| Laizhou Bay area is a typical area of seawater intrusion studies. Seawater intrusion in theregion began in the late1970s, and it not only destroyed the local groundwater resources, butalso triggered a series of eco-environmental geological problems and seriously affected thelocal economy. The study is established by Laizhou Bay Changyi-Liutuan basic monitoringtypical profile. Through seawater intrusion during hydro geochemical research, combinedwith a variety of isotopic analysis, the study identifies the different chemical characteristics ofthe water body of water, and reveals the law of the sea and groundwater interactions, whichprovides a scientific basis for seawater intrusion in Laizhou Bay area trend forecasting,disaster control seawater intrusion. The main results of this paper include the followings:(1) Collecting research results, and combined with the survey data studies, we have gotthat the hydraulic connection between the groundwater in the study area and the sea water isvery close. Three late Pleistocene marine deposits in the northern coastal regions are the mainsource of underground brine of salt. Weihe River paleochannel is a major in shallow aquifersin the region. However, the ancient river in shallow northern coastal communicate with saltybrine body became a sea water people the main channel invasion.(2) The Field Test and indoor water chemistry test results show that the study area fromsouth to north, groundwater chemistry type of HCO3Cl-Caâ†'Cl HCO3-Caâ†'Cl HCO3-Naâ†'Cl SO4-Naâ†'Cl-Na, was a regular change. According to the results of the chemicalcomposition of water, we got division level of standard seawater intrusion by Cl-, TDS,Na++K+, rCl-/rHCO3-, SO42-.(3)The value of combining salinity of groundwater in this area will be divided intofreshwater, brackish water, salt water, and brine. according to the different chemicalcharacteristics of groundwater bodies of water analysis to determine the study area in theprocess of mixing of seawater intrusion occurred first on this basis, the cation dissolutionprecipitation exchange adsorption and varying degrees occurred; according rCl-/r Na+, rMg2+/rCa2+features such as ion ratios, identified in the study area saltwater, brackish water isfresh groundwater mixed with brine formation, some deep underground fresh water down the brine intrusion has also been affected.(4) Through testing and comprehensive analysis of hydrogen isotopes think, obviouslyfresh groundwater in the study area from atmospheric precipitation, while the causes ofQuaternary sea brine and concentrated by the evaporation effect,"Oxygen elegant" quiteserious; Cl-relationship with δ18O show that the study area saltwater, brackish water is mainlyformed by the mixing of fresh water and underground brine.(5) By calculating the saturation of the main mineral found in the study area are in all ofrock salt water not saturated; gypsum and dolomite in the underground fresh water andbrackish water is not saturated with salty water in the brine is saturated; calcite in all watersare substantially saturated. According to the reverse reaction path geochemical simulationresults have occurred in each of the reaction path cation exchange, dolomite, calciteprecipitation mainly based, CO2gas dissipation occurs, and that is manifested as gypsumprecipitation, but also dissolution occurred. |
PDF Full Text Request