This year’s SEG Conference was held in Turkey with the theme “Tethyan Tectonics and Metallogeny”. To this end I was invited to give an overview of the prospectivity, discovery history and performance of the Tethyan Belt.
For those who are not familiar, the Tethyan Belt (TB) extends across 2 continents and 33 countries – from France in the West to Thailand in the West. To keep things manageable I consolidated the 33 countries into the following 6 regions along the belt; Western Europe, Eastern Europe, Asia Minor, Central Asia & Middle East, Himalayas and South East Asia
- Expenditures in the TB have grown substantially since the early 2000s, peaking at $755m (in 2015 US Dollars) in 2012.
- Over the last decade $4.7 billion was spent on exploration in the Belt – equal to 3.2% of global exploration expenditures on non-bulk minerals
- Over half of the spend was in Eastern Europe and Asia Minor and the two main targets are gold and copper
- Over the last 50 years, 246 significant deposits have been found in the TB and industry continues to find ~5-8 new deposits each year. Gold and copper accounted for 81% of the discoveries
- Over the last decade 52 deposits were found, equal to 8.2% of all deposits found in the World.
- The average cost per discovery in the TB is currently running at $158 million per deposit -which is 2/3rds that the World average (of $236m)
- Over the last decade the average discovery cost in the TB was $29/oz (versus $49/oz for the World). Within the TB the discovery cost varied from $18/oz in Asia Minor to $138/oz in SE Asia
- The corresponding discovery costs for copper was 3.0 cents/lb (versus 3.6 c/lb for the World). Within the TB the discovery cost varied from 1.6 c/lb in the Himalayas to 13.4 c/lb in SE Asia
- The estimated value of these discoveries was $4.1 billion. On this basis the Value/Cost Ratio (or “Bang per Buck”) was 0.87. For comparison, the average for the World over the same time period was 0.65.. While this suggests that exploration is destroying value, in practice the returns should improve over time as more (unreported) discoveries are identified and as known deposits are drilled-out (and grow in size). It should also be noted that the Returns vary by Region along the Belt – from 0.33 in Central Asia & Middle East to 1.30 in the Himalayas
In conclusion, the Tethyan Belt is fertile for gold and base metals. To date, much of it is under-explored and is ripe for significant major new discoveries. All it needs is a brave/smart geologist with the right tools to unlock the treasure.