Geology glossary

Updated: Jun 8, 2023 02:48 GMT - refresh

tectonic: Earthquakes

The adjective "tectonic" refers to processes, properties, or resulting features related to the deformation (breaking and slow, plastic deformation) of rocks over large sections of the upper mantle and crust (lithosphere).
It is usually applied to large-scale features and processes, in the km scale and app. Smaller miniature tectonic processes are sometimes called micro-tectonic.

Related keywords (1):
intraplate
tectonic faultSynonym of: fault: Earthquakes

Illustration of the main types of tectonic faults (source: USGS)

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tephrite: Volcanology

Tephrite is an type of volcanic (extrusive) rock with low silica content, similar to basalt, but containing foid minerals (e.g. nephelinite, leucite) along with plagioclase.
The composition of tephrite is called tephritic.
tephritic: Volcanology

Tephritic refers to the mineral composition of tephrite, an type of volcanic (extrusive) rock with low silica content, similar to basalt, but containing foid minerals (e.g. nephelinite, leucite) along with plagioclase.
tremorSynonym of: volcanic tremor: Volcanology

Seismogram signal examples from volcanic earthquakes: Volcano Tectonic (VT) Low Frequency (LF), hybrid (mix of VT and LF), Very Low Frequency (VLF), and Tremor. Volcano name/date in lower left. (image: USGS)

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tumulus: Volcanology

Tumulus with strange shapes, on the lava flow field of the 1614-24 eruption of Mt. Etna, Italy.

From Latin "tumulus" = "little hill", tumuli (pl.) are uplifted sections of pahoehoe lava crust caused by pressure from still fluid lava accumulating beneath the hardened crust.

Tumuli are a characteristic feature of all pahoehoe lava flow fields, such as prominent on Kilauea volcano, Hawaii, but also many other basaltic volcanoes including Etna. Read all

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