Questions tagged [tectonics]

Tectonics is the application of field geology, petrology, geochemistry, geochronology, geophysics, remote-sensing, modeling and multidisciplinary studies to explains the evolution, structure, and deformation of Earths lithosphere.

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Given the movement of the tectonic plates in the past 5,000 years, how can the alignments of megaliths around the planet still be accurate?

Many of the worlds oldest megaliths are aligned with the cardinal points like the Great Pyramid which is said to be within an accuracy of better than four minutes of arc, or one-fifteenth of one ...
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What happens to the earth after volcanism/tectonics slows?

If we move far enough into the future that the core begins to solidify to the point that volcanism and tectonics are non-existent, what does the surface of the planet begin to look like? Does the ...
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For slab rollback, what allows the subducting plate to begin descending at a steeper incline?

I recently learned about slab rollback, specifically of the Juan de Fuca plate subducting underneath the North American plate. From what I understand, the subducting plate over time begins descending ...
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Is the Ethiopian Plateau uplift still ongoing?

The rift zones around the Ethiopian Plateau, Mid Ethiopian Rift, are stil tectonically active since Somalia is separating from Nubia at a rate of 6–7 mm annually[1], and Arabia is rotating counter-...
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Determining rotation of a bending detachment fault system

I would like to obtain the angle of rotation (𝛿θ) of a detachment fault (or oceanic core complex) after X meters of rock displaced during spreading at a mid-ocean ridge. I have a differential ...
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Coloring maps by feature orientation

I live in the SF Bay Area where many, but not all, geological features are oriented parallel to the San Andreas Fault. I was wondering if there’s a type of map where ridges are colored by compass ...
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75 views

Where and how big was Sicily between 5 and 1 Ma ago?

Sicily is a geologically complex island which seems to have been extensively studied geologically and from a tectonically point of view. There are an overwhelming number of papers dealing with the ...
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Does fold tightness correlate to deformation intensity?

I'm studying a migmatite with two overprinting fold structures. The first (Dn+1) is tight and the second (Dn+2) is gentle. Would it be fair to assume that, since Dn+1's tightness is, well, tighter, ...
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Learn geological properties of the horizon through density of the rocks

It is possible to evaluate the geological structure of a basin based on gravimetric data. But if one doesn't have gravimetric data, how can one learn the geological structure and properties of a ...
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Understanding certain phrases in the article “Footwall topographic development during continental extension”

I am currently attempting to read the article "Footwall topographic development during continental extension". The article and its abstract can be found here. When reading the abstract, I ...
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Determining the spatial orientation of a fault given ground acceleration magnitude in different directions

Accelerographs measure ground acceleration in three different components of motion: east-west, north-south, and vertically (up-down). I know that fault orientation is important here, so let's say we ...
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How to calculate mountain front sinuosity index using DEM?

In tectonic geomorphology the Mountain front sinuosity index is one of the morphometric indexes. Smf = Lmf/Ls I have a DEM, so how do I use it to find the value? According to this diagram do I have ...