Following an article published in the Corriere del Mezzogiorno on 20 April 2018, "Boschi: epicenter known immediately. Ischia earthquake, it is yellow on the error" signed by Roberto Russo, the request for correction is reported in its entirety
In relation to the article in question, what is reported in relation to the reconstruction of the timing of the correct assessment of the magnitude and location of the event of August 21, 2017 in Ischia is categorically denied.
It is not true that the estimate of the magnitude of the earthquake was incorrect or modified: the first evaluation made by the seismic rooms of Rome and Naples (local magnitude 3.6 and duration magnitude 4.0, which are different techniques and numbers) was also confirmed in the days and months following the earthquake when INGV started all possible processing to obtain the most reliable value (M moment 3.9). Therefore, there was no change, let alone an error, in the calculation of the magnitude issued on the evening of 21 August.
It is false that the best localization of the event in question was already obtained on August 21st. This thesis, in addition to being clearly illogical, is totally unfounded as evidenced by all the official documents that INGV has shared with the competent institutions, and also by making them available on its website http://cnt.rm.ingv.it/event/16796811 The location provided on the evening of August 21st was, as always happens, the best with the data available at that time. What was achieved in the days following the earthquake led to a more reliable location of the event, placing it at a depth of 1.7 km under Casamicciola. This conclusion was reached on 24 August and promptly communicated to the competent bodies.
Roberto Russo's article states that the Institute communicated the location 10 km from the real epicenter while this data is clearly incorrect: the refinement of the location was about 5 km for the horizontal and 3.3 km for the vertical and it happened without any solicitation from the Civil Protection. The relocation was below the uncertainty of about 10 km in the positioning of the epicenter, a value due to the number of stations and their position with respect to the epicenter (called azimuthal gap, or angle in which there are stations, which in this case was 176°!). In this regard, see the report made public by INGV with all the relative data: https://ingvterremoti.files.wordpress.com/2017/09/rapporto-di-sintesi-sul-terremoto-6-settembre-2017_l.pdf For seismic events in similar coastal locations, ie without stations at sea, the uncertainty remains on these values and re-locations with changes comparable to that of the August 21 event are the routine.
There is talk of events never clarified in the Monitoring Rooms of the Vesuvius Observatory and the National Earthquake Centre, CNT. The surveillance protocols, set out in the Convention between the Civil Protection Department (DPC) and INGV, by their intrinsic nature, being codified, cannot give rise to ambiguous situations.
INGV has communicated the data and the elaborations that have been gradually realized in the most total transparency and speed, including also the fundamental ones of the effect of the site detected and of the damage.
Subsequent research has made it possible to carry out an important research published in a prestigious journal with colleagues from the IREA - CNR Institute for Electromagnetic Sensing of the Environment and the DPC, which explains the main causes of the earthquake (see http://comunicazione.ingv.it/index.php/comunicati-e-note-stampa-2/1728-la-subsidenza-del-monte-epomeo-possibile-origine-per-i-maggiori-terremoti-di-ischia).
The interview with the undersigned on 22 August is repeatedly and artfully cited: in the passage to the news, for dissemination purposes and without any geographical coordinates, a reflection seismic section acquired west of Ischia was shown, in which the faults that from island project towards the Tyrrhenian Sea; such active structures exist and are documented in the southern part of the TIR10-13 section published in a recent article (https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016TC004198).
INGV is the most important geophysical institution in Europe and is a national heritage with highly professional personnel, recognized internationally and with a series of observational networks of inestimable value for the scientific community and above all for citizens. Questioning its competence, impartiality and efficiency means not knowing how the body works and seriously damaging the image of a public institution whose staff works 24/7 to ensure public safety".
INGV President
Carlo Doglioni