Geology, geography and global energy

Scientific and Technical Journal

Hydrogeochemical features of the complex post-salt brines Caspian syncline

2013. №4, pp. 96-101

Myazina Natalya G.  - C. Sc. in Geology and Mineralogy, Associate Professor, Orenburg State University, 13 Pobeda ave., Orenburg, 460018, Russian Federation,, geologia@mail.osu.ru

In the article the basic regularities of formation and placement of salt chloride brines Caspian syneclise. Given the characteristics of the main geochemical and genetic types of brines, considered their Genesis. Shows the chemical composition of the original brine on oil exploration areas. The most widely infiltrogennye brine leaching suprasalt sequences developed in the Mesozoic. At shallow on the domes, the dissolution of salts is sedimentogene chloride sea water supply and mass transfer occurs as a result of forced convection (filtering). With the depth decreases the rate of groundwater movement, the role of molecular diffusion mass transfer. It should also be noted in association with fractures of salt domes hydrogeochemical anomalies caused by the migration of fluids (groundwater, hydrocarbons) from the lower floors of the subsalt upper part of the section structures. In the post-salt sea floor in clastic and carbonate strata outside the zones of influence of salt domes (above mezhkupolnyh depressions) are sedimentogene chloride sodium waters and brines with mineralization up to 2–40 g/l of at least 70 g/l. In mezhkupolnyh depression with depths ranging from 1500 to 4416–4424 m at plastoispytanii oil wells from the Upper Permian, Triassic, Jurassic, Cretaceous derived small tributaries metamorphosed sedimentogene chloride sodium-calcium (calcium-sodium) brines Cl–Ca type III b (by E.V. Posokhova, V.A. Sulin). Gaza waters suprasalt deposits mainly nitrogen methane-nitrogen within the methane gas bearing structures with heavy hydrocarbons. The possibility of using the chloride brine as a source of hydro-and spa resources in the development of oil and gas fields. Extraction of valuable components from the water passing the most economical option.

Key words: Caspian sedimentary basin,chemical composition and salinity,chloride brines,major geochemical and genetic types: leaching and diffusion subsalt sedimentogennye brines

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