Erosion vs. Weathering

I never really explained why I named this blog what I did, but there is a reason. You see, since I'm an undergraduate student (for only two more semesters) I wanted to tell the story of my journey from lowly and ignorant undergraduate through graduate school and into my own career (however long that takes). However, that only makes sense if you know the actual definition of erosion:

Erosion-The physical removal of rock by an agent such as running water, glacial ice, or wind.

And compare that to weathering:

Weathering- The group of processes that change rock at or near the Earth's surface

Now why do I care about that?  Well besides confusing the two makes it seem like I feel like my education is disappearing or being torn down some how, the real problem is that erosion is used as a literary device by several people and it is almost always used wrong. Here are two examples:

http://www.gosanangelo.com/news/2008/apr/19/halt-us-educational-erosion/

http://chronicle.com/article/Public-Higher-Education-Is/124292/

Now I understand that educational erosion makes a good almost alliteration (look at my blog title) however, they are not describing erosion.  They are describing weathering, and there is a fundamental difference.

Weathering can be broken up into two categories, chemical and physical. Physical is the easiest to understand, as it is simply mechanical processes which break apart the source rock. Examples include frost wedging, water running over rocks or rivers down cutting into the ground, wind sand blasting formations, or even animals walking over the same trail numerous times.

Chemical weathering is different.  This is when the minerals withing a source rock are changed into different minerals, which is often caused by water. Near Albuquerque are the three peaks, three inactive volcanoes which spewed basaltic lava thousands of years ago. On these volcanoes you can see the mechanical weathering from the water flowing down the slopes creating the classic V-shape indicative of mountain streams. However, the most interesting part is that where the black lava is along the stream, you can see how high the water gets when it does flow. As the once black rocks are turned white where they were submerged in the stream. This is due to chemical weathering, the Calcium Feldspars, indicative to basalts, are chemically weathered into calcite, a much softer mineral, which compromises the integrity of the formation.

Erosion, on the other hand, is all about transportation.  So while the forces of weathering and erosion may be the same, the processes are different. Weathering breaks down a mountain, while erosion spreads the pile of rubble far and wide, flattening out the landscape. Some of the mechanisms of erosion include landslides, turbidity flows, rivers, and wind.

So please remember, I'm on an educational journey and my education is not being torn down. Thank you

A Vestige of a Beginning

So it has been a week into my sixth semester of college and third as an official geology major and I am excited for the first time I have two junior level classes-Stratigraphy and Sedimentology as well as Structural Geology; this semester should be fun and interesting. After this week I feel pretty well acquainted with my classes, so I thought I might talk a bit about these classes and geosciences in general.

               

                I haven’t really had a chance to delve into my Structural Geology class, but my Strat/Sed class has been really interesting so far. Mostly we have discussed the foundation for this science; we stared with Steno and then going through the numerous missteps ending with Werner. What was really amazing to me was how these men, who did add quite a bit of knowledge to other geologic fields such as mineralogy, were so off the mark in how the layers of rocks were laid down.

               

                Werner in particular is a fascinating man.  His strong arm tactics probably held back geology for several decades, his students were completely indoctrinated into his field of geognosis which completely disregarded field observation and research, and his students were told that Werner knew everything there was to know and not to ask questions. This of course runs against the idea of an open dialogue which is necessary for science to flourish.

                To me what was truly amazing was learning about James Hutton and John Playfair; Hutton’s insistence on field research and use of the scientific method revolutionized the field. Hutton is one of those great historical characters who at first failed at everything he tried, but then ended up revolutionizing the world. Hutton bounced around from program to program in academia and eventually all over Europe. Hutton’s extensive education gave him the background to understand the processes at work, and his extensive travels allowed him to see numerous and varied landscapes which in turned allowed him to make connections between widely different lands and helped him understand that the Earth has been shaped by a myriad of processes.

                There is a cautionary tale to Hutton’s story, though.  Scientists have to be able to communicate their ideas; apparently of the numerous university courses Hutton took, English wasn’t one of them. This prevented his ideas from being communicated to the general public. Just listen to this piece on volcanoes and volcanic mountains: “a volcano should be considered as a spiracle to the subterranean furnace, in order to prevent the unnecessary elevation of land, and fatal effects of earthquakes; and we may rest assured that they, in general, wisely answer the end of their intention, without being in themselves an end, for which nature has exerted such amazing power and excellent contrivance.” The man liked to ramble and was not an enjoyable read; luckily for us and for the field of geology, Hutton had a close friend and traveling companion in John Playfair. Playfair had taken an English class and could write, so he basically translated Hutton’s work into understandable English.

                My professor is a strong proponent of teaching the historical foundation of the geosciences (this is my third class with him and he has started off every semester teaching at least some history), and while most of my classmates seemed bored by these lessons, I am fascinated by them and think they provide valuable insight. The failings of Werner and his contemporaries demonstrate the importance of the scientific method. These men assumed their Earth to be as unchanging as it appeared to be; however, had they put their conclusions to the test they would have found it lacking in proof and hopefully would have revised them to be more in keeping with the evidence at hand. These historical lessons teach us not to assume and to stay observant and keep our minds open which is a very important lesson for students just beginning their scientific careers.

                So maybe starting off a geosciences blog with a history lesson isn’t the brightest idea ever, but I really wanted to talk about this subject, and my friends and family just look at me like I’m crazy. My next post will be about some geologic feature in Southeastern New Mexico which I should have it up in a week and a half or so.