New images from Landsat 8 from 11th December

Landsat 8 image of Saunders Island from the 11th December shows a gas plume originating from Mount Michael Volcano.

Gas emission originating from Mount Michael Volcano. SOURCE: Landsat 8/USGS/NASA.

In the Landsat 8 image of Bristol Island, the summit area of Mount Sourabaya is exposed in a largely cloudy image showing what appears to be a minor steam emission. In the thermal image a thermal anomaly is visible from the same area. This suggests some possible fumarolic activity.

Minor steam emission on Mount Sourabaya Volcano. SOURCE: Landsat 8/USGS/NASA.

Thermal anomaly on the summit area of Mount Sourabaya. SOURCE: Landsat 8/USGS/NASA.

Zavodovski Island catch ups December 2016

I have another catch up post, this time about Zavodovski Island. While on various days a white plume originating from Mount Curry was visible in satellite imagery, the images from 19th and 20th November and the 6th December stood out for me. Especially as it looks like there was some possible ash content in the November plumes.

Emission on 19th November 2016. SOURCE: Aqua/MODIS/NASA.

Possible emission on 20th November 2016. SOURCE: Aqua/MODIS/NASA.

Emission on 6th December 2016. SOURCE: Aqua/MODIS/NASA.

Saunders Island catch ups December 2016

As I was busy at the time I wasn't able to get round to this post sooner, but a thermal anomaly was detected on Saunders Island at times indicating that some sort of activity on Mount Michael Volcano went on since November. According to data on the MODVOLC website, a thermal anomaly was detected on Mount Michael during the days 3rd, 20th, 21st, and 24th November and most recently, on the 17th December.

Most recent hotspot detection on Saunders Island as of 17th December. SOURCE: MODVOLC.

Two emissions: Saunders Island and Zavodovski Island 17/12/16

On 17th December 2016, two plumes appear in satellite images. One originating from Zavodovski Island, and the other from Saunders Island.

In the image of Zavodovski Island, a white plume originating from the summit crater of Mount Curry is seen drifting in a south-southwesterly direction before dispersing. It's more likely to be a gas plume although I wouldn't rule out the possibility of some slight ash content.

A plume originating from Mount Curry on Zavodovski Island is drifting then dispersing to the south-southwest. SOURCE: Terra/MODIS/NASA.

In the image of Saunders Island, a greyish plume originating from the summit crater of Mount Michael is seen drifting towards the northeast. A thermal anomaly was also detected on the summit area of Mount Michael. This indicates that it's likely to be an eruption occurring on Mount Michael Volcano.

What is likely to be an ash plume from Mount Michael on Saunders Island. SOURCE: Aqua/MODIS/NASA.

Ash emission on Zavodovski Island

An ash plume originating from Zavodovski Island is visible in a satellite image from 9th December. The ash plume is seen drifting south-southwest but judging from the image it doesn't look like that it's originating from the summit crater of Mount Curry, but from the Asphyxia Plain area of the island. So we could be looking at a possible flank eruption. As the plume is greyish in colour, in my opinion that's what gives it away.

Possible flank eruption on Zavodovski Island on the 9th December 2016. SOURCE: Aqua/MODIS/NASA.

Gas emissions continue on Zavodovski

Plumes drifting from Mount Curry on Zavodovski Island continue to be visible in satellite images during various days. It's likely that they are gas emissions although I wouldn't rule out the possibility of the odd plume having some slight ash content in it.

Zavodovski as of 1st November 2016 emitting a gas plume with some possible slight ash content. SOURCE: Terra/MODIS/NASA.

Gas emissions on Zavodovski

Between 17th September to 10th October 2016, satellite images picked up a gas plume during various days drifting from Zavodovski Island. Here is an example image below.

Gas plume from Zavodovski on the 3rd October 2016. SOURCE: Aqua/MODIS/NASA.

Suspected ash plume from Saunders Island

In the satellite image from 14th September 2016, a faint dirty looking plume which appears to be originating from Mount Michael is present drifting northeast. This could possibly be an ash plume dispersing, or just simply a gas emission but I'm not 100% sure.

What appears to be a possible dispersing ash plume from Saunders Island on 14th September 2016. SOURCE: Terra/MODIS/NASA.

