Earthquakes at 2 Alaska Volcanoes Could Signal Eruption

In this photo provided by the Alaska Volcano Observatory/US Geological Survey is the Tanaga Volcano near Adak, Alaska, on May 23, 2021. (Alaska Volcano Observatory/US Geological Survey via AP)
In this photo provided by the Alaska Volcano Observatory/US Geological Survey is the Tanaga Volcano near Adak, Alaska, on May 23, 2021. (Alaska Volcano Observatory/US Geological Survey via AP)
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Earthquakes at 2 Alaska Volcanoes Could Signal Eruption

In this photo provided by the Alaska Volcano Observatory/US Geological Survey is the Tanaga Volcano near Adak, Alaska, on May 23, 2021. (Alaska Volcano Observatory/US Geological Survey via AP)
In this photo provided by the Alaska Volcano Observatory/US Geological Survey is the Tanaga Volcano near Adak, Alaska, on May 23, 2021. (Alaska Volcano Observatory/US Geological Survey via AP)

A second volcano in remote Alaska is experiencing elevated earthquake activity this week, signaling an increased potential for eruption, officials said.

Earthquake activity near Takawangha Volcano increased over the past 48 hours and are continuing, Alaska Volcano Observatory officials said in a news release Thursday.

That volcano is west of Anchorage in the western Aleutian islands and about 5 miles (8 kilometers) from Tanaga Volcano, which scientists said earlier this week had seen intensified earthquake activity.

The Alaska Volcano Observatory raised the alert level to advisory status for Tanaga Volcano late Tuesday after the quakes became vigorous.

The observatory on Thursday raised the alert level to watch status for Takawangha Volcano.

Analysts at the observatory continue to monitor the situation closely. Up to several earthquakes per minute are occurring under Tanaga Island, where both volcanoes are located, the observatory said. The largest quake over the previous 24 hours was a magnitude 3.9 located under Tanaga Volcano.

No eruptive activity or signs of unrest was detected in satellite or other monitoring data.

The island is about 1,250 miles (2,012 kilometers) southwest of Anchorage. There are no communities there, but Adak, a city of about 170 people on another island, is about 65 miles (105 kilometers) away and could see ashfall.

If one of the volcanoes were to erupt, it could be a problem for aircraft. The Aleutians are below the routes that jets fly between North America and Asia. Volcanic ash is angular and sharp and can cause airplane engines to shut down. Past eruptions had both ash clouds and viscous lava that moves slowly, much like what happened at Mount St. Helens in Washington state in 1980.

No historical eruptions are known from Takawangha but field work shows recent eruptions have occurred and its possible historic eruptions attributed to Tanaga may instead have come from Takawangha, according to scientists.

The last eruption from Tanaga Volcano was in 1914.



Latest Tests Show Seine Water Quality Was Substandard When Paris Mayor Took a Dip

 Boats carrying members of delegations sail along the Seine during the opening ceremony of the Paris 2024 Olympic Games on July 26, 2024. (AFP)
Boats carrying members of delegations sail along the Seine during the opening ceremony of the Paris 2024 Olympic Games on July 26, 2024. (AFP)
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Latest Tests Show Seine Water Quality Was Substandard When Paris Mayor Took a Dip

 Boats carrying members of delegations sail along the Seine during the opening ceremony of the Paris 2024 Olympic Games on July 26, 2024. (AFP)
Boats carrying members of delegations sail along the Seine during the opening ceremony of the Paris 2024 Olympic Games on July 26, 2024. (AFP)

Tests results released Friday showed the water quality in the River Seine was slightly below the standards needed to authorize swimming — just as the Paris Olympics start.

Heavy rain during the opening ceremony revived concerns over whether the long-polluted waterway will be clean enough to host swimming competitions, since water quality is deeply linked with the weather in the French capital.

Paris Mayor Anne Hidalgo took a highly publicized dip last week in a bid to ease fears. The Seine will be used for marathon swimming and triathlon.

Daily water quality tests measure levels of fecal bacteria known as E. coli.

Tests by monitoring group Eau de Paris show that at the Bras Marie, E. coli levels were then above the safe limit of 900 colony-forming units per 100 milliliters determined by European rules on June 17, when the mayor took a dip.

The site reached a value of 985 on the day the mayor swam with Paris 2024 chief Tony Estanguet and the top government official for the Paris region, Marc Guillaume, joined her, along with swimmers from local swimming clubs.

At two other measuring points further downstream, the results were below the threshold.

The statement by Paris City Hall and the prefecture of the Paris region noted that water quality last week was in line with European rules six days out of seven on the site which is to host the Olympic swimming competitions.

It noted that "the flow of the Seine is highly unstable due to regular rainfall episodes and remains more than twice the usual flow in summer," explaining fluctuating test results.

Swimming in the Seine has been banned for over a century. Since 2015, organizers have invested $1.5 billion to prepare the Seine for the Olympics and to ensure Parisians have a cleaner river after the Games. The plan included constructing a giant underground water storage basin in central Paris, renovating sewer infrastructure, and upgrading wastewater treatment plants.