Establish The Mode Chart Of Facies Deposition Setting By Grain Size Analysis

One of the traditional particle size analysis data of the program relative to targets. For Sedimentary facies in the environment to determine inter-site identification of the particle size data can be used in addition to a number of ways to supplement their determination, through the Mount Royal Linxia Basin Since the grain size profile 21.4Ma.BP characteristics and parameters determined by commonly used methods were judged:Through the analysis of grain size parameters in various sedimentary facies Linxia Basin tend to poor sorting, indicating unstable sedimentary environment; lakes, braided fluvial facies and span a larger skewness, alluvial fan and delta coarse; braid fluvial deposits form the largest negative deviation, and the present multi-peak; peak level and source components than braided fluvial and lacustrine alluvial fan narrower than Delta.;Through the cumulative normal probability curve analysis combined braided fluvial deposits gradually weakened the overall hydrodynamic; but the latter unstable sedimentary environment, significant changes in water flow and sediment sorting poor. Deposition of alluvial fan facies association reflects the characteristics of highly dynamic conditions, the sub-selected combination of the other three sedimentary facies, but still are sorting poor areas; lake delta phase from the typical combination of gravity flow deposits (flood channel deposits material) and non-flood sediment composition, the relatively poor sorting; fan-delta and the lake is very similar to the delta, fan delta large particle size, power stronger than the lake delta.;Through the analysis of grain size parameters of the C-M diagram derived lacustrine sedimentary assemblage fell SR section, in the range of uniform suspension, and the more the smaller the particles, the better sorted sediments, a small amount of coarse sediment, the preliminary view that may be the product of tectonic movement. Braided fluvial investment point composite sample showed relatively poor sorting; a large number of graded suspension of the samples proved the establishment of braided fluvial. Alluvial fan deposits scattered in N-O-P-Q-R section samples paragraph in which NO-OP segment content and more, indicates the two large roll rolling and suspension, handling highly dynamic, large and coarse sediment sorting is poor to verify the deposit has a strong messy deposits in the power and handling.;Through the analysis of grain size parameters of the Friedman plot obtained combination of braided fluvial deposits fell most of the sample point located in the upper left Front line single Goldman, reflecting the river, sediment particle size distribution coarse, poor sorting characteristics; alluvial fan facies investment portfolio samples can be seen from the diagram of sample points alluvial fan located in the upper right Front line single Goldman, sorting skewness greater than 2 the range of about 0.2 to reflect the alluvial fan and braided river sediments, the deposition of delta compared to more coarse particle size distribution, sorting worse characteristics; lakes and fan delta invested in sorting samples skewness greater than 1, the area below 0.2, indicating that separation is better than the alluvial fan, but also smaller skewness characteristics of the overall fan-delta environment sorting and skewness values are relatively large lake delta, indicating that deltaic fan-delta dynamic conditions than the lake slightly, greater separation characteristics of the kinetic energy for discrimination fan delta and lacustrine delta provide an effective way.;Through the skewness and kurtosis of the discrete map the distribution of lake sediments that reflect the combination of icons that kurtosis great uncertainty, hence the lake sediments of the figure used to determine the identification of uncertain composition of formation; and;Braided river facies in the figure the distribution skewness and kurtosis the widest range of wide range of kurtosis on its poor sorting, skewness is also widely distributed and tend to explain the size of small negative bias, indicating that hydrodynamic conditions the existence and contribution of suspended sediment. Alluvial fan is characterized by skewness in the approximate range of the normal and positively skewed, indicating the larger sediment particles, the relative hydrodynamic conditions stronger than any other combination of sedimentary facies, the peak classification of degrees of total range, on behalf of their separation is poor, can represent the characteristics of alluvial fan facies. Lake delta and alluvial fan-fan delta also has a partial degree, but its peak level in the fan delta has a maximum value may occur, generally confirms the delta facies coarse, fan-delta lakes than sorting Delta sorting worse characteristics.The above analysis, summarized the Linxia basin lake sediments in the shallow water facies and lakeshore lake facies of the cumulative probability curves of grain size characteristics and lake delta depositional model of the probability of two cumulative curves and the C-M diagram scatter pattern; Linxia basin, the alluvial fan complete determination mode; lake delta facies cumulative curves can be judged according to their probability and non-flood deposition of ancient floods, but way incomplete. Royal Hill section of the sedimentary environment of five sedimentary facies discrimination mode data can be more granular way to judge, that granular materials can be used as Linxia basin planning phase of five sedimentary facies and feasible application of indicators to other areas phase work plan has certain reference value.