COMPARISON OF POST‐SEDIMENTARY ALTERATIONS OF OIL‐, GAS‐ AND WATER‐BEARING ROCKS

摘要: SUMMARY One of the productive horizons (17th) north Sakhalin has been studied. The areas within and beyond oil gas pools, near top at flanks structures were compared with where horizon under study was waterbearing. rocks least transformed by secondary processes accumulations, a sudden increase observed in content feldspars accessory minerals (epidote, ilmenite sphene) which had not undergone intrastratal solution. Inside however, no deceleration epigenesis observed. This points to more recent (post-Pliocene) accumulation gas, whereas first migration these Miocene strata occurred Upper Pliocene, according hampered epigenesis.