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How clay is created in nature

Earlier today, I was thinking about clay…how it is strengthened when molecules overlap. This lead to pondering the organic material itself. I’ve always been curious about how things work and this tendency led to an interest in scientific processes. So, after looking at a few sites, I came across a description about the formation of clay in entry on the Absolute Astronomy site. It included everything I needed to know. Basically, clay is created when rocks weather over long periods of time, which makes chemical changes happen. According to the entry, rocks with silica eventually create “low concentrations of carbonic acid and other diluted solvents. These solvents, usually acidic, migrate through the weathering rock after leaching through upper weathered layers.” It said that slowly forming clays present in two ways, either as a “residual deposit” or, if we’re talking about thick clay formations, then by the sedimentary process after erosion and movement shifts it from its “original location of formation.” Clays are also found in marine environments, near big lakes or by “marine deposits.”  This would explain why there is so much naturally occurring clay in my area, at the end of the Burrard Inlet in Metro Vancouver. Many creeks feed into the inlet. Just on my street, alone, five creeks intersect the four-block long lane, then head downhill to the ocean. There has been much ancient and modern-day mudslide activity here. It has left big boulders and large river-type stones above  and below ground here. Ocean water is four blocks away, at present, but I don’t know where the waterline was in ancient times. Back to clay, though. Evidently, kaolin is formed on the spot, but other clays have moved by way of water and erosion. A type of clay is determined by different ways of grouping and categorizing. This source says there are up to four main types:

  • Kaolinite
  • Montmorillonite-smectite
  • Illite
  • Chlorite (sometimes considered a phyllosilicate)

Apparently, these are further broken down into some 30 odd pure clays, but the entry says that natural clays are most often a combination. Further description states that varve is clay that shows “visible annual layers” formed as the result of seasonal changes and that it is commonly found in former glacial lakes, which it says have very little movement. As I read about clay on this site, I was particularly interested in a unique type of clay called quick clay, which is a “marine clay indigenous to the glaciated terrains of Norway, Canada, Northern Ireland and Sweden. It is a highly sensitive clay, prone to liquefaction, which has been involved in several deadly landslides.”

In any event, I answered my initial question…how is clay created in nature? I am satisfied with what I learned and if I want to investigate further, I have several avenues….

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