Methods of evaluating rock properties while drilling using downhole acoustic sensors and a downhole broadband transmitting system

摘要

Methods of identifying rock properties in real-time during drilling, are provided. An example of such a method includes connecting a downhole sensor subassembly between a drill bit and a drill string, operably coupling acoustic sensors to a downhole data interface, and operably coupling a surface computer to the downhole data interface. The method can also include receiving raw acoustic sensor data generated real-time as a result of rotational contact of the drill bit with rock during drilling, transforming the raw data into the frequency domain, filtering the transformed data, and deriving a plurality of acoustic characteristics from the filtered data. This can be performed by a petrophysical properties analyzing program stored in memory of the computer. The method can also include deriving petrophysical properties from the filtered data utilizing a petrophysical properties evaluation algorithm employable to predict one or more petrophysical properties of rock undergoing drilling.