Characteristics and Geological Significances of Fluid Inclusions of Halite in Dongying Sag, East China

摘要

Dongying Sag is a secondary tectonic unit ofrnJiyang depression, located in the southeast ofrnJiyang depression in Bohai Bay Basin, China. It’s arntypical half-graben fault basin of Mesozoic-rnCenozoic eastern China. There are developed threernpositive structural belts: northern steep-slope,rnsouthern gentle-slope and central uplift. And theyrndivide Dongying sag into four subsags: Lijin,rnMinfeng, Niuzhuang and Boxing (Wu et al., 2013).rnAccording to core and logging analysis, there arernfour sets of salt rock, distributed in Ek1s, ES4xs, ES4xxand ES4rns from the bottom up (Xu et al., 2008).rnLaterally, salt rock beds are wide-spreading inrnMinfeng subsag, central uplift, Niuzhuang subsagrnand Binnan-Lijin areas, especially central uplift tornthe north where salt rock beds are concentratedrndeveloped on a large scale and formed twornthickness centers, Fengshen2 and Haoke1-rnDongfeng5 (hereinafter referred to as FS2, HK1rnand DF5). On the basis of present researchrnsituations of salt rock in Dongying Sag, achievementsrngave priority to salt rock sedimentology, structuresrnrelated to salt, the sealing property of salt rockrnand so on, however, lacked the study of salt-relatedrnfluid processes. Therefore, this paper gives detailedrnresearches about the characteristics of fluid inclusionsrnin halite of Dongying Sag for the first time,rnmakes a primary study on the relevant geologicalrnsignificances of different types of fluid inclusions,rnand establishes the foundation for the furtherrnresearches of salt-related fluid processes in future.