tphase vine de la Tertiary Phase. Tertiary Phase sunt al 3-lea val de unde care se propaga in urma unui cutremur subacvatic.
Prescurtarea tehnica de la Tertiary Phase este chiar asa: tphase

What is a T-phase?

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What is a T-phase?

A "T-phase" or "T-wave" is an acoustic phase from an earthquake that travels through the ocean. The "T" stands for "tertiary", as in: P-waves are "primary", S-waves are "secondary", and T-waves are "tertiary", because they travel the slowest and so arrive 3rd. Basically, when an earthquake occurs in the earth's crust under the ocean, the usual crustal phases are generated (P and S waves), but in addition part of the energy goes into the ocean as acoustic energy, and that is the T-wave. It's basically the seafloor rumbling. Not all earthquakes generate T-waves (since they need to be near water). T-waves are typically recorded by hydrophones, but on some islands seismometers sometimes record T-wave signals that have been converted to crustal phases when they hit the island. Similarly, we sometimes "hear" big earthquakes located in Hawaii, because enough of the earthquake energy gets converted into T-waves on the island flanks.

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