Heritage Community Foundation Presents
Alberta Online Encyclopedia
SitemapSearchHelpContactPartnersEdukitsHome
Resource Inventory
History of Development
Innovation and New Technology Visit Alberta Source! Heritage Community Foundation
Heritage Trails presented courtesy of CKUA Radio Network Canada's Digital Collections

Home > Alberta's Resource Inventory > Hydrocarbons > Crude Oil > Resource Development > Drilling > Well Control > Logging and Testing

Resource Inventory

Logging and Testing

Gas Drilling RigThroughout drilling, various logs are plotted to record the well's progress. The record includes data about the type and thickness of rock layers, based on the well site geologist's examination of cuttings brought to the surface during drilling. The speed of penetration is also recorded because the first sign of possible success is usually an increase in the rate of penetration followed by the appearance of oil or gas traces in cuttings. If more information is needed about the rocks, a special cylindrical bit may be used to cut a core sample for analysis by geologists, reservoir engineers, geochemists and palynologists.

Further information is obtained by lowering a package of instruments, called wireline logging tools, into the wellbore. The instruments record and transmit information about the rock layers' thickness, porosity and permeability and the composition of fluids, such as oil, gas or water, contained in them.

A logging instrument can also be mounted on the string above the bit to send information continuously during drilling. It sends signals to the surface by means of pulses, like sonar signals, in the mud. Another instrument, the measurement-while-drilling (MWD) tool, can similarly measure the direction and precise location of the bit while drilling horizontal wells.

A common way to determine potential oil or gas production is the drillstem test, which uses a special tool in place of the bit on the end of the string. The tool has valves and rubber sleeves, called packers, that can be controlled from the surface. First, the packers are expanded to isolate the section of the hole to be tested. Next, valves on the tool are opened, allowing liquids or gas from the formation to flow into the empty drill pipe. This gives a good indication of the type and volume of the fluids in the formation, their pressure and rate of flow.

Petroleum Communication Foundation. Our Petroleum Challenge: Exploring Canada's Oil and Gas Industry, Sixth Edition. Calgary: Petroleum Communication Foundation, 1999. With permission from the Centre for Energy.

previousNext

   


Soil and AgricultureHydrocarbonsForests


Albertasource.ca | Contact Us | Partnerships
            For more on natural resources in Alberta, visit Peel’s Prairie Provinces.
Copyright © Heritage Community Foundation All Rights Reserved