July 31 , 2016. EN. Tatara-San Pedro , Nishinoshima , Turrialba , Kilauea .

Home / blog georges Vitton / July 31 , 2016. EN. Tatara-San Pedro , Nishinoshima , Turrialba , Kilauea .

July 31 , 2016. EN. Tatara-San Pedro , Nishinoshima , Turrialba , Kilauea .

July 31 , 2016.

 

Tatara-San Pedro , Chile :

 

Special report of Volcanic Activity (REAV)
Maule Region.
27th July 2016.
PM 6:40 p.m. (local).

The National Geology and Mining Service (SERNAGEOMIN) describes the following information obtained by monitoring equipment processed and analyzed by the Volcanological Observatory of Southern Andes, about the central data interpretation of the Tatara -San Pedro volcano monitoring  :
Wednesday, July 27, 2016 at 18h 15 local time (22: 15GMT), the monitoring stations near the Tatara-San Pedro volcano, recorded one (1) earthquake associated with rock fracturing (Volcano-Tectonic) , located 10.7 km south-southwest (SSO) of the main crater.

Afficher l'image d'origine


The location obtained was as follows:
TIME OF ORIGIN: hl 6:15 p.m. (GMT -4)
LATITUDE: 36 ° 05’00 « South, LONGITUD: 70 ° 54’32«  West
Depth: 7.39 km
LOCAL MAGNITUDE : 3.0 (ML)
OBSERVATIONS:
Before this event VT another similar event was recorded but of lesser magnitude (M 2.9).
The level of technical volcanic alert remains green.
SERNAGEOMIN continuous online monitoring and report timely to the changes in volcanic activity in the region.

tatara san pedro

The San Pedro-Pellado volcanic complex (also known as San Pedro-Tatara) has been active from the Pliocene to the Holocene. The Tatara-San Pedro edifice overlies the deeply eroded Pellado stratovolcano; both were constructed within the 6 x 12 km Río Colorado caldera, which formed during an eruption about 0.5 million years ago. The Tatara basaltic-andesite shield volcano at the western end of the complex contains stacked sequences of up to 100 or more lava flows forming up to 1500 m of relief. The glacier-filled summit crater of the 3621-m-high dominantly andesitic San Pedro stratovolcano, which overlies the Tatara edifice, contains a young scoria cone that was the site of the most recent eruptions. A major Holocene E-flank debris avalanche filled the Río de la Puente valley to the south and was followed by eruptions originating within the avalanche scarp low on the east flank that produced lava flows down the Estero Pellado drainage. No historical eruptions have been recorded, but fumaroles are found SE of Pellado.

Source : Sernageomin , GVP.

Photo : Jorge Romero , Michael Dungan.

 

Nishinoshima , Japan :

Ban on access to the island Nishinoshima?

30 July 2016. The Environment Ministry is considering banning people from Nishinoshima island, which is part of the Ogasawara Islands, a remote part of Tokyo. According to the ministry, Nishinoshima is the world’s sole “natural experimental site,” and its local ecological system is expected to grow from scratch having almost been destroyed by volcanic eruptions starting in 2013.

The ban is being considered in order to prevent people who visit the island from taking non-native flora and fauna with them. The Japan Meteorological Agency will shortly reduce the areas on the island that are on alert for eruptions.

The Environment Ministry plans to dispatch a research team there as early as October as a step toward discussing protective measures.

Nishinoshima is a state-owned uninhabited island where grasses and low trees used to grow, and it was a breeding site by seabirds such as the booby. However, the island’s plants were almost lost due to lava discharged in a volcanic eruption. Since then, the total land area has grown to 268 hectares — 12 times its original size of 22 hectares.

nishinoshima

No further eruptions have been confirmed since November last year. The JMA has decided it will soon reduce the area on alert for eruptions — currently the entire island — to a 500-meter radius around the crater having determined that volcanic activity has decreased. The move will open up part of the land area and could encourage researchers to visit the island.

The Ogasawara Islands, known as the Galapagos of the East, were registered as a natural World Heritage site in 2011. Researchers say its ecological system started with seeds that were carried by birds flying over the islands, or nuts that drifted ashore. Nishinoshima’s new ecological system is expected to keep growing. This could provide clues about how the ecology of the Ogasawaras developed.

