GAS GAS GAS .. Conventional and Non Conventional.

I am often asked by people who are attempting to learn about GAS in our country just what is the difference between Conventional and Non Conventional Gas and so here is todays post regarding this.
 
Conventional gas
Conventional gas is obtained from reservoirs that largely consist of porous sandstone formations capped by impermeable rock, with the gas trapped by buoyancy. The gas can move to the surface through the gas wells without the need to pump.

Csg extraction at Gloucester at Tiedimans lane Forbesdale

Unconventional gas
Unconventional gas is generally produced from complex geological systems that prevent or significantly limit the migration of gas and require innovative technological solutions for extraction.

The difference between conventional and unconventional gas is the geology of the reservoirs from which they are produced.

There are several types of unconventional gas such as CSG, shale gas and tight gas.

Coal Seam Gas
CSG is entirely adsorbed into the coal matrix. Movement of CSG to the surface through gas wells normally requires extraction of formation water from the coal cleats and fractures. This reduces the pressure, allowing methane to be released from the coal matrix. Over time, water production decreases and gas production increases. CSG production normally requires a higher density of wells than conventional gas production; however CSG wells are typically shallower than conventional wells and cost much less to drill.

Shale gas
Shale gas is generally extracted from a clay-rich sedimentary rock which has naturally low permeability. The gas it contains is either adsorbed (i.e., closely to the surface matrix of the organic matter) or in a free state in the pores of the rock.

Tight gas
Tight gas is trapped in ultra-compact reservoirs characterised by very low porosity and permeability. The rock pores that contain the gas are minuscule, and the interconnections between them are so limited that the gas can only migrate through it with great difficulty.

"My personal view on this is very different to that of our leaders and a lot of other ordinary Australians who in my personal opinion trust to easily.  Trusting a crooked government is a recipe for disaster and our country is on the BRINK OF DISASTER from the unconventional gas extraction that is going on right now,  Minister Burke has just introduced more legislation to protect this rogue industry."   Mary-Ellen xx 

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