RSNI - Manually revised location

MANUAL Location - Area: Lunigiana , magnitude (M_L): 1.0
2025-08-09 06:44:34 (UTC)

Regional Seismic Network of Northwestern Italy (Distav, University of Genoa)
Posted on: 2025-08-09 15:29:30

Earthquake info - Manual location

Event - ID :	250809064157
Magnitude (M_L) :	1.0 +/- 0.2
Origin Time :	2025-08-09 06:44:34.705 (UTC)
Location :	Latitude: 44.184 N, Longitude: 9.916 E
Area :	Lunigiana
Depth (km) :	6.24
Distances (km) :	1.8 --- Bolano 2.5 --- Santo Stefano di Magra 3.5 --- Podenzana 4.9 --- Follo 5.3 --- Vezzano Ligure 5.4 --- Aulla 7.0 --- Tresana 7.4 --- Arcola 8.7 --- Sarzana 9.2 --- Calice al Cornoviglio 9.7 --- Fosdinovo 11.6 --- La Spezia 11.9 --- Beverino 11.9 --- Lerici 12.3 --- Castelnuovo Magra 12.5 --- Villafranca in Lunigiana 12.6 --- Ricco del Golfo di Spezia 13.4 --- Ameglia 13.4 --- Licciana Nardi 14.6 --- Ortonovo

Quality location estimate: Erh: 0.6 km, Erz: 0.8 km, Nf: 35, Gap: 88 °, Rms: 0.20

Manual location results

Station	Net	P arrival time	P pick err	P pick weight	P res	Nll weight	S arrival time	S pick err	S pick weight	S res	Nll weight	Dist.
AUL	IT	2025-08-09 06:44:36.979	0.020	0	0.46	0.19	2025-08-09 06:44:37.790	0.040	0	-0.01	2.01	8.2
PLMA	IV	2025-08-09 06:44:38.150	0.010	0	-0.03	2.03	2025-08-09 06:44:40.150	0.064	1	-0.58	0.53	16.9
FIVI	GU	2025-08-09 06:44:38.447	0.020	0	-0.14	1.32	2025-08-09 06:44:41.317	0.040	0	0.00	1.92	19.0
EQUI	GU	2025-08-09 06:44:38.910	0.013	0	0.02	1.99	2025-08-09 06:44:41.290	0.057	1	-0.63	0.50	20.1
CAR	IT	2025-08-09 06:44:39.587	0.020	0	0.05	1.75	2025-08-09 06:44:42.681	0.040	0	-0.39	0.53	25.4
VRL	IT	2025-08-09 06:44:40.990	0.020	0	-0.07	1.84	2025-08-09 06:44:45.322	0.040	0	-0.44	0.57	32.9
MSSA	IV	2025-08-09 06:44:41.450	0.019	0	0.05	1.74	2025-08-09 06:44:45.671	0.173	5	-0.82	0.32	35.6
GRAM	GU	2025-08-09 06:44:42.060	0.021	1	0.60	0.16	2025-08-09 06:44:47.104	0.040	0	1.01	0.02	36.7
VLC	MN	2025-08-09 06:44:41.870	0.021	1	0.29	0.39	2025-08-09 06:44:46.500	0.110	3	-0.19	1.20	38.1
SARM	GU	2025-08-09 06:44:42.130	0.022	1	0.02	1.88	2025-08-09 06:44:46.900	0.114	3	-0.72	0.40	39.1
CME	IT	2025-08-09 06:44:42.050	0.020	0	-0.21	0.97	2025-08-09 06:44:46.527	0.040	0	-1.35	0.08	40.4
BVT	IT	2025-08-09 06:44:42.540	0.020	0	-0.09	1.68	2025-08-09 06:44:48.292	0.040	0	-0.11	1.45	41.4
ERBM	IV	2025-08-09 06:44:44.210	0.027	1	0.26	0.54	2025-08-09 06:44:50.377	0.514	9	-0.46	0.69	47.8
CARD	GU	2025-08-09 06:44:43.500	0.060	2	0.18	0.90	2025-08-09 06:44:49.169	0.141	4	-0.57	0.56	48.8
MAIM	GU	2025-08-09 06:44:44.630	0.029	1	0.05	1.65	2025-08-09 06:44:50.550	0.159	4	-1.43	0.08	55.2
GSCL	GU	2025-08-09 06:44:45.590	0.065	3	-0.07	1.61	2025-08-09 06:44:53.215	0.209	6	-0.62	0.55	56.9
POPM	GU	2025-08-09 06:44:46.830	0.036	1	0.06	1.50	--:--	-.---	-	-.--	-.--	69.1
PII	IV	2025-08-09 06:44:47.070	0.041	2	-0.17	1.28	--:--	-.---	-	-.--	-.--	71.0
RNCA	GU	2025-08-09 06:44:49.700	0.042	2	0.65	0.19	--:--	-.---	-	-.--	-.--	83.4

Local magnitude (M_L) calculation results

Station	Net	Channels	Stat. Mag.	Wood-And. Ampl.	Dist. (km)	Azimuth
PLMA	IV	HH	1.28	6.69e-1	16.9	199
FIVI	GU	HN	1.26	5.22e-1	19.0	70
EQUI	GU	HH	0.85	1.88e-1	20.1	96
CAR	IT	HN	1.09	2.08e-1	25.4	287
MSSA	IV	HH	0.70	4.42e-2	35.6	295
GRAM	GU	HH	0.87	1.14e-1	36.7	19
VLC	MN	HH	1.16	8.07e-2	38.1	94
SARM	GU	EH	1.02	9.40e-2	39.1	90
BVT	IT	HN	1.32	1.40e-1	41.4	340
ERBM	IV	EH	0.84	3.42e-2	47.8	56
MAIM	GU	HH	0.99	3.26e-2	55.2	123
GSCL	GU	HH	0.91	2.82e-2	56.9	71

Results of PGA, PGV, IH, spectral amplitudes (SA) values calculation

Station

Net

Channel

PGA
(g)

PGV
(m/s)

IH 0*
(m)

IH 1*
(m)

IH 2*
(m)

Sa(T=0.10)
(g)

Sa(T=0.30)
(g)

Sa(T=1.00)
(g)

Sa(T=3.00)
(g)

Dist.
(km)

Azim.
(°)

*IH (Housner Intensity) calculated on the velocity spectrum (SV) between 0.1 and 0.5 s (IH0), 0.1 and 1.0 s (IH1), 0.1 and 1.5 s (IH2)

MANUAL Location - Area: Lunigiana , magnitude (ML): 1.0 2025-08-09 06:44:34 (UTC)

MANUAL Location - Area: Lunigiana , magnitude (M_L): 1.0
2025-08-09 06:44:34 (UTC)