A seabed logging R&D study was conducted on the Troll Field in December 2003 – January 2004. Different EM waveforms and frequencies were tested to optimize the hydrocarbon response from this shallow water gas and oil field. The survey consists of 41 receivers, deployed along a line crossing the Oil Province, the Western Gas Province and the Eastern Gas Province of the Troll Field. All receivers recorded two orthogonal components of the horizontal electric field, and 12 receivers measured in addition two orthogonal components of the horizontal magnetic field. The R&D study was carried out as an attempt to qualify seabed logging for shallow waters (less than 500 m) and optimize acquisition parameters for such cases. Up until now the marine controlled source EM method has been qualified for use in deep waters (more than 1000 m water depth) mainly because of the disturbing influence from the air wave in shallower water areas. The Troll Field seabed logging data is of excellent quality and helps in solving problems related to shallow water applications of this method.

1 A05 REMOTE CHARACTERIZATION OF HYDROCARBON FILLED RESERVOIRS AT THE TROLL FIELD BY SEA BED LOGGING Introduction SeaBed Logging (SBL) is a remote sensing technique which gives information about subsurface resistivity variations by the use of electromagnetic energy. The method has been demonstrated both theoretically (Kong et al. 2002) and in practice by several calibration and commercial surveys (Ellingsrud et al. 2002 Røsten et al. 2002 Amundsen et al. 2004 and Wicklund and Fanavoll 2004). This abstract presents preliminary results from a scientific SBL survey across the Troll Field. The overall objective of the study is to obtain an improved

In an effort to understand the history of contamination in Lake Fenwick, this study has examined concentrations of arsenic, copper, and lead in addition to percent organic material present in the sedimentary record. Patterns of chemical concentrations relative to the releases of contaminants from the ASARCO smelter site have been identified. A comparison of concentrations preserved in the sediment core to normal background concentrations and established clean-up levels show that some concentrations in the surface sediment are well above normal. This has implications for public health as well as the overall health of the lake. It is recommended that additional studies be conducted to identify recent/present sources of As and Cu pollution in the lake and that remediation activities be considered as well.