The Resource Potential and Development Prospect of Helium in Changqing Gas Field

Table 1

Industrial standards for helium-bearing gas fields [20].

Helium reserves (10^6 m^3)	Size classification	Helium content (volume %)	Content classification
≥100	Ultralarge gas field	≥0.500	Field extremely rich in helium
50-100	Large gas field	0.150-0.500	Helium-rich field
25-50	Middle gas field	0.050-0.150	Helium-bearing field
5-25	Small gas field	0.005-0.050	Helium-lean field
< 5	Ultrasmall gas field	< 0.005	Field extremely lean in helium