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Nondestructive determination of Au in gold ornaments mainly takes density method and X ray fluorescence spectrometer with energy dispersion (EDXRF), which exists disadvantages. This paper based on the principle of crystallography, deduced the mathematical relationship between the crystallographic parameters, the density and the impurities content in gold jewelry alloys, then introduced the results by density testing and determination of Ag and Cu by EDXRF into the mathematical relationship, and obtained the gold weight percent in gold jewelry alloys. The results show that obtained the gold weight percent and determination of Au by fire assay are almost consistent, which the error is less than 0.12 %, so establishes a synthesis method of determination of Au by EDXRF and density testing, solves the disadvantages which EDXRF only detects on gold jewelry surface and small area, and density testing cannot detect gold jewelry alloy and demands that jewelry shape is simple, and provides an effective synthesis way for determination of Au in gold jewelry alloys.

Based on well logging data, this study has done research of well logging interpretation of Moliqing oilfield in Yitong basin. The Second member of Shuangyang formation is the main area. The main causes of complicated oil-water relationship are as follows: 1) rapid facies change produce diverse lithology distribution, and various lithology have different electrical property standards; 2) complex tectonic characteristics of study area bring about great difficulty in oil and water layer identification, especially a series of small normal faults in deep strata. According to those above, we built logging models in order to get essential parameters firstly. Then, several units of study area were divided. Different electrical property standards were established to solve the problem of recognition of water/oil layers. In total, more than 10,000 sand bodies of 149 wells were interpreted properly, and correct rate is higher than 90%. The conclusion is that oil layers distributed in high position of tectonics. Moliqing oilfield belongs to lithology-tectonic hydrocarbon reservoir.