Human Interaction with the Rock
Tara Lead and Zinc Mines
Learning Outcome
 Identify the ways humans use rocks in Tara
 Discuss the impact this has on the Rock Cycle
Mining in Ireland
• Important economic activity
• Employs 6000 people
• Generates over 1 billion euro annually
Widely used
60% of all lead is used in lead acid batteries
Has many other uses;
– Plumbing
– X-ray gowns
– Ammunition
– TV & Computer screens (blocks radiation)
• Galvanising steel (prevents rust)
• Zinc dust & compounds used in;
– Cosmetics
– Plastics
– Paints
– Ink
Tara Mines
• Navan, Co Meath
Formation of Lead & Zinc
• Rock containing metal is called ore
• Carboniferous limestone
• Formation of ore linked to movement of groundwater
through the rock
• Seawater seeped into the rock
• This was heated by geothermal energy from inside
• As the hot seawater (brine) moved through the planes
and joints, it dissolved small amounts of lead and zinc
out of the rocks
• The rich layers of ores within the rocks are called veins
Human Interaction with Rock Cycle in
Construct shaft mines
Extract ore
Disposal of waste products
Transport systems
General Info
Shaft Mine
Europes largest zinc mine
5th largest zinc mine in the world
Uses state of the art, remote control
technology and computerised systems
• Local economy in Navan has benefitted
• 700 Jobs
– Chemists
– Environmental Scientists
– Miners
– Geologists
Mining in Tara
• Output transported to Norway, Finland &
other European countries
• Lead and zinc ores formed in faulted
limestone in Navan, over 350 million years ago
• Lie 50 – 900 metres below the surface
• Stope and Pillar
• Large areas (stopes) blasted out and pillars left
standing to support them
• Modern computerised machinery used to
bring the ore to the surface
On the Surface
Rock crushed into powder
Chemically treated
Dried to form metal concentrate
Then transported to Dublin Port
Further process details
• Water used is recirculated and reused
• Sediment is extracted and stored
• Backfill may be needed in the stopes, cement
and water pumped through the boreholes
Process Mill
Operates continously
12 hour shifts
Highly computerised
On-site laboratory –analysis tests on rock
Environmental Protection
Landscaping to reduce visual impact
Wetland areas to treat water
Sheep grazing areas
Noise and Dust levels constantly monitored
Regular reports to the EPA
Spin-Off Effects
• For every one job in Tara, three indirect jobs
are supported.
– Eg; Caterers, Accountants, Truck Drivers, Safety
Consultants, Metallurgists
• 2009; Threatened with closure
– Demand for zinc to galvanise car bodies fell
• However continued demand for zinc from
China and India
• Mine life extends past 2015
Environmental Protection
Exam Question
• ‘People interact with the rock cycle in various
ways.’ Examine this statement using an
example you have studied.

Human Interaction with the Rock Cycle