Month: July 2009

Gas contracts are divided into long term contracts (over one year but often up to 10-20 years), mid-term contracts (approximately up to five years but can be as short as between one month to one year) and short term contracts or master sales agreements (usually up to 1 month or on a cargo-by-cargo basis for LNG), spot contracts (day of purchase). Traditionally, natural gas contracts were on a long term basis fixing the price, volume and conditions over the term of the contract, thus reducing supply and price risks, but they provided little flexibility to adapt to changing market conditions.

OPERATION LORAN is a net work of land based radio transmitters and was developed to provide an accurate system for long range navigation. LORAN Stations Operations are organized into sub-groups of four to six stations called ” CHAIN “.One station in the Chain is designated the ” MASTER ” and others are called ” SECONDARY ” or ” SLAVE ” Stations

Measurements-while-drilling (MWD) and logging-while-drilling (LWD) logs are also taken downhole. They are either transmitted to surface by mud pulses, or else recorded downhole and retrieved later when the instrument is brought to surface. The measurement of formation properties during the excavation of the hole, or shortly thereafter, through the use of tools integrated into the bottomhole assembly. LWD, while sometimes risky and expensive, has the advantage of measuring properties of a formation before drilling fluids invade deeply. Further, many wellbores prove to be difficult or even impossible to measure with conventional wireline tools, especially highly deviated wells. In these situations, the LWD measurement ensures that some measurement of the subsurface is captured in the event that wireline operations are not possible.

A tool attached to a cable which is lowered into a well to survey the borehole before it is cased