Missions - Venezuela

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Mission Logs

  1. Discoverer Deep Seas 1
  2. Discoverer Deep Seas 2

  3. Research Themes
  4. Research Locations

Venezuela location map

Overview

Knowledge of the biology of offshore Venezuela is extremely poor, essentially limited to SCUBA diving depths (around 30 metres), with absolutely no biological investigations of the entire bathyal region (depths of 200 to 2,000 metres). Working in collaboration with the Universidad Simón Bolívar in Caracas, SERPENT is using ROVs to explore the diversity and density of the seabed communities in the region. A first trip to the Orca field, north-east of Venezuela in the Orinioco River fan, took place in July/August 2007 to the Sovereign Explorer, enabled through SERPENT partners Statoil, Transocean and Subsea 7.
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Research Themes

Sea floor drill spoil image

Disturbance of sediment environment

The drilling related disturbance to seabed environment can vary from physical stresses such as sediment smothering (as a result of increased sediment accumulation) and changes in the particle size distribution to chemical stresses that are often linked to changes in the physical parameters. For instance, increased sedimentation rate can alter the depth of the oxygenated sediment layer and may be associated with increased concentrations of potentially harmful chemical compounds.

The influence of drilling related disturbance agents on biological communities is poorly understood. This project aims to increase the understanding of these processes through a number of different but complimentary research approaches. The results will help to further develop and improve the management approach of the investigated impacts.

Drill spoil spread diagram

Visual inspection of the seabed

The assessment of physical impacts on the sediment environment around the well head can be made visually by conducting ROV operated video inspections. This involves conducting radiating video transects around the well head and using these data to produce sediment impact maps that help to outline the horizontal extent of the disturbance. The deployment and regular inspection of graduated poles around the well head yields further information on the sediment accumulation along vertical axis providing an additional component to sediment impact maps.

Seastar image

Biological community analysis

Biological community analysis is conducted at two different scales. First, the video transect data together with high-quality digital stills photography is used to assess the community composition and biodiversity of the larger, surface-dwelling organisms (megafauna). This involves identifying the animals, classifying their functional roles and assessing their abundance levels. The video and photography footage also provides important insights into the behaviour of many of these species.

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Research Locations

Venezuela

Orca Prospect

The Orca well is located west-north-west of Maturin, Venezuela. Water depth at this location is 543m and the bottom water temperature was recorded as 3°C (26th July 2007). The exploration activities at the Orca location allowed for two surveys to take place (pre- and post-tophole drilling).