Introduces responses of LWD electromagnetic resistivity tool used in dipping beds and laminated formations;Analyses resistivity curves of the tool penetrating through formation boundaries,and further proposes two methods,one is for accurate orientation of formation layerings,the other is for correct before-bit formation boundary prediction to geosteering the wells to a specific target.

The response characteristics of formation boundary in horizontal well logging are studied.

In logging interpretation,it is suggested that apart from the resistivity data as a priority other logging data should be taken into analysis on the relationship between the well track and the formation and the angle sizes so as to clarify the formation boundary.

Extending behavior of hydraulic fracture on formation interface

Stating from traditional significance, people devoted much attention to applying engineering logging parameters to real time drilling monitoring and formation pressure detection while drilling, but in geologic application aspects,people did not devote attention to applying them to determine fluid property, divide salt bed and determine formation interface.