In geology, is there any current method to quantify tectonic movement for a given area and make comparisons between these areas?
Will the method act like these: for a given period of time, how many mountain ranges had formed? Or, how high had the mountain/mountains uplifted?
Hello!
This is an interesting question. I have heard a bit or two about this topic.
I will suggest reading the Encyclopedia of Geomorphology (Edited by A.S. Goudie, 2004), vol. 2, p. 1036 - "Tectonic Activity Indices". The following indices are described:
These methods are morphometric (based on measurements of landforms and their elements) and are designed to identify areas with tectonic movement.
Another useful book is Tectonic Geomorphology by Douglas W. Burbank and Robert S. Anderson (2001).
You can also search for geological and geomorphological papers about the area of interest. Case studies are usually the best starting point because they provide information about given areas for a given interval of time.
The most direct methods would be thermochronometry (also known as thermochronology). This uses dating of temperature-sensitive minerals in rocks to reveal when they were at various depths in the Earth, which when applied creatively can give uplift histories. This can be particularly effective if there's still a lot of surface relief in a region (i.e., there are still mountains there). Googling thermochronometry will probably get you in to this literature. There are some classic studies in the Alps that do this.
Things get harder for thermochronometry in deeper time, as the necessary dating methods go extinct or become less well constrained. In these earlier times, you will end up falling back on traditional geological tools: basin analysis, sediment provenance, metamorphic petrology, structural geology. These can be less precise, but will probably give you a decent sense of how many mountain building episodes a region has undergone.
Getting a sense of absolute elevation is hard. People have been trying to do this for the paleo-Himalayas for years, and last time I dipped into this literature, the various different methods were still all giving conflicting answers. I wouldn't trust anyone who claims to be able to do this to better than +/- 2 km for a mountain range that no longer exists.
Petko, above, is right that those methods will work pretty well for a mountain range that still exists and for which you want to understand tectonics over, say, the last million years. They won't work on timescales longer than about a million years into the past though.
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