Her theme is favorite Geology words
I have a lot of favorite geologic words and its hard to choose just one but today I'm going to go with one that I had trouble remembering and saying. I had fun coming up with a way to remember it. Sometimes this word takes a few tries for me to spill it out. Because it took more than one try to get it right it helped me with its meaning.
Bi
Buy fur
Buy fur cake
Bifurcate
That's it Bifurcating streams.
BIFURCATING STREAMS
I learned that terminology to describe streams. Bifurcate means: to be forked or split or be Y-shaped. I had a hard time remembering that when describing dendritic drainage patterns (another favorite geologic phrase I memorized). Dendritic drainage occurs when the underlying rock is uniform in resistance and the tributaries flow down to a main stream, like a tree with its branches and trunk (Principles of Geology 3rd ed. by Gilluly, Waters & Woodford 1968 pgs 239-40). You get bifurcation when you go both up stream and down stream when the water empties into a lake or ocean.
And while I'm at it since I'm talking about favorite words associated with streams and rivers I have to add Alluvial fans (pg 236-7) and Thalweg (pg 231). I just love the sounds of those words as I say them.
Alluvial fans form when the sediments are deposited from a stream that comes from steeper slopes onto a more gentle sloped area. The water splits (bifurcates) as it spreads out over a wider area. (Evelyn already has used Alluvial so I don't feel right using it again). I did get a couple of good picture of bifurcation when I went hot air ballooning in Arizona.
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| Deadman wash, Biscuit Flat, near Carefree hwy Arizona, showing bifurcation |
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| New River, Biscuit flat near Carefree Hwy, Arizona |
And I liked this one because you can see where the water would flow to the top of the photo and the two branches come together forming the Y-shape.
Thalweg is the line following in the deepest part of a river channel. Sorry no pictures here.
So I guess my favorite geologic word is BIFURCATE.
