The Speculators: Stories of Western Tasmania (Part Two)

Introduction
It might be said that speculation; to form a theory (or hypothesis) without firm evidence, is the foundation of science. 
It may equally be said that speculation; to invest with a hope of gain but with the risk of loss, is the foundation of business.
The Dreamtime is speculation, as are the stories of the Bible, Torah and Quran.  Trade and agriculture are speculation.  Migration, mining, commerce and interplanetary travel are all speculation.
Raising a family is speculation.
Speculation leads to discovery, enlightenment and prosperity; but also to contempt and failure.
Stories of speculation are perpetual and unbounded.  This place is rich in them.
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​The Origins of Earth
The peaks upon which Gould bestowed the names of the great 19th Century men of science are old – even in the brain-bending time scales of geology.  And yet, as old as those mountains are, the rocks from which they are formed are known to exceed the age of the mountains by at least a factor of two.
Some humans, themselves in an advanced position on the human timeline, may recall driving to Queenstown along roads of a curious pink colouration.  The rocks crushed to construct those roads, and which gave the roads their distinctive colour, are believed to have been formed during the Ectasian Period, over 1200 million years ago (or, as one geologist described the period: bang in the middle of the “boring billion”).  Indeed, those rocks are so old, and so inconsistent with most other rocks of continental Australia, to lead to conjecture that, in those early days of world geology, significant portions of what now forms the basis of western Tasmania was in fact linked to an area of ancient North America.
Then, 500 million years ago, the Early Cambrian tectonic plates began to agitate and to catch against each other like old and very badly shuffled playing cards, resulting in a significant mountain-building event known as the Tyennan Orogeny.  This was, effectively, the geological equivalent of a multi-car crash on a busy roundabout - except the impact which caused this particular pile up occurred over a period of approximately 60 million years.  Firstly, in the Early Cambrian, an oceanic plate pushed up against eastern Australia, shuffling a layer of oceanic crust over the existing Precambrian rock base.  The resulting massive forces created a volcanic subduction zone, and shifted the base beds of Tasmania to the west and south.
Continuing tectonic plate pressure from the north resulted in a north-south compression of the oceanic base beds of the newly formed region we now know as Tasmania, and a corresponding east-west extension.  The extension, or spreading, of submarine plates can result in an event which geologists call a back-arc basin.  In this case, the location of the back-arc basin was below the western margin of the island we now call Tasmania.  The resultant north-south trough of about several hundred kilometres, which formed along the basin, is known as the Dundas Trough. 
Over time, seawater in the unconsolidated and rapidly filling volcanic basin had access to metals in the volcanic “pile” and also access to heat.  The seawater in the basin sunk, engaged with the the metals, heated, and rose to the newly formed sea floor where it spewed out mostly as seafloor volcanoes, called fumaroles.  In this way, the Dundas Trough filled with masses of diverse volcanic material which then became mineralised by circulating fluids.  This build up of diverse mineralisation in the Dundas Trough is known by geologists as the Mount Read Volcanics.
During the Middle-Late Cambrian, ongoing plate movement associated with the Tyennan Orogeny created further uplift of the original sediments, and also the newer, mineral rich deposits from the Dundas Trough, thrusting those deposits and the pink-hued conglomerate upwards into the beginnings of the terrain which Gould much later named after the 19th Century scientists, theologians and philosophers.
The results of the Tyennan Orogeny, 60 million years’ worth of pressure, eruption, obduction, sedimentation, folding, inversion, compression, extension, erosion, and re-folding, resulted in a complex and diverse geology, and the placement along the West Coast of Tasmania of substantial deposits of minerals and ores which would later become the catalyst for great human endeavour and enterprise.