USGS Home
Contact USGS
Search USGS

Figure 127. Well site G4950 (from Dustan et al., 1991). (A) Sketch of site in 70 m of water shows approximate position of various debris objects. A long furrow led from a 60-cm-deep pit at lower right. Dashed line shows approximate limit of zone of visual disturbance. (B) View of disrupted bottom community consisting mainly of red algal nodules and plates. The green alga Caulerpa spp. was common. The submersible measuring chain (at right), composed of 1-cm-long links formed from 1-mm-diameter wire, accidentally dragged laterally (left to right) and disrupted the surface community. Community at top left was undisturbed. (C) View of cement donut or grout mound around well bore. Red grouper hovers over open hole; smaller one swims outside with numerous small silver fish. Both groupers repeatedly disappeared and reemerged from well bore. View is of scoured side of donut grout mound, at right in (A). (D) Closeup of vertical hole of well bore in bedrock. (E) View of pipe at right in (A).

Printable Version (964 KB PDF)

Can't see the printable PDF version? Get the free Adobe Acrobat® Reader.

Coastal & Marine Geology Program > Center for Coastal & Watershed Studies > Professional Paper 1751