9. A system for automated interpretation of well log data indicative of physical attributes of a portion of a subterranean formation comprising: a data storage device, configured and arranged to store the well log data; a processor, configured and arranged to execute machine executable instructions to partition the well log data into segments, each segment representing a respective contiguous portion of the extent of the logged well; define a membership function for each segment, the membership function defining a degree to which each segment belongs to a defined set; determine, based on attribute values derived from previously interpreted depositional units, and the membership functions, a depositional type for each segment; and converting, via computer, the well log data to shale volume data, wherein the shale volume data are represented as a series of numerical values V sh =s 1 , s 2 , . . . , s i , where s i is an average of the shale volume data within the ith segment.
9. A system for automated interpretation of well log data indicative of physical attributes of a portion of a subterranean formation comprising: a data storage device, configured and arranged to store the well log data; a processor, configured and arranged to execute machine executable instructions to partition the well log data into segments, each segment representing a respective contiguous portion of the extent of the logged well; define a membership function for each segment, the membership function defining a degree to which each segment belongs to a defined set; determine, based on attribute values derived from previously interpreted depositional units, and the membership functions, a depositional type for each segment; and converting, via computer, the well log data to shale volume data, wherein the shale volume data are represented as a series of numerical values V sh =s 1 , s 2 , . . . , s i , where s i is an average of the shale volume data within the ith segment. 10. The system as in claim 9 , further including an input device, configured and arranged for a user to input adjustments to boundaries of the segments.