Significant Events – April 30, 2016

Strong aftershocks continue to rattle Vanuatu

Latest Events [USGS/EHP]

• M5.1 (16.262°S, 167.205°E) 27km SW of Lakatoro, Vanuatu 2016-04-30 09:26:30 UTC; depth=12.1km
• M4.7 28km SW of Lakatoro, Vanuatu 2016-04-30 08:45:57 UTC 7.3 km
• M6.0 (16.306°S, 167.188°E) 32km SW of Lakatoro, Vanuatu 2016-04-30 08:35:42 UTC; depth=4.8km
• M5.0 31km SW of Norsup, Vanuatu 2016-04-30 04:38:28 UTC; depth=10.0km
• M4.8 48km W of Norsup, Vanuatu 2016-04-29 22:50:14 UTC;depth=19.3km

Philippines: Drought and dry spells [OCHA]

Some 42 per cent of the Philippines is currently experiencing drought or dry spells brought on by El Niño effect. As of 15 April, 39 provinces, cities, municipalities and villages have declared a state of calamity. The worst affected areas are Mindanao and the Visayas regions. According to UN OCHA, around 181,687 farmers and 224,834 hectares of agricultural land have been affected since January 2016. Already, an estimated CHF 81 million in agricultural production has been lost. Rainfall for March was again well below normal.

Most of the affected areas are in Mindanao. According to the Department of Social Welfare and Development (DSWD), as of April 16, a total of 457,497 families or 2,124,790 persons from Regions NCR, I, II, III, IV-A, IV-B, VI, VII, X, XI, XII, and ARMM have been affected by El Nino.

Significant Quakes Strike Both Sides of Pacific; NZ Volcanoes Awaken

DET

M7.0 earthquake strikes Vanuatu followed by M6.6 at Northern East Pacific Rise

M7.0 earthquake occurred beneath the island of Melampa in the Vanuatu island chain of the southwest Pacific Ocean as a result of thrust faulting on or near the boundary between the Australia and Pacific plates, USGS/EHP reported.

EQ Details

Magnitude: 7.0Mw [1km SE of Norsup, Vanuatu]
Location: 16.074°S, 167.393°E; depth=27.2 km (16.9 mi)
Time: 2016-04-28 19:33:24 (UTC)
Distances:

1.0km (0.6 mi) SE of Norsup, Vanuatu
64.0km (39.8 mi) SSE of Luganville, Vanuatu
208.0km (129.2 mi) NNW of Port-Vila, Vanuatu
536.0km (333.1 mi) N of We, New Caledonia

Magnitude: 6.6Mw [Northern East Pacific Rise]
Location: 10.271°N, 103.715°W; depth=10.0 km (6.2 mi)
Time: 2016-04-29 01:33:38 (UTC)
Distances:

• 602.0 km (374.1 mi) E of Clipperton Island, France
• 838.0 km (520.7 mi) SSW of Acapulco de Juarez, Mexico
• 838.0 km (520.7 mi) SSW of Tecpan de Galeana, Mexico
• 844.0 km (524.4 mi) SSW of Petatlan, Mexico
• 1,126.0 km (699.7 mi) SSW of Mexico City, Mexico

NO major tsunami threats generated by the two quakes.

Two NZ Volcanoes Show Signs of Unrest

Mt Ruapehu

A volcanic earthquake swarm has been reported at Mt Ruapehu. The seismicity began on April 26. The Crater Lake temperature, which has been rising since October 2015,  has now reached 40°C (from 25°C in mid-April). Mt Ruapehu remains at Volcanic Alert Level 1 (Minor volcanic unrest), Geonet reported.

White Island

A minor eruption occurred at White Island (Whaakari) at about 11:00 pm on Wednesday, 27 April 2016. Moderately elevated seismic activity is occurring, said Geonet. Additionally:

• Water level in the Crater Lake has fallen by 2m in the last 2 weeks.
• Lake temperature has increased by 2°C, to 58°C, since February.
• SO2 output ranging from 90 to 480 tons per day reported over the last 5 weeks, but said to be typical values for White Island.

“A dark-green ash deposit from the eruption covers at least 80% of the floor of Main Crater, and up the sides of the crater wall on both the north and south sides. At a distance of 500 m from the eruption site the ash deposit is about 5 mm thick. The green colour is due to minerals on the ash.”

Alert Level was initially raised to Level 3 (Minor Volcanic Eruption) and the Aviation Color Code to Orange. The Alert Level was lowered to 2 from 3 on Thursday.