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The three parameters of P-wave velocity, S-wave velocity, and density have remarkable differences in conventional prestack inversion accuracy, so study of the consistency inversion of the 'three parameters' is very important. In this paper, we present a new inversion algorithm and approach based on the in-depth analysis of the causes in their accuracy differences. With this new method, the inversion accuracy of the three parameters is improved synchronously by reasonable approximations and mutual constraint among the parameters. Theoretical model calculations and actual data applications with this method indicate that the three elastic parameters all have high inversion accuracy and maintain consistency, which also coincides with the theoretical model and actual data. This method has good application prospects. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Metal-defected spinel Mn x Co 3-x O 4 was fabricated by calcining bimetal glycerolates. • A unique Mn-enriched surface results in abundant surface active sites. • Metal defects lead to enhanced electrical conductivity and O 2 adsorption ability. • Mn 1.5 Co 1.5 O 4 exhibits superior performances in ORR and Zn-air battery. Abstract Manganese-cobalt spinel oxides are considered as a class of promising and low-cost electrocatalysts for oxygen reduction reaction (ORR), whose performances largely depend on their electronic structures which can be effectively optimized by defect engineering. Herein, metal defects (manganese vacancies and cobalt vacancies, i.e. V Mn and V Co) were in-situ introduced into spinel Mn x Co 3-x O 4 via a simple solvothermal treatment followed by thermal calcination. Mn-Co glycerolate precursors not only enable controllable synthesis of spinel oxides with variable metallic ratios, but also play a key role in constructing metal defected crystals for their lamellated structure. As a result of the formation rate difference between manganese and cobalt glycerolate, a unique Mn-enriched surface is formed, leading to the increase of highly active sites for ORR. Importantly, the presence of metal defects, confirmed by XRD (X-ray diffraction), element analysis and XAFS (X-ray absorption fine structure spectroscopy), leads to greatly increased electrical conductivity and O 2 adsorption ability, thus bringing about enhanced ORR activity. Especially, metal-defected Mn 1.5 Co 1.5 O 4 , with the optimal Mn/Co ratio, exhibits comparable activity and superior durability to those of the benchmark Pt/C in ORR and displays excellent discharge performance in Zn-air batteries for practical application. This work provides a new way to optimize the electrocatalytic performance of mixed metal spinel oxides via rational defect engineering. [ABSTRACT FROM AUTHOR]