The phrase "Orthotectonic Caledonides of Scotland" sent me to my
"Glossary of Geology" to see what orthotectonics meant. The
definition given was "alpinotype tectonics", which was separately
defined as "The tectonics of alpine mountain belts, regardless of
their age, which are produced from orthogeosynclines. They are
characterized in their internal parts by deep seated plastic folding
and plutonism, and in their external parts by lateral thrusting,
which has produced nappes, thrust sheets, and closely crowded folds."
I then looked up "Orthogeosyncline" and found it to be "A geosyncline
between volcanic and continental cratons, containing both volcanic
(eugeosynclinal) and non volcanic (miogeosynclinal) belts (Stille,
1935, pp. 77-97). I feel uneasy about use of the prefix "ortho" in
the orthotectonics if it is meant to refer to the concept of
orthogeosyncline" which has disappeared from the modern literature.
Can anyone enlighten me with a more up to date definition of
"orthotectonics"?
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