarez's were basically presenting the same type of results from their data that the first guy had obtained years before. They too concluded that the K-T boundary was due to a single event only their hypothesis as to why this dust layer occurred was totally different. The Alvarez's believed it was due to a meteorite hitting the earth.
In my mind I compared the two. I could accept the Alvarez's hypothesis, while I couldn't the other guy. I felt sorry for the first guy. The first guy had had very legitimate data yet he failed to connect the points properly. No one took him seriously and all of his stuff was dismissed as wrong. As far as I can tell his material was never published. Instead of getting recognized for the work he did do-- he is now forgotten. While the Alvarez's presented something that the geologic community could accept, and they are now recognized for it thus getting all the credit for it.
The point this guy failed to realize was the iridium discovered in association with this dust is associated with asteroids. A point that would have been easily missed since that connection wasn't widely established at that time. I guess it surprised me that the 1st guy didn't consider the possibility of a meteorite impact and present that too. In fact it surprised me that none of us even brought that up as a possible explanation to ask him if he had considered that when we were grilling him.
(It did make me realize that I shouldn't fall in love with just one idea and that I should pursue as many different ideas as possible when analyzing things.)
When I read the article by the Alvarez's, I was working as a geologist with a major oil company in the Gulf coast region. At the time I was amazed that there were successful wells being drilled in areas that most of the industry had dismissed as being unproductive. I felt these operators had some bit of information or technology that gave them some insight that the rest of us was missing. I felt like I needed to come up with something along those lines too so that I could have an advantage over others.
I felt this article might just might be it for me. It was something I could sink my teeth into and work with. I wondered just how many people would make the connection to a single meteorite event causing the the Cretaceous Tertiary boundary. To most of them the K-T boundary was just a geologic time thing where there was mass extinctions with no connection to the gulf coast except in the naming and dating of the formations.
I realized that iridium layer could be something that could be mapped and followed around the gulf area. Any place that had this sediment should then be able to be mapped. I figured it could have a characteristic mark on the well logs and maybe even with the seismic data. I gathered from what the Alvarez's wrote, that meteorite would have shaken up the whole world. In the gulf area, there were already a lot of normal faults associated with the forming of the basin (going back to J. Tuzo Wilson ideas, which were then widely accepted and used to interpret the formation of the gulf.). The impact of the meteorite and the resultant shaking of the world could have caused some of those normal faults to shift again. The shaking could also cause the oil and gas to migrate. Traps may have been formed where there hadn't been traps before. The possibilities seem so exciting with what I could do with this line of thought.
I tried to present my idea to my boss so I could work on it more. I was reminded that I was a developmental geologist and I should stick to that- the idea was dismissed as bunk. It wasn't even passed on to the explorations geologists in the company. When I was done with that meeting I knew what that first guy must have felt like at the time. I felt like I was onto something then and was frustrated because I couldn't convince others of its merit. I let the idea drop and never followed up with it because there was so many other things to work on at the time. We were mainly trying to figure out why a zone was as prolific as it was when the electric logs indicated it should not be productive or barely produce anything at all. Since we couldn't rely on the standard interpretations we needed also figure out the extent of the field, which also taught me a very valuable lesson that things don't always happen to be the way you think it should be.... and to always keep your mind open to new ideas.
Since then I've like seeing the work that has been done with the Alvarez hypothesis. When years later they discovered the Chicxulub crater in the Yucatan peninsula and I heard about it, I felt my thoughts about this hypothesis would be even more relevant to the oil and gas industry than I had previously thought. Unfortunately by then I was out of the industry and into a totally different line of work so I've never had the chance to pass it on to anyone until now. I just wonder who else has thought like me along those lines?
HERE'S SOMETHING TO MUSE UPON -Even though I prefer Alvarez hypothesis and accept it, I keep on thinking back to the the first guy and sometimes wonder what if the first guy is right and the Alvarez hypothesis is wrong. Just a thought.
Below is what Wikipedia has to say about that theory and impact meteor with regards to the K-T boundary.
Impact Event
The K–T boundary exposure in Trinidad Lake State Park, in the Raton Basin of Colorado, shows an abrupt change from dark- to light-colored rock.
White line added to mark the transition.
Such an impact would have inhibited photosynthesis by generating a dust cloud, which would block sunlight for a year or less, and by injecting sulfuric acid aerosols into the stratosphere, which would reduce sunlight reaching the Earth's surface by 10–20%. It would take at least ten years for those aerosols to dissipate, which would account for the extinction of plants and phytoplankton, and of organisms dependent on them (including predatory animals as well as herbivores). Small creatures whose food chains were based on detritus would have a reasonable chance of survival.[58][69] The consequences of reentry of ejecta into Earth's atmosphere would include a brief (hours long) but intense pulse of infrared radiation, killing exposed organisms.[37] Global firestorms may have resulted from the heat pulse and the fall back to Earth of incendiary fragments from the blast. High O2 levels during the late Cretaceous would have supported intense combustion. The level of atmospheric O2 plummeted in the early Tertiary Period. If widespread fires occurred, they would have increased the CO2 content of the atmosphere and caused a temporary greenhouse effect once the dust cloud settled, and this would have exterminated the most vulnerable organisms that survived the period immediately after the impact.[74]
The impact may also have produced acid rain, depending on what type of rock the asteroid struck. However, recent research suggests this effect was relatively minor, lasting for approximately 12 years.[69] The acidity was neutralized by the environment, and the survival of animals vulnerable to acid rain effects (such as frogs) indicate this was not a major contributor to extinction. Impact theories can only explain very rapid extinctions, since the dust clouds and possible sulfuric aerosols would wash out of the atmosphere in a fairly short time—possibly under ten years.[75]
Subsequent research identified the Chicxulub Crater buried under Chicxulub on the coast of Yucatán, Mexico as the impact crater which matched the Alvarez hypothesis dating. Identified in 1990 based on the work of Glen Penfield done in 1978, this crater is oval, with an average diameter of about 180 kilometers (112 mi), about the size calculated by the Alvarez team.[76] The shape and location of the crater indicate further causes of devastation in addition to the dust cloud. The asteroid landed in the ocean and would have caused megatsunamis, for which evidence has been found in several locations in the Caribbean and eastern United States—marine sand in locations which were then inland, and vegetation debris and terrestrial rocks in marine sediments dated to the time of the impact. The asteroid landed in a bed of gypsum (calcium sulfate), which would have produced a vast sulfur dioxide aerosol. This would have further reduced the sunlight reaching the Earth's surface and then precipitated as acid rain, killing vegetation, plankton and organisms which build shells from calcium carbonate (coccolithophores and molluscs). In February 2008, a team of researchers used seismic images of the crater to determine that the impactor landed in deeper water than was previously assumed. They argued that this would have resulted in increased sulfate aerosols in the atmosphere, which could have made the impact deadlier by altering climate and by generating acid rain.[77]
Most paleontologists now agree that an asteroid did hit the Earth about 65 Ma ago, but there is an ongoing dispute whether the impact was the sole cause of the extinctions.[23][78] There is evidence that there was an interval of about 300 ka from the impact to the mass extinction.[79] In 1997, paleontologist Sankar Chatterjee drew attention to the proposed and much larger 600 km (373 mi) Shiva crater and the possibility of a multiple-impact scenario.
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