I grandi terremoti possono essere preceduti da un'accelerazione dello scivolamento della faglia rilevabile fino a 2 ore prima del sisma. Ad attestarlo sono le misurazioni Gps concernenti più di 90 scosse, con magnitudo pari o superiore a 7, avvenute in varie parti del mondo.
Lo studio, pubblicato sulla rivista scientifica Science da due specialisti del Centro nazionale di ricerca scientifica francese (Cnrs), segna un ulteriore passo verso una possibile individuazione di segnali precursori dei sismi, che possano portare ad un sistema di allerta precoce.
"Questo studio dimostra come la Terra ci mandi continuamente segnali che ancora non misuriamo adeguatamente, ma che possono in realtà darci informazioni fondamentali sui meccanismi della dinamica della crosta terrestre", ha commentato il geologo Carlo Doglioni, che in Italia presiede l'Istituto nazionale di geofisica e vulcanologia (INGV).
Gli esiti aprono prospettive promettenti per la previsione dei grandi terremoti e "confermano che anche la rete Gps può fornire informazioni preziose da monitorare in tempo reale". I dati, precisa tuttavia l'esperto, non sono però ancora abbastanza solidi "per affermare con certezza che lo scivolamento della faglia possa essere considerato un segnale premonitore affidabile", dato che l'analisi è risultata coerente per 58 scosse su 90".
Notiziario 23:00 del 20.07.2023
RSI New Articles 20.07.2023, 23:10
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