RSNI - Manually revised location

MANUAL Location - Area: Alpi Graie , magnitude (M_L): 0.4
2025-09-07 04:08:44 (UTC)

Regional Seismic Network of Northwestern Italy (Distav, University of Genoa)
Posted on: 2025-09-08 09:57:00

Earthquake info - Manual location

Event - ID :	250907040757
Magnitude (M_L) :	0.4 +/- 0.2
Origin Time :	2025-09-07 04:08:44.288 (UTC)
Location :	Latitude: 45.696 N, Longitude: 6.816 E
Area :	Alpi Graie
Depth (km) :	4.88
Distances (km) :	10.6 --- La Thuile 15.3 --- Pre -Saint-Didier 16.4 --- Courmayeur 18.5 --- Morgex 20.5 --- Valgrisenche 20.6 --- La Salle 25.3 --- Avise 26.7 --- Rhemes-Saint-Georges 27.3 --- Arvier 27.3 --- Rhemes-Notre-Dame 27.3 --- Saint-Nicolas 28.8 --- Introd 30.5 --- Villeneuve 31.5 --- Saint-Rhemy-En-Bosses 32.2 --- Saint-Pierre 32.7 --- Valsavarenche 33.3 --- Aymavilles 33.9 --- Saint-Oyen 34.4 --- Sarre 35.0 --- Etroubles

Quality location estimate: Erh: 0.9 km, Erz: 1.3 km, Nf: 24, Gap: 104 °, Rms: 0.15

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.
RSL	FR	2025-09-07 04:08:47.740	0.008	0	-0.01	1.66	2025-09-07 04:08:49.405	0.040	0	-0.60	0.10	15.6
COURM	FR	2025-09-07 04:08:48.533	0.020	0	-0.04	1.59	2025-09-07 04:08:51.738	0.040	0	0.36	0.53	19.1
MRGE	IV	2025-09-07 04:08:49.190	0.011	0	0.04	1.58	2025-09-07 04:08:52.160	0.057	1	-0.20	0.88	21.7
REMY	GU	2025-09-07 04:08:51.000	0.016	0	-0.03	1.59	2025-09-07 04:08:55.661	0.267	7	0.13	0.96	31.7
LSD	GU	2025-09-07 04:08:51.550	0.019	0	0.27	0.68	2025-09-07 04:08:55.940	0.106	3	0.04	1.30	36.8
OGMO	FR	2025-09-07 04:08:54.507	0.020	0	0.10	1.25	2025-09-07 04:09:01.071	0.040	0	-0.12	1.14	55.4
LATO	IV	2025-09-07 04:08:56.621	0.020	0	0.24	0.85	2025-09-07 04:09:04.204	0.040	0	-0.16	1.00	67.0
RSP	GU	2025-09-07 04:08:57.400	0.020	0	0.45	0.39	2025-09-07 04:09:05.242	0.040	0	-0.23	0.86	70.5
CANI	GU	2025-09-07 04:08:57.592	0.020	0	0.02	1.38	2025-09-07 04:09:06.170	0.040	0	-0.10	1.08	74.2
RRL	GU	2025-09-07 04:08:59.503	0.020	0	-0.21	0.90	2025-09-07 04:09:09.530	0.373	8	-0.72	0.29	86.4
BHB	GU	2025-09-07 04:09:02.470	0.052	2	0.41	0.52	2025-09-07 04:09:14.203	0.040	0	-0.01	0.98	102.0

Local magnitude (M_L) calculation results

Station	Net	Channels	Stat. Mag.	Wood-And. Ampl.	Dist. (km)	Azimuth
COURM	FR	HH	0.52	9.63e-2	19.1	39
MRGE	IV	HH	0.16	2.82e-2	21.7	66
REMY	GU	HH	0.09	1.38e-2	31.7	59
LSD	GU	HH	0.54	2.91e-2	36.8	137
RSP	GU	HH	0.45	6.71e-3	70.5	150
CANI	GU	HH	0.38	4.76e-3	74.2	113
RRL	GU	HH	0.45	2.70e-3	86.4	181
BHB	GU	HH	0.55	3.09e-3	102.0	160

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.
(°)