 

nishinoshima

With this in mind, the ministry started considering protective measures, including legally registering the island as a wilderness area. However, an island needs to be least 300 hectares to be designated as a wilderness area. Because Nishinoshima island does not fulfill this criteria, a review on the rule will also be considered.
The ministry aims to buy time by implementing restrictions such as reducing the number of people who can visit the island; ensuring visitors wear brand-new clothing, shoes and bags; and ensuring visitors and their baggage are soaked in sea water to wash away any plant seeds or other flora and fauna. “We will restrict landings as much as possible. Regarding researchers who wish to visit the island, we will demand they thoroughly comply with the rules,” a ministry official said.

Source :   JAPAN TIMES.

Photos : Japan Coast Guard

 

Turrialba , Costa-Rica :

After the eruptions recorded earlier in the day of yesterday on the Turrialba volcano, it was noted sustained episodes of tremors from 8h00 am until  9h 30 and 2:19 p.m. until time of issuance of this report accompanied by passive sporadic emissions of ash.

Currently, a plume of gas and water vapor is observed by RSN surveillance cameras at the top of the volcano. The winds have maintained to the Southwest a predominant direction according to IMN weather station. The RSN keeps track of the evolution of the activity.

Source : Ovsicori

 

Kilauea , Hawai :

19°25’16 » N 155°17’13 » W,
Summit Elevation 4091 ft (1247 m)
Current Volcano Alert Level: WATCH
Current Aviation Color Code: ORANGE

kilauea

Activity Summary:
Eruptive activity continues at Kilauea Volcano’s summit and East Rift Zone. The 61G lava flow extending southeast of Pu’u ‘O’o continues its Kamokuna Ocean entry and poses no threat to nearby communities. The lava lake at Halema’uma’u Crater continues to circulate and intermittently spatter. Seismicity and deformation rates throughout the volcano remain at background levels.

Summit Observations:
The lava lake within the Halema’uma’u Overlook crater remains active. The depth to the lake was estimated at 26 m (85 ft) below the crater rim, measured last night. Tiltmeters at Kilauea’s summit recorded slightly decreased tilt. Seismicity is within normal, background rates with tremor fluctuations associated with lava lake spattering. The summit sulfur dioxide emission rate ranged from 580 to 3,200 metric tons/day measured yesterday.
kilauea

Pu’u ‘O’o Observations:
Webcam images over the past 24 hours show persistent glow at long-term sources within the crater. There were no significant changes in seismicity or tilt over the past 24 hours. The sulfur dioxide emission rate from all East Rift Zone vents on July 27 was about 290 metric tons/day.

kilauea

Lava Flow Observations:
The 61G lava flow extending southeast of Pu’u ‘O’o towards the coastal plain on Kilauea’s south flank remains active, with nearly all surface breakouts limited to the coastal plain. The Kamokuna area ocean entry continues and has widened since July 26. It now spans 240 m (787 ft) where it spills over the sea cliff. Areas of incandescence remain visible in overnight webcam views of the active lava flow field. There were virtually no active breakouts on the pali remaining, with nearly all activity limited to the coastal plain.

Kilauea

As a strong caution to visitors viewing the new ocean entry (location where lava meets the sea) for Flow 61G, there are additional significant hazards besides walking on uneven surfaces and around unstable, extremely steep sea cliffs. Venturing too close to an ocean entry exposes you to flying debris created by the explosive interaction between lava and water. Also, the new land created is unstable because it is built on unconsolidated lava fragments and sand. This loose material can easily be eroded away by surf causing the new land to become unsupported and slide into the sea. Finally, the interaction of lava with the ocean creates an acidic plume laden with fine volcanic particles that can irritate the skin, eyes, and lungs.

Source : HVO

Photos : Sean King , CJ Kale , HVO , David Ford.

Recommended Posts

Leave a Comment

Nous contacter

Nous ne sommes pas disponibles pour le moment. Mais vous pouvez nous envoyer un email a l'aide du formulaire ci-dessous.

Not readable? Change text. captcha txt

Start typing and press Enter to search