全北美洲(包括阿拉斯加)有數千座溫泉。其中有許多是在二千萬到四千五百萬年前,由於激烈的火山運動而形成的。這些溫泉的規模從最小的小泉到接近間歇泉;從像加州橋港北方Fales Hot Ditch的小泉到亞利桑那州Tonopah(英语:Tonopah)的地下湖(它曾經給在托诺帕营业的至少七座溫泉浴場提供了天然礦泉水,有兩座這樣的溫泉浴場的遺跡現在依然可以看得到)。
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