Abstract: The invention is a method for monitoring subsidence of the sea-bed (14) of a survey area (8) caused by compaction of an underground hydrocarbon reservoir (1), and comprises the following steps: Conducting at least two series (S1, . . . ,Si, . . . ,Sm) of time-indexed depth measurements (13a, . . . ,13n), with separation in time &Dgr; between the measurement series characteristic of a significantly detectable long-term change of seafloor elevation due to compaction to take place in the reservoir. Measurements are time-indexed and corrected for tidal depth variations. Depth measurements (13) are conducted on survey stations (2) arranged on benchmarks (6) which have settled in the locally consolidated seabed (14). To handle short-term depth variations several stationary time-indexed short-time local reference depth measurement series (19r) are conducted at short-term local reference stations (18r) at benchmarks (6) during each separate measurement series (Si).

Abstract: Infrasound signals in the band 0.02 to 4 Hz are sensed in the presence of ambient noise generated chiefly by wind as integrated pressure variations, which induce detectable changes in the optical path length, along optic fibers, typically extending 100 m. to 1000 m. and more, arrayed at arbitrary geometries. Two fibers connected as a Michelson, Mach-Zehnder or equivalent interferometer where (i) one fiber is coupled to atmosphere while (ii) the other is not for being hermetically sealed in a tube, permit common mode rejection of noise from (i) temperature changes and (ii) strain, including ground vibration. Because the optic fiber infrasound sensors are longer than the distance over which wind-induced pressure changes are coherent, the effects of wind noise on the sensing of infrasound is reduced, and signal-to-noise ratio is increased over a wide bandwidth.

Abstract: A method for filling a ladle cup of a ladle assembly with molten aluminum to reduce formation of aluminum oxides. The ladle cup is rotated into alignment with an axis of a ladle arm, which carries the ladle cup, such that a plane defined by the ladle cup rim is generally parallel to the ladle arm axis and the opening of the ladle cup faces parallel to a surface of the molten aluminum. The ladle cup is inserted into the bath of molten aluminum while maintained in alignment with the ladle arm axis. When the ladle cup reaches its final position within the bath of molten aluminum, the ladle cup is rotated to a desired angular orientation, which corresponds to a desired shot weight, and then is raised out of the molten aluminum while being retained in the desired angular orientation.

Abstract: A method for filling a ladle cup of a ladle assembly with molten aluminum to reduce formation of aluminum oxides. The ladle cup is rotated into alignment with an axis of a ladle arm, which carries the ladle cup, such that a plane defined by the ladle cup rim is generally parallel to the ladle arm axis and the opening of the ladle cup faces parallel to a surface of the molten aluminum. The ladle cup is inserted into the bath of molten aluminum while maintained in alignment with the ladle arm axis. When the ladle cup reaches its final position within the bath of molten aluminum, the ladle cup is rotated to a desired angular orientation, which corresponds to a desired shot weight, and then is raised out of the molten aluminum while being retained in the desired angular orientation.

Abstract: The invention is a method for monitoring subsidence of the sea-bed (14) of a survey area (8) caused by compaction of an underground hydrocarbon reservoir (1), and comprises the following steps: Conducting at least two series (S1, . . . ,Si, . . . ,Sm) of time-indexed depth measurements (13a,.., 13n), with separation in time &Dgr; between the measurement series characteristic of a significantly detectable long-term change of seafloor elevation due to compaction to take place in the reservoir. Measurements are time-indexed and corrected for tidal depth variations. Depth measurements (13) are conducted on survey stations (2) arranged on benchmarks (6) which have settled in the locally consolidated seabed (14). To handle short-term depth variations several stationary time-indexed short-time local reference depth measurement series (19r) are conducted at short-term local reference stations (18r) at benchmarks (6) during each separate measurement series (Si).