Study of Diagenesis and Pore Evolution of Triassic Jialingjiang Formation in Southern Puguang Gasfield

Table 2

Relationship between carbon and oxygen isotopic and sedimentary environment.

	Grain; dolomite	Dolomicrite	Gypsodolomite	Calcite; dolomite	Gypsum limestone
^13C (PDB, )	1.02	1.91	2.25	1.59	2.58
^18O (PDB, )	−3.92	−4.2	−3.6	−4.67	−4.62
Depositional environment	Intertidal flat	Tidal flat	Tidal flat	Tidal flat	Tidal flat
Dolomitization	Mixed water	Seepage reflux	Evaporating pumping