However,the interaction among the shape and location of gas pin,gas pressure parameters,and traditional molding parameters often caused injection molding defects such as shine mark, gas finger mark, knit line and so on.

Digit-simulate of Reflect Highlights Model from Submarine;

The structure of highlight echoes due to specular reflection from shells of immerged target;

Two ways to get highlight information of underwater complex target using wideband signal

There are also the analysis on the property and forming mechanism of high-frequency echo highlight.

They have "bright spot" seismic characteristics due to the shallow burial depth,light density,large mudstone segmentation,good physical properties of reservoir,low speed of reservoir and its big difference with wave impedance of surrounding rock.

The results indicate the reservoir characteristics and physical property of T1f1-2 is better,its reflection coefficient is bigger than T1f3,and the characteristics of bright spots and dark spots are obvious in Puguang Gasfield.

The technology of prediction and description of three dimensional gas reservoir,based on the technology of bright spot,including accurate geological research,applying the technology of AVO,multi-parameter extraction and identification of reflection wave,the analysis of bright spot and three dimensional visibility to identify the gas-bearing bed,describe the expanding of the gas reservoir.