Sitakunda Structure one of the westernmost structures of chittagong and chittagong hill tracts. It is situated at the northwestern part of Chittagong district, between 22'34'N and 22'43'N latitude and 91'38'E and 91'41'E longitude. It is delimited in the north by the feni river, in the south by the karnafuli, in the east by the halda river and in the west by the sandwip channel. In a broader sense the Sitakunda Hill Range acts as a water divider between the Halda valley on the east and the Sandwip channel on the west. The structure is about 70 km long and 10-km wide and is situated at about 270-km southeast of dhaka.
The Sitakunda fold is an elongated, asymmetrical, box-type doubly plunging anticline. The axis of the fold is running in NNW-SSE direction, parallel to the general trend of regional strike. Both the flanks of the anticline merge into the alluvial plain of the Feni River in the north and the Karnafuli in the south due to its doubly plunging nature.
The structure has a gently dipping eastern flank and steeper western flank, which is suddenly truncated by the alluvial plain. This truncation is a result of a major faulting that runs parallel to the general strike of the anticline.
The exposed sedimentary rock sequences of the structure, except limestone, provide no difference in overall lithology from that of other structures of Chittagong and Chittagong Hill Tracts. The Sitakunda structure contains a thick sedimentary sequence of sandstone, shale and siltstone. Total thickness of the exposed sediments is about 6,500m. [Sifatul Quader Chowdhury]