Clear image at last of Bristol Island and also Saunders Island

Clear images of the South Sandwich Islands from the 21st August 2016 have been released on the EOSDA website, and because it shows a clear view of the islands I was able to truly observe the changes on Bristol Island and I also discovered a thermal anomaly inside the crater of Mount Michael on Saunders Island.

First of all, in the image of Bristol Island a lava field is visible extending towards the west and north-northwest of Mount Sourabaya. The western part looks like it was starting to get frozen over while the north-northwest part of the lava field looks more darker. A steam emission originating from the crater of Mount Sourabaya is also visible. Although the lava appears to retain heat, it is not easy to truly tell whether the eruption has ended all together or if it's still in the last effusive stages.

Clear image view showing the new lava field on Bristol Island. SOURCE: Landsat Viewer/EOS Data Analytics.

Close up view of the new lava field on Bristol Island. SOURCE: Landsat Viewer/EOS Data Analytics.

Meanwhile in the infrared image of Saunders Island, a thermal hotspot is visible inside the summit crater of Mount Michael. This could either mean some low level eruptive activity is taking place, or there's simply high temperatures present inside the crater.

Infrared image of Saunders Island showing thermal anomaly inside the crater of Michael Volcano. SOURCE: Landsat Viewer/EOS Data Analytics.

Possible eruption on Zavodovski

It appears an eruption may have occurred yesterday on Zavodovski Island's Mount Curry volcano. If you look at the satellite image from 29th August 2016 you will notice a plume originating from Mount Curry and drifting in a east-northeasterly direction, and has a little greyish colour in it. In my view, it's likely to be an eruption plume or at least an ash and gas emission.

What looks to be a possible eruption on Mount Curry as of 29th August 2016. SOURCE: Suomi NPP/VIIRS/NASA.

Activity update 22/8/16: Bristol Island, Saunders Island

The eruption of Mount Sourabaya on Bristol Island appears to have ended or at least is in it's dying stages. A hazy Landsat 8 image from 21st August 2016 shows nothing more than dark patches with a little bit of steaming (indicating lava flows) and a thermal image revealed that the thermal anomaly over the lava field area wasn't so strong. This could indicate that the eruption of Mount Sourabaya has either ceased or may be in it's dying stages. A faint thermal anomaly is also present inside another crater to the east of Mount Sourabaya indicating possible elevated ground temperatures.

Satellite image of Bristol Island on the 21st August. SOURCE: Landsat 8/USGS/NASA.

Thermal image of Bristol Island on the 21st August. Has the eruption ceased? SOURCE: Landsat 8/USGS/NASA.

Meanwhile over on Saunders Island, a Landsat 8 image from the 21st August 2016 shows a steam plume being emitted from the summit crater of Mount Michael and drifting in a northerly direction. There's also what appears to show an enlargement of the crater caused by the collapse of an area between the summit crater and the "Old Crater" resulting in what possibly looks to be the two craters merging into one.

Saunders Island on the 21st August. SOURCE: Landsat 8/USGS/NASA.

Two Strong earthquakes hit South Georgia/South Sandwich Islands region

In the space of 2 days, two strong earthquakes over the magnitude of 6 has hit an area to the northwest of the East Scotia Ridge between South Georgia Island and the South Sandwich Islands. The first quake struck with a magnitude of 7.4 on the 19th August 2016 at 07:32 UTC with a depth of 10km, and then on the 21st August 2016 a second quake struck the same area with a magnitude of 6.4 at 03:45 UTC also with a depth of 10km.

7.4 magnitude earthquake on 19th August 2016. SOURCE: USGS.

6.4 magnitude earthquake on 21st August 2016. SOURCE: USGS.

Bristol Island update 3/8/16

Satellite images of Bristol Island from recent days did not show an ash plume but on the Landsat Viewer on the EOS Data Analytics website an infrared image from the 29th July 2016 reveals an active lava flow descending the northwest flank of Mount Sourabaya with a steam plume also being present. This is an indicator that the activity which began in late April 2016 continues. 

Because the island is partially covered in clouds it is difficult to observe the changes on the landscape.

Activity continues on Mount Sourabaya. SOURCE: Landsat Viewer/EOS Data Analytics.

Active lava flow evident on Infrared imagery. SOURCE: Landsat Viewer/EOS Data Analytics.

