A technique is described for collecting reef interstitial water using manually-driven well points. This method does not require the use of hydraulic drills, and eliminates the problems associated with the casing of boreholes. The technique allows collection of samples from discrete depths within reef frameworks, and produces samples unaffected by atmospheric or surface seawater contamination. D...

We have created a tunable mechanical nanoscale resonator with potential applications in precise mass, force, position, and frequency measurement. The device consists of a specially prepared multiwalled carbon nanotube (MWNT) suspended between a metal electrode and a mobile, piezo-controlled contact. By exploiting the unique telescoping ability of MWNTs, we controllably slide an inner nanotube c...

The acoustic logging method is the most commonly used to qualify a cement job. It can be run several hours or days after placement and evaluates quality of bond (acoustic coupling) between casing, formation. measures attenuation sound signal as it propagates through formation returns sensor. This technique will help spot free pipe, partially bonded fully pipe. aim this paper analyses logs data ...

This paper presents a numerical model of an integrated 3D casing-cement-formation system, to evaluate the mechanical tensile and shear failure cement at casing-cement interface as pressure temperature conditions formation borehole vary during production. The which includes pressure, unlike others proposed, was developed by stages under finite element discretization compared analytical models. R...

Corrosion monitoring and early detection of pits and wall thinning for casing pipes are considerably important to gas and petroleum industries since the frequently occurring corrosion at the internal or external parts of those steel casing pipes used in underground gas storage or oil fields causes production and environmental protection problems. In this paper, a new version of the direct curre...

It has long been known that temperature during circulation and after cement placement is one of the most important parameters for slurry design and the success in cement production. Conventional cements and low density cement slurries usually take a long time to set and cannot provide significant compressive strength. Therefore, it is important to design appropriate low density cement slurries ...