SU(3) analysis for B(E2) anomaly

B(E2) anomaly is becoming a hot topic in the field of nuclear structure. Since the B(E2) anomaly was experimentally found, understanding the mechanism of its production has become an important problem. Theoretical studies have found that the SU3-IBM and other extended IBM theories can give explanations, but different mechanisms were found. In this paper, the concept ``SU(3) analysis'' for B(E2) anomaly is proposed, and some new conclusions are obtained. The SU(3) third-order interaction $[L\times Q \times L]^{(0)}$ and level-crossing are both vital for the emergence of the B(E2) anomaly. This technique can help us to better understand the realistic reason of the B(E2) anomaly.