Figure F14. Drilling progress in Hole 1256D during Expedition 309. Black line = actual drilling progress versus time, compared to precruise estimates of progress based on penetration rates of 1 (red) and 1.5 (blue) m/h with 54 h rotation time per CC-9 RCB. Bit changes and drill string withdrawals because of equipment damage are indicated. The minimum and maximum predicted target depth to gabbros is shown (see Fig. F11). WSTP = Water Sampling Temperature Probe. ROP = rate of penetration.
Next Section | Table of Contents