ご質問ありがとうございます。
全力回答します。
｛解説｝
まず「活火山」の定義です。
地質調査総合センターのウェブサイトによると、活火山とは
「概ね過去1万年以内に噴火した火山及び現在活発な噴気活動のある火山」
です。
VolcanoDiscovery というウェブサイトに、active volcano の定義が載っています。
【出典：VolcanoDiscovery】
An active volcano is a volcano that has had at least one eruption during the past 10,000 years. An active volcano might be erupting or dormant.
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↓
〈訳〉
active volcano とは、過去1万年以内に噴火した火山のこと。現在噴火している火山も含まれる。
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↑ほぼ同じですよね。
~~~~~~~~~~~~~~~
｛例｝
Japan's Mt Fuji is an active volcano.
日本の富士山は活火山である。
【出典：Stuff.co.nz-Sep 10, 2015】
Mount Etna is the largest active volcano in Italy.
エトナ火山はイタリア最大の活火山である。
【出典：LiveScience.com-Feb 25, 2013】
Mauna Loa is the largest active volcano on Earth.
マウナ・ロア山は、世界最大の活火山である。
【出典：Big Island Now-Jan 29, 2016】
お役に立てば幸いです。
ありがとうございました。
This means that the volcano is occurring/happening and volcanic material is been released.
Active Volcano
（活火山）
This means that the volcano is occurring/happening and volcanic material is been released.
火山活動している（噴火している）、火山灰や火山岩が噴出している状態のことを意味します。
It is a volcano that has had at least one eruption during the past 10 000 years
An active volcano might be erupting or dormant
erupting volcano is an active volcano that is having an eruption
dormant volcano is an active volcano that is not erupting, but supposed to erupt again
_________________________________________________________________
Examples of active volcanoes
Mount Vesuvius, Italy
Mount Adams in US (Washington)
Mount Mayon in Albay in the Philippines
Popocatepetl in Mexico
①Active Volcano＝活火山
It is a volcano that has had at least one eruption during the past 10,000 years.
(過去1万年の間に最低1回は噴火したことがある火山)
②Erupting volcano＝噴火している火山
Erupting volcano is an active volcano that is having an eruption.
(噴火している火山)
③Dormant volcano＝休火山
Dorman volcano is an active volcano that is not erupting but supposed to erupt again.
(噴火していない状態の活火山だが、また噴火する可能性がある火山)
Examples of active volcanoes:
(活火山例)
Mount Vesuvius (Italy)
ベェスビィオ山（イタリア）
Mount Adams (Washington, US)
アダムス山（アメリカ・ワシントン州）
Mount Mayon (Albay, Phillippines)
マヨン山（フィリピン）
Popocatepeti (Mexico)
ポポカテペトル山（メキシコ）
We watched in awe as the once dormant volcano, began to erupt!
An "active volcano "is a volcano that has had at least one eruption
during the past 10,000 years....(An active volcano might be erupting or dormant. )
A "dormant volcano" is an active volcano... that is not erupting;-)
PS
Dormant does not mean dead...and it may erupt again at sometime in the future.
An "active volcano" is a volcano that has had at least one eruption during the past 10,000 years. An active volcano might be erupting or "dormant". An erupting volcano is an active volcano that erupted. A dormant volcano is an active volcano that has not erupted but can erupt again. When a volcano erupts, hot lava bursts from it. Lava is a molten rock which is expelled in an eruption.
An active volcano is one which is currently erupting, frequently erupts, or recently erupted.
A dormant volcano is one which has the ability to erupt hut has not done so in a while.
An extinct volcano is one which no longer has the ability to erupt.
An active volcano is a volcano that has had at least one eruption during the past 10,000 years.
An active volcano might be erupting or dormant. An erupting volcano is an active volcano that is having an eruption...
A dormant volcano is an active volcano that is not erupting, but supposed to erupt again
こんにちは。
「活火山」は英語で active volcano と言います。
volcano が「火山」です。
【例】
Is this an active volcano?
「これは活火山ですか？」
Have you ever seen an active volcano?
「活火山を見たことがありますか？」
ぜひ参考にしてください。
An Active volcano is the term given to a volcano (a mountain in which hot lava and gases reside inside) that has the potential to erupt.
'Active' expresses the fact that something it alive and active.
A dormant volcano is the term that is given to a volcano which has not erupted for a very long time and is usually safe to be around.
'Dormant' usually used to express the fact that somethings actions have been slowed down or stopped for a long period of time.
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