One of the '70s' greatest hard-rock obscurities turns 40 today. And if you missed out on it back then, prepare to have your mind blown by the sheer, seismic power of the aptly named 'Volcanic Rock' by the Australian quartet Buffalo.

In early 1973, with AC/DC not quite formed yet, what few Aussie-bred hard-rock bands were already up and running (like blues heavies Billy Thorpe and the Aztecs or psychedelic warriors Kahvas Jute, featuring future Rainbow bassist Bob Daisley) were hardly able to challenge international heavyweights like Led Zeppelin, Black Sabbath and Deep Purple.

That's why the visionary violence perpetrated by Buffalo's second LP was such a stunning creative breakthrough, even if it proved a tad too hard to swallow for most mainstream consumers. ‘Volcanic Rock’ was even miles removed from Buffalo's mostly unfocused and prog- and psych-influenced debut, 'Dead Forever ... ,' released the previous year.

By streamlining their lineup (pared down from six to a classic quartet), Buffalo also streamlined their sound -- not by completely abandoning the musical wanderlust and post-Aquarius lyrics showcased on mesmerizing jams like 'Freedom' and 'The Prophet,' but honing them with much better hooks provided by gravelly soul-influenced singer Dave Tice and versatile guitarist John Baxter.

Baxter is the true star of, and instigator behind, 'Volcanic Rock,' beginning with his blistering leads that launch album opener 'Sunrise (Come My Way),' which shares as much DNA with the MC5 as it does with Blue Cheer and Black Sabbath. Not surprisingly, the song has since been shamelessly cannibalized for its parts by more stoner-rock bands than you can shake a bong at.

Mid-album sandwich meat like 'Till My Death' and 'Pound of Flesh' tone things down a notch with solid blues-rock fundamentals rooted in the rhythm section of bassist Pete Wells (later of Rose Tattoo) and drummer Jimmy Economu. But bruising proto-metal debauchery is duly reinstated by the album's closing stunner, 'Shylock,' which basks in equal doses of ominous melodies and pulverizing riffs -- all conjured by the mad six-string magician Baxter.

We also must note 'Volcanic Rock''s controversial (and vertical) gatefold cover painting, which depicts a Promethean figure perched atop a curiously proportioned volcano while hoisting aloft what appears to be ... a flaccid penis? All this was rendered in artistic, but still graphic, detail.

Needless to say, this too curbed Buffalo’s chances of seeing the album properly promoted in record stores, and further contributed to their disappointing sales. Not that Australia -- or the world, for that matter -- were ready for the Sydney foursome. But you have to admit that both the artwork and music exemplifies Buffalo's erupting sound to perfection.

Hear Buffalo's 'Volcanic Rock'

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