El presente libro representa una contribución extraordinaria al conocimiento de la geomorfología del fondo marino profundo en la región sur del Caribe colombiano. El levantamiento batimétrico con técnicas de sonda multihaz revela, por primera vez, la gran complejidad morfológica de esta región, mapeando geoformas que hasta ahora eran desconocidas. El importante volumen de datos recopilados y los métodos modernos empleados para la tipificación de las diferentes geoformas, contribuyen con unos resultados de calidad sin precedentes. Con la lectura de esta obra, los estudiantes universitarios y los profesionales aprenderán y disfrutarán de datos y explicaciones siempre acompañadas de imágenes de calidad. Todo ello hará que el lector, incluso el menos especialista, se sumerja en las complejas pero bellas profundidades del Caribe colombiano.

Submarine landslides can be triggered by several processes and involve a variety of mechanisms. These phenomena are important sediment transport processes, but they also constitute a significant geohazard. Mapping of the southwestern Caribbean Sea using 3D seismic data has allowed identification of several submarine landslides in the Colombian Margin in the area dominated by the Southern Sinú Fold Belt (SSFB). A poststack depth-migrated seismic cube survey with a 12.5 by 12.5 m bin spacing was used to identify landslides in an area covering 5746 km2. Landslides were interpreted using a seafloor morphologic parameter identification process and the internal deformation of the slope-forming material, as seen from seismic data. A total of 93 landslides were identified and classified based on their movement styles as follows: 52 rotational, 29 translational, and 12 complex landslides. In addition, 12 distinct deformational zones and a zone of mass transport complex (MTC) were identified. Five different ground condition terrains were interpreted based on landslide type and distribution as well as in geologic structures and seismic reflection analysis. Two main processes seem to influence landslides in the study area. First is the folding and faulting involved in the SSFB evolution. This process results in oversteepened slopes that start as deformational zones and then fail as translational or rotational slides. Those individual landslides progressively become complex landslide zones that follow geologic structural orientation. Second is the continental shelf break erosion by debris flows, which fills in intraslope subbasins and continental rise with several MTCs. According to the results, risk of damage by landslides increases in distances shorter than 4 km along structural ridge foothills in the study zone.

Submarine landslides are a mixture of rock, sediment, and fluids moving downslope due to a slope's initial event of mechanical failure. Submarine landslides play a critical role in shaping the morphology of the seafloor and the transport of sediments from the continental shelf to the continental rise in the southern margin of the Colombian Caribbean. Two fundamental considerations can be highlighted: first, mass transport complexes produced by submarine landslides encompass significant portions of the stratigraphic record; second, these mass movements could affect underwater infrastructure. The mapping of the Southern Caribbean seafloor using 3D seismic surveys and multibeam bathymetry data in an area encompassing 59,471 km2 allowed the identification of 220 submarine landslides with areas ranging between 0.1 and 209 km2. Distinctive characteristics were found for submarine landslides associated with canyon walls, channel-levee systems, tectonically controlled ridges, and the continental shelf break. The analysis of the relationship between submarine landslides and seafloor morphological features made it possible to estimate a mass movement susceptibility map that suggests the following considerations: first, structural ridges and adjacent intraslope subbasins related to the South Caribbean Deformed Belt are more likely to be submarine landslide hazards; second, the continental shelf break and channelized systems produce a moderate submarine landslide hazard potential; and third, deep marine systems with a slope less than 5° show the lowest submarine landslide hazard potential. This work contributes to the understanding of submarine landslides in the study area through the presentation of conceptual diagrams that provide additional visual elements facilitating the level of abstraction necessary for visualizing bathymetric data. Likewise, the mass movement susceptibility map presented herein gives insights for future studies that seek to evaluate geohazards in the southern Colombian Caribbean margin.

ResumenDurante una perforación es de gran importancia tener una ventana de estabilidad lo más precisa posible para evitar problemas como colapso del pozo, influjos, pérdidas de circulación o de filtrado, entre otros. Aunque la geomecánica permite determinar una densidad óptima, en la realidad pueden existir formaciones permeables por las cuales pueden ocurrir pérdidas de filtrado considerables lo cual aumenta los costos. En literatura existe un modelo matemático que proviene de la ley de continuidad, una ecuación de estado y una ecuación de flujo (Darcy) el cual es utilizado en análisis de pruebas de presión, analizando la presión necesaria para tener flujo de la formación hacia el pozo. El objetivo de esta investigación es demostrar que este modelo se puede implementar para estimar la presión permitida del lodo durante la perforación y controlar el filtrado del este fluido hacia la formación para de esta forma, adicionar una nueva curva a la ventana de estabilidad. Para lograr tal objetivo se utilizaron modelos y correlaciones y se dio un estimado de las propiedades de la formación en función de la profundidad y con un caudal máximo permitido de pérdidas de filtrado, se determinó la presión adicional a la presión de formación con la cual se puede perforar sin presentar grandes pérdidas de filtrado disminuyendo los costos. Finalmente, se hizo un análisis de sensibilidad concluyendo que la permeabilidad y la viscosidad, son las variables más importantes del modelo. AbstractDuring a drilling, it is very important to have a stability window as accurate as possible to avoid problems such as collapse of the well, loss of circulation or filtration, among others. Although geomechanics makes it possible to determine an optimum density, in reality there may be permeable formations whereby considerable filtration losses can occur which increases costs and NPT. In literature there is a mathematical model that comes from the law of continuity, a state equation and a flow equation (Darcy) which is used in pressure test analysis, analyzing the pressure needed to have flow from the formation to the well . The objective of this research is to demonstrate that this model can be implemented to estimate the allowed pressure of the sludge during the drilling and to control the filtration of this fluid towards the formation in order to add a new curve to the stability window. To achieve this objective, models and correlations were used and an estimate of the properties of the formation as a function of depth and with a maximum allowed filtration loss rate was determined, the additional pressure was determined with which It can perforate without presenting great loss of filtration reducing costs. Finally, a sensitivity analysis was made concluding that permeability and viscosity are the most important variables of the model.