Bristol Island update 19/7/16

Satellite image from the 19th July 2016 shows a clear view of Bristol Island which appears to be grey in colour on the eastern half of the island. This could either be ashfall from the eruption of Mount Sourabaya or that the snow and ice has melted. An ash plume originating from Mount Sourabaya is visible drifting east-northeast. Also visible in the image are two short dark strips extending west and northwest respectively from the Mount Sourabaya area indicating lava flows.

Eastern half of Bristol Island appears grey in the image from 19th July 2016. SOURCE: Terra/MODIS/NASA.

Bristol Island update 17/7/16

Since my last post (dated 18th June 2016) an ash plume or a plume with ash content originating from Bristol Island was visible in satellite images from various days, the most recent being on the 16th July 2016. During other days, sometimes the plume was white in colour and sometimes cloud cover prevented observations.

In my view:
a) The eruption which began during late April 2016 continues.
b) The volcano is going through a different eruptive phase consisting of continuous explosive eruptions.
c) A new eruption might be occurring although I think it's most likely one of the above two scenarios.

Ash emission on Bristol Island 16th July 2016. SOURCE: Suomi NPP/VIIRS/NASA.

Activity update 18/6/16: Bristol Island, Zavodovski Island

Satellite images from the 7th and 15th June shows that the eruption on Mount Sourabaya on Bristol Island persists. The ash emissions however seems to have diminished suggesting that the intensity of the eruption has reduced.

Meanwhile on Zavodovski Island a gas plume was visible in satellite images from various days since 8th June 2016.

Bristol Island (bottom left) continues to emit an ash plume on 7th June 2016. SOURCE: Suomi NPP/VIIRS/NASA.

Ash emissions continue on 15th June 2016. SOURCE: Aqua/MODIS/NASA.

Gas plume originating from Zavodovski Island on 13th June 2016. SOURCE: Terra/MODIS/NASA.

Bristol Island update 4/6/16

This is going to be a very quick post but the eruption continues on Bristol Island and the satellite image from 4th June 2016 clearly shows an ash plume drifting east indicating that the intensity of the eruption persists.

Ash plume drifts east on 4th June 2016. SOURCE: Suomi NPP/VIIRS/NASA.

Activity update 2/6/16: Bristol Island, Zavodovski Island, Saunders Island

Satellite images from the 31st May and 1st June 2016 shows that an ash plume originating from Bristol Island is clearly evident and is drifting for a considerable distance in a northeasterly direction. Bristol Island however is not the only place displaying some form of volcanic activity, Mount Curry on Zavodovski Island has been emitting a gas plume also drifting for a considerable distance in a northeasterly direction on the same days.

Ash plume from Bristol Island more evident plus gas emission from Zavodovski Island is present in the image from 1st June 2016. SOURCE: Aqua/MODIS/NASA.

In an image from the 28th May 2016, a faintly dark line appears to be originating from Mount Michael on Saunders Island indicating a possible minor ash emission.

Possible ash emission on Saunders Island 28th May?. SOURCE: Terra/MODIS/NASA.

Bristol Island update 30/5/16

Satellite image from the 26th May 2016 shows some faintly dark lines on Bristol Island suggesting the presence of lava flows and also a dark patch just west-northwest of the Mount Sourabaya area. The dark patch suggests the possibility that a new cinder cone vent may have formed or it could simply be an accumulation of lava.

Image from the 28th May 2016 shows an ash plume drifting northeast and again on the 29th May 2016 only this time it's drifting north-northeast. This could suggest that the activity may have intensified.

On the MODVOLC website a hotspot was detected during most days in May on Bristol island.

Bristol Island on 26th May 2016. SOURCE: Aqua/MODIS/NASA.

Ash plume drifts northeast from Bristol Island on 28th May 2016. SOURCE: Terra/MODIS/NASA.

Ash plume from Bristol Island (bottom centre-left) drifting NNE on 29th May 2016. SOURCE: Suomi NPP/VIIRS/NASA.

Most recent hotspot detection on Bristol Island. SOURCE: MODVOLC.

7.2 magnitude earthquake in South Sandwich Islands

A strong magnitude 7.2 earthquake has hit the South Sandwich Islands on the 28th May 2016. The epicenter of the quake was reported to be about 58km north-northeast of Visokoi Island with a depth of 72.7km (45.2 miles).

Earthquake 28th May 2016. SOURCE: USGS.

