Lithological density logger detector

The utility model relates to a lithological density logger detector which comprises a detector outer shell, a protective cap, a gamma emission source, a source bin fixing shell, a short spacing receiving crystal and a long spacing receiving crystal. Long spacing from the gamma emission source to the center of the long spacing receiving crystal is 375.92mm millimeters, and short spacing from the gamma emission source to the center of the short spacing receiving crystal is 153.67millimeters. the counting rate is commonly improved by more than one time through correction selection of the spacing, the counting rate is improved by more than two times in a stratum larger than 2.7 grams per cubic centimeter, statistical fluctuation is greatly reduced, measurement accuracy is superior to measurement accuracy in the prior art by 0.025 gram per cubic centimeter, and repeatability is greatly improved.