Method of Wavelet Multiscale Analysis and Its Application in Division of Sedimentation Cycle of Lake Facies Mudstone

Lake facies mudstone includes affluent information of geohistory evolution process, and displays the character of multi-scale sedimentary cycles. These properties are more or less recorded in geophysical well logs. This paper appropriately applies the wavelet method for analysing the multiscale character of gamma-ray (GR) logs. We successfully extract the information of depositional units and sedimentary cycles of mudstone from two-dimensional time-frequency scalogram. Experimental results are well corresponding with other geological and geochemical properties. All the efforts in this paper are considered as an effective tool to recognize vertical heterogeneous distribution of organic content in source rock, and prospect profitable subtle reservoirs.