Bristol Island update 21/5/16

Nothing really shows up in the satellite image from 17th May 2016 due to cloudy conditions although incandescence is still present over Sourabaya Volcano on Bristol Island suggesting that the eruption is still continuing. Otherwise nothing else could be determined.

Incandescence is still visible despite cloudy conditions. SOURCE: Landsat 8/USGS/NASA.

Bristol Island update 13/5/16

New image from 13th May 2016 shows a plume is still present and drifting northeast indicating that the eruption on Mount Sourabaya continues. A little dark area is also present at the centre-left of the island indicating possible lava activity.

Eruption continues in the image from 13th May 2016. SOURCE: Terra/MODIS/NASA.

Eruption continues on Bristol Island

The satellite image from 10th May 2016 shows a hazy but cloudy sky although Bristol Island is barely visible in the image. Incandescence is still present at the Sourabaya Volcano area as well as a plume which is drifting NE, this indicates that the eruption continues. If you look closely at the area of incandescence you will find that it seems to be faintly elongated which indicates that a lava flow may be occurring. If it is not lava then it may simply be a reflection of the incandescence on the clouds. We can only truly know once we see a cloud free image of the island in the near future.

Incandescence indicates that the eruption is continuing on Sourabaya Volcano. SOURCE: Landsat 8/USGS/NASA.

While I was away...

Between 20th March and 11th April I was away on holiday in Ecuador and the Galapagos Islands so I just needed to catch up with a couple of findings on satellite images.

We start first with Saunders Island and in the image from 28th March 2016 a dark area is present on the summit area of Mount Michael, but in other images from various days a gas emission seems to be drifting from Mount Michael.

Dark spot shows up on Mount Michael on the 28th March 2016. SOURCE: Terra/MODIS/NASA.

What appears to be a gas emission from Mount Michael on the 11th April 2016. SOURCE: Terra/MODIS/NASA.

On Zavodovski Island a narrow plume is seen drifting ENE in an image from 30th March indicating that a possible minor ash emission may have occurred. An image from 7th April again shows a narrow plume drifting east but only travelling a shorter distance.

An emission from Zavodovski on the 30th March 2016 which may have contained ash. SOURCE: Suomi/VIIRS/NASA.

Again on 7th April 2016 a plume with suspected ash content. SOURCE: Terra/MODIS/NASA.

Eruption on Bristol Island!

The Landsat 8 satellite images from the 24th April and 1st May 2016 show that an eruption is occurring on the Mount Sourabaya Volcano on Bristol Island. Incandescence is clearly present in the crater area on Mount Sourabaya. A strong whitish plume originating from the crater shows up on the image from 24th April but in the image from 1st May, the whitish plume had diminished but is still present.

In my view, I am convinced that this is an eruption and is of strombolian style. Incandescence in the crater looks fairly intensive. I estimate the eruption to have begun around 19-23 April but could be possible to have started earlier. The last recorded eruption on Bristol Island came in 1956 in an area between Turmoil Point and Mount Sourabaya.

What shows a likely strombolian activity on Mount Sourabaya. SOURCE: Landsat 8/USGS/NASA.

Activity continues as of 1st May 2016. SOURCE: Landsat 8/USGS/NASA.

Dark spot on Saunders Island in February

In a satellite image from 20th February 2016, a dark spot appears on Saunders Island which indicates that recent activity of some kind had taken place. This could be that Mount Michael had been going through an eruptive phase, or it could simply be elevated ground temperatures volcanic in origin.

Dark spot which appears on Mount Michael on 20th February. SOURCE: Aqua/MODIS/NASA.

Dark patch on Saunders Island likely not activity?

Satellite image from 1st January 2016 shows a clear view of Saunders Island except for the summit area which was shrouded in clouds. It appears that the dark patch on the eastern side of the island is not linked to volcanic activity at all but rather that the snow and ice melted. When I checked out the Landsat 8 images of the other islands in the South Sandwich archipelago it turned out that they also have places which are devoid of snow and ice, the explanation for this is because it's summer down in the southern hemisphere while up in the northern hemisphere it is the opposite, winter. Because the summit area of Michael Volcano was shrouded in clouds in the image, it's not possible to determine what happened at the "Old Crater".

New Year's Day on Saunders Island. SOURCE: Landsat 8/USGS/NASA.