Study On The Design Of Seismic Acquisition Observation System And Influence Factor Analysis For Red Layer

Red layer in the lower member of ES₄-Kongdian Formation is the low-exploration series of strata on the southern slope of Dongying subbasin.Because of its wide distribution of oil and gas wells,it has great exploration potential and it is a more realistic alternative exploration area at the south of Dongying during the China's 12 th five-year plan.In recent years,the red layer exploration of Boxing depression have made some breakthroughs,red layer of Sub-sag belt has become the most realistic alternative strata of the beach and bar era.However,due to the relatively poor layering of red layer,sedimentary characteristics make that the red layer has the seismic response with weak reflection energy and poor continuity;seismic signal shows the characteristics of weak reflection and low signal to noise ratio.While igneous rock at the top of the red layer has a strong speed interface and signal energy,so it formed a strong shielding for the internal signal of red layer.To solve these problems,we start from the targets of red layer to carry out the study on the design of observation system,the selection of seismic excitation conditions and noise suppression,then optimize the observation system and improve the quality of the data acquisition.By means of demonstrating the basic parameters,forward modeling,attribute analysis of observing system,we have found the observation system suitable for the red layer exploration of Gao-94 district and complex sections.Through multiple surface survey methods,we have established a subtle lithology model and velocity model near-surface,conducted the comparative analysis of lithology,ghost,explosives and other triggering factors,and designed the well depth method point by point to ensure the optimum excitation conditions.In a word,we have investigated various types of noise and analyzed noise suppression methods affecting red layer.And we propose low-noise data acquisition methods and composite multi-domain noise suppression technology,which greatly improves the data quality of the red layer.