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accurate record of surveyed prone to soil scour. The infrastructure is essen- response of the structures tial before launching any to ground motions caused operations. by earthquakes, however, is

In contrast with the US a critical factor for foun- shelf areas, where opera- dation design. Structures tors need to be concerned also need to be designed to with highly mobile soils and accommodate lateral loads

Geology & Geophysics punch-through hazards from from tropical storms and shallow sands, the Bay of hurricanes. Storms crossing

Campeche soils are calcare- the Bay of Campeche are ous. Foundation designs that less frequent than those that are successful in the north- affect oil feld structures ern Gulf of Mexico are not in the northern Gulf of adequate for calcareous sedi- Mexico, but they still occur ments, in which the bearing and have to be factored into capacity of piled foundations designs.

Shell’s Perdido platform in the Gulf of Mexico in 2010. Photo from Shell.

can be signifcantly weaker. Pervasive shallow gas

Indeed, not only are the soils generally design parameters that are calculated has to be carefully mapped and moni- weaker, but in certain layers they are from laboratory analysis of geotechnical tored when planning the installation also prone to cementation along certain samples. Anomalous zones of weakness, of structures. Out-of-date surveys will discrete formations where there is more such as buried reefs, are also common not suffce since enhanced oil recovery sand content. and must be identifed and avoided when (EOR) effects need to be anticipated.

Knowing the distribution of these designing foundations for structures.

New deepwater developments subsurface layers and the juxtaposition Other conditions affecting foundation in the Mexican Ridges of geotechnical properties is critical design are slope stability, currents and for site specifc foundation design. The scour, and seismic response, although Mexico’s frst deepwater development main derivations, pile drivability and slope stability is generally not a concern will be the Lakach gas feld, in 1000m end-bearing capacity under vertical and in most of the fat Bay of Campeche; water depth, about 100km off the Port lateral loads, are critical installation and nor is the area, with a few exceptions, of Veracruz. Here the geologic setting

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