Site 1252 (proposed Site HR5a) was drilled in ~1040 m of water ~4.5 km northeast of the southern summit of Hydrate Ridge. The site is located on the western flank of a secondary anticline that is located east of the crest of Hydrate Ridge. The sediments in the core of the anticline appear to be continuous with the accretionary complex sediments sampled near the base of Site 1244, ~1.5 km to the west. Although there is an anomalously bright bottom-simulating reflector (BSR) at a depth of ~170 meters below seafloor (mbsf) within the core of the anticline, the BSR disappears abruptly and does not extend beneath Site 1252 (see Fig. F8 in the "Leg 204 Summary" chapter). Sediments onlapping the anticline from the west can be correlated with sediments sampled at Site 1251.
The principal objectives at Site 1252 were the following:
This is the only site at which we did not acquire logging-while-drilling (LWD) data. One hole was drilled at Site 1252 (Fig. F1), comprising 28 cores to 260 mbsf.
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