COURM

HHZ

1.7143e-5

2.0494e-6

7.1102e-7

1.6554e-7

7.8680e-8

2.5708e-5

3.6977e-6

1.4208e-7

4.2681e-8

19.1

COURM

HHN

1.3425e-5

1.5890e-6

9.6838e-7

3.4202e-7

1.2686e-7

2.8367e-5

4.8419e-6

1.9941e-7

3.5872e-8

19.1

COURM

HHE

1.1884e-5

1.5092e-6

9.4543e-7

3.7175e-7

1.3216e-7

2.1089e-5

5.3540e-6

1.9387e-7

3.7091e-8

19.1

MRGE

HHZ

9.4754e-6

8.2746e-7

1.6715e-7

5.5989e-8

2.4045e-8

4.3602e-6

7.0312e-7

4.9444e-8

1.4203e-8

21.7

MRGE

HHN

1.0789e-5

9.2262e-7

1.7143e-7

7.1769e-8

3.5942e-8

8.4144e-6

7.5811e-7

6.9964e-8

1.7121e-8

21.7

MRGE

HHE

9.1547e-6

1.0293e-6

1.8896e-7

6.5227e-8

3.4826e-8

8.8527e-6

9.3977e-7

7.2068e-8

1.6577e-8

21.7

REMY

HHZ

1.8783e-6

2.8624e-7

9.3425e-8

2.6715e-8

1.4219e-8

2.7068e-6

4.8214e-7

2.4202e-8

4.9788e-9

31.7

REMY

HHN

1.4261e-6

1.8746e-7

1.2032e-7

5.8299e-8

3.3120e-8

2.7815e-6

5.9359e-7

4.8020e-8

5.1360e-9

31.7

REMY

HHE

1.8183e-6

2.7257e-7

1.3384e-7

4.4152e-8

1.7833e-8

4.3443e-6

4.5756e-7

3.0461e-8

6.2141e-9

31.7

LSD

HHZ

3.6278e-6

3.6809e-7

1.3464e-7

4.9240e-8

2.1367e-8

6.0264e-6

6.7505e-7

3.5704e-8

8.0730e-9

36.8

137

LSD

HHN

5.6134e-6

6.3018e-7

2.4535e-7

6.9392e-8

3.7625e-8

1.0160e-5

1.1861e-6

6.8165e-8

1.2501e-8

36.8

137

LSD

HHE

4.5523e-6

5.7514e-7

2.4702e-7

5.7764e-8

2.9368e-8

8.5757e-6

1.0121e-6

5.1936e-8

1.0730e-8

36.8

137

RSP

HHZ

5.0727e-7

6.4578e-8

4.0421e-8

1.6588e-8

8.9972e-9

1.0401e-6

1.5869e-7

1.3819e-8

1.8600e-9

70.5

150

RSP

HHN

7.3302e-7

1.2266e-7

6.4307e-8

1.8385e-8

9.4443e-9

1.8278e-6

3.9118e-7

1.4883e-8

2.8550e-9

70.5

150

RSP

HHE

5.9556e-7

1.0180e-7

6.3081e-8

1.9403e-8

8.9509e-9

1.3296e-6

3.3459e-7

1.3844e-8

2.4923e-9

70.5

150

CANI

HHZ

6.6775e-7

9.4144e-8

4.5854e-8

1.4806e-8

7.2445e-9

1.9380e-6

1.7683e-7

1.0956e-8

2.0815e-9

74.2

113

CANI

HHN

6.4933e-7

8.0907e-8

3.9700e-8

1.1289e-8

5.4811e-9

1.9168e-6

1.9429e-7

1.0739e-8

1.7592e-9

74.2

113

CANI

HHE

7.2213e-7

8.9984e-8

5.0421e-8

2.2247e-8

1.2327e-8

2.2422e-6

2.4017e-7

1.7069e-8

2.1256e-9

74.2

113

RRL

HHZ

1.0955e-7

1.5153e-8

1.0502e-8

8.3998e-9

5.8485e-9

2.6067e-7

4.6475e-8

9.3134e-9

5.9277e-10

86.4

181

RRL

HHN

1.2446e-7

2.9676e-8

2.3099e-8

1.0960e-8

6.3523e-9

4.1055e-7

1.2512e-7

8.8362e-9

1.1421e-9

86.4

181

RRL

HHE

1.0391e-7

2.3232e-8

1.8951e-8

1.1617e-8

6.4916e-9

2.6442e-7

1.2202e-7

7.6848e-9

7.3165e-10

86.4

181

BHB

HHZ

3.2490e-7

6.3820e-8

2.8372e-8

2.5379e-8

6.8005e-8

1.2647e-6

1.0850e-7

1.4927e-7

6.2783e-9

102.0

160

BHB

HHN

2.1127e-7

4.3398e-8

3.1989e-8

1.2211e-8

8.9414e-9

7.2532e-7

1.2055e-7

1.7772e-8

1.0267e-9

102.0

160

BHB

HHE

2.2206e-7

2.9533e-8

2.2545e-8

1.0405e-8

7.8794e-9

5.0360e-7

7.9983e-8

1.4278e-8

9.7107e-10

102.0

160

*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: Alpi Graie , magnitude (ML): 0.4 2025-09-07 04:08:44 (UTC)

MANUAL Location - Area: Alpi Graie , magnitude (M_L): 0.4
2025-09-07 04:08:44 (UTC)