Abstract: Gas monitoring systems (500) and methods for determining a burning hydrocarbon effluent gas plume property. A laser emission system emits laser beams (564) along a path through the plume (532). A detection system facilitates determining intensity data indicative of intensities of the laser beams (564) backscattered by a surface (522) after passing through the plume (532). The laser emission system emits a first laser beam (564) along the path while tuning its wavelength around a wavelength corresponding to a CO2 spectral absorption line. The laser emission system emits a second laser beam (564) along the path while tuning its wavelength around a wavelength corresponding to a spectral absorption line of a second predetermined gas.

Abstract: Methods for cementing a subterranean well and maintaining zonal isolation involve preparing a cement slurry that contains water, an inorganic cement and an expanding agent. The slurry is placed in the annular region between casing and the formation or between two casing strings. After the cement sets, the expanding agent reacts and causes the set cement to be in a state of compression within the annular region. The casing dimensions may fluctuate in response to a temperature change, a pressure change, a mechanical disturbance resulting from a well intervention, or mud contamination or a combination thereof. The expanding agent may further react and maintain a state of compression within the annular region. The state of compression in the annular region may be monitored by acoustic impedance measurements.

Abstract: A method of cementing a subterranean well to form an expanded set cement acoustically coupled to the casing. Systems for cementing a wellbore are also disclosed.

Abstract: Methods for cementing a subterranean well and maintaining zonal isolation involve preparing a cement slurry that contains water, an inorganic cement and an expanding agent. The slurry is placed in the annular region between casing and the formation or between two casing strings. After the cement sets, the expanding agent reacts and causes the set cement to be in a state of compression within the annular region. The casing dimensions may fluctuate in response to a temperature change, a pressure change, a mechanical disturbance resulting from a well intervention, or mud contamination or a combination thereof. The expanding agent may further react and maintain a state of compression within the annular region. The state of compression in the annular region may be monitored by acoustic impedance measurements.