Sedimentary core brGDGTs in the East China Sea are mainly produced in situ as evidenced by their similar distributions with brGDGTs derived from intact polar lipids

•Distribution of sedimentary core and IPL-derived brGDGTs are similar in ECS.•Distribution of sedimentary brGDGTs in ECS differs from global soils.•MBT′5ME values for core and IPL-derived brGDGTs decrease with increasing latitude.•#Ringstetra values for core and IPL-derived brGDGTs increase offshore.•Age differences lead to larger IPL-core offset in MBT′5ME and #Ringstetra offshore.