Detrital Mineralogy And Its Environmental Indicative Significance Of The Sediments Of Coastal Zone In Liaodong Bay

The research of Sedimentary characteristics of marine sediment and its sources is animportant content of marine geology, which is the main issue of the study modern deposition.Through sediment grain size, clastic minerals and clay minerals, element geochemistry,isotope tracer and biological combination for comprehensive discriminant analysis thesedimentary environment and provenance can be verified. In order to indicate the sedimentand sedimentary environment, through the heavy and light mineral assemblages analysis ofclastic sediments in the surface samples and core specimens, characteristics of single grainsize (fine sand0.063-0.125mm) were discussed.Carrying mineralogy, grain size analysis and sedimentary dynamics method on thesurface samples38in the coastal zone,43of rivers,14core (271samples identified) sedimentsamples, in the study area. Mineral composition, diffusion and movement trend wereinvetigated, and system cluster analysis methods of mineral index be used to distinguishmineral provinces and sedimentary environment etc.Applying Comparative analysis of very fine sand and heavy mineral of the sediments inthe study area shows significantly negative correlation between the two. Content of very finesand can reflect water environmental conditions. The sediments dominated by particles in theestuary area of Liaohe River, Dalinghe River which water energy is relatively weak, but grainsize of sediments in the East coast of Liaodong Bay is coarse, indicating stronghydrodynamic.Forty-one kinds of heavy minerals have been identified in the study area by mineralanalysis, which are mainly amphibole, epidote, garnet, magnetite, ilmenite and sphene.Approximately11kinds of light minerals mostly are quartz， feldspar (mainly plagioclase).Application of Q type cluster analysis of the surface sediments of the studied area can bedivided into3mineral provinces; provinceⅠ，garnet was treated as diagnostic mineral, andilmenites take a primary position of the metallic minerals, all of which minerals are mainlyderived from Fuzhouhe River and substance eroded from the coast, which may be the relatedto Liaodong Shoal. In provinceⅡ (the north of Fuzhou Bay-Yingkou), diagnostic mineralsmainly include sphene and zircon, whose material characteristics are mainly influencedremarkably by the sediment of Daliaohe River and nearby short rivers. In addition, the highest content of metallic minerals is magnetite. In provinceⅢ(Yingkou-Qinhuangdao), the limoniteis the main component in the metallic minerals and diagnostic mineral is garnet and apatite,the detritus of Liaohe River and Liuguhe River prominently contribute to its mineralassemblages.Since the content of very fine sand in the14cores are fluctuated from top to bottom，thechange of hydrodynamic can be reflected. Heavy mineral analysis showed that，content ofunstable mineral of the study area is of a high level or degree，the varied content ofAuthigenic pyrite in the core， reflect the metabolic oxidation reduction of the sedimentaryenvironment and sorting. Studies have shown The two sides shore water power is relativelystrong, while hydrodynamic force top of the bay is weak, which is consistent with theconclusions of the grain size analysis.