 Complete the following phrase:  A trench investigation conducted across the Dauki Fault at Gabrakhari Village, on the western part of the Dauki fault, inferred the timing of seismic events dating back to A.D. 15001630. The seismic event during A.D. 15001630 may correspond with the 1548 Bengal earthquake, the first recorded large earthquake of Bangladesh. Sand dikes, which reach near the ground surface due to paleo-liquefactions, were confirmed at the trench. These sand dikes formed during the 