What is coalbed methane (CBM)?

• CBM is an environmental friendly clean fuel with properties similar to natural gas.
  
   
• Coal serves as both the source as well as the reservoir rock for CBM.
  
   
• CBM is generated within the coal seams during the ‘coalification’ process and stored in the coal seams in the adsorbed stage on the internal surface of coal matrix.
   

What are favourable geological factors for Development of CBM?

 

• Thick, laterally continuous coals of high thermal maturity (high volatile bituminous coal).
  
   
• Higher permeability of coal.
  
   
• High gas content of coal seam.
  
   
• Sizeable in place coal reserves.

What is life cycle of a CBM project?

• Exploration/Acquisition Phase(Phase-I):
  
   
  1. Identify, evaluate and acquire acreage.
     
      
  2. Obtain critical core data (gas content and saturation).
     
      
• Pilot Phase(Phase-II):
  
   
1. Drill and test pilot wells.
   
    
2. Expand as needed from central dewatering point.
   
    
• Full-Field Devlopment(Phase-III).
  
   
• Production(Phase-IV).
  
   
• Enhanced Recovery via N2 or CO2 Injection.

• Gas had migrated to reservoir trap.

• Immediate gas flow to well bore.
  
   
• Few wells to develop.
  
   
• Gas / water ratio decreases.
  
   
• Permeability not depth dependent.
  
   
• Can evaluate with well logs.
  
   
• May fracture to stimulate.
  
  

  CBM: 

• Coal is it’s own source rock.
  
   
• Gas diffuses slowly to cleat system then flows.
  
   
• Multiple wells and facilities to develop.
  
   
• Gas / water ratio increases.
  
   
• Permeability decreases with depth (2000m).
  
   
• Need cores / samples to fully evaluate - logs not enough.
  
   
• Always fracture to stimulate.

What is Commercial Discovery?
 

"Commercial Discovery” means a Discovery of Petroleum reserves which has been declared as a Commercial Discovery in accordance with the provisions of Articles 10 and/ or Articles 21.
 

What is Commercial Production?

“Commercial Production” means production of Crude Oil or Condensate or Natural Gas or any combination of these form the Contract Area (excluding production for testing purposes) and delivery of the same at the relevant Delivery Point under a programme of regular production and sale.