Featured Research

from universities, journals, and other organizations

Finding New Oil In Long-exhausted Oil Wells

Date:
February 3, 2008
Source:
Informscience
Summary:
Oil reappears from time to time in old deposits and long ago exhausted oil wells. Oil sometimes rushes in or sometimes floods back.In the researchers' opinion, to overhaul old oil deposits is currently much more profitable and efficient than expensive geological exploration works at new locations.

Under contemporary conditions, it is more economically sound not to look for new oil fields but to overhaul old ones. Oil reappears from time to time in old deposits and long ago exhausted oil wells.

The earth's crust is similar to a sandwich cake, consisting of hard layers and fractured-porous layers saturated by various fluids, including oil. In some places, the crust is penetrated by an extremely dense network of fissures and ruptures. Ruptures form cavities located almost horizontally and united into a network. All this complicated system is in constant motion due to tectonic forces’ action. The layers are moving, fissures are widening and acting as a rubber bulb: liquid starts coming into formed interstice from surrounding porous layers. In case of significant tectonic tensions, liquid moves at large distances.

This phenomenon attracts attention of multiple researchers. Specialists of the Institute of Oil and Gas Problems under the guidance of Academician Dmitrievsky offer their explanation.

According to the researchers’ opinion, this mechanism of liquid movement in the crust is the most intense and universal among all possible ones. It acts both in ruptures and in thin fractured layers, which stretch at significant distances. Vibrations in the crust drive fluids along all possible directions, including horizontal and even downward directions. Migration occurs along lengthy cavities and fractures systems, located at the depth of 10 to 15 kilometers.

Liquid movement caused by widening of internal cavities is of vibrating character. Oil sometimes rushes in or sometimes floods back. The mode and period of vibration depend on the size of perturbed area. In large porous layers, the vibration period makes about 10 thousand years. In the ruptures, the period is shorter and it varies from a thousand to hundreds and even dozens of years, if rupture zones are located at small depths.

The researchers have investigated the carbohydrates migration process from the petroliferous stratum into the upper layers in several regions. An example can be the Romashinskoye oilfield in Tatarstan. The volume of produced oil there has significantly exceeded the previously asserted reserves. According to the TATANEFT Joint Stock Company’s data, more than 65% of oil in Tatarstan is produced in old oilfields exhausted by 80%. However, supplementary exploration of the known deposits allowed to increment reserves of oil by one and a half times within the last 25 years. In the Romashinskoye oilfield, the researchers also discovered old exhausted drillings with regenerated inflow of oil and oil with water.

The space of oil pools and their reserves increase with increasing rupture network density. It is interesting to note that the depth of sedimentary covering in the zone of the gigantic Romashinskoye oilfield does not exceed 2 kilometers on average, and this mantle does not possess significant oil potential. Most likely, oil cames to these locations from the direction of Pre-Ural downfold.

In the researchers’ opinion, to overhaul old oil deposits is currently much more profitable and efficient than expensive geological exploration works at new locations.


Story Source:

The above story is based on materials provided by Informscience. Note: Materials may be edited for content and length.


Cite This Page:

Informscience. "Finding New Oil In Long-exhausted Oil Wells." ScienceDaily. ScienceDaily, 3 February 2008. <www.sciencedaily.com/releases/2008/01/080131111653.htm>.
Informscience. (2008, February 3). Finding New Oil In Long-exhausted Oil Wells. ScienceDaily. Retrieved August 21, 2014 from www.sciencedaily.com/releases/2008/01/080131111653.htm
Informscience. "Finding New Oil In Long-exhausted Oil Wells." ScienceDaily. www.sciencedaily.com/releases/2008/01/080131111653.htm (accessed August 21, 2014).

Share This




More Earth & Climate News

Thursday, August 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

California Drought Stings Honeybees, Beekeepers

California Drought Stings Honeybees, Beekeepers

AP (Aug. 21, 2014) — California's record drought is hurting honey supplies and raising prices for consumers. The lack of rainfall means fewer crops and wildflowers that provide the nectar bees need to make honey. (Aug. 21) Video provided by AP
Powered by NewsLook.com
Thousands Of Species Found In Lake Under Antarctic Ice

Thousands Of Species Found In Lake Under Antarctic Ice

Newsy (Aug. 20, 2014) — A U.S. team found nearly 4,000 species in a subglacial lake that hasn't seen sunlight in millennia, showing life can thrive even under the ice. Video provided by Newsy
Powered by NewsLook.com
Unsustainable Elephant Poaching Killed 100K In 3 Years

Unsustainable Elephant Poaching Killed 100K In 3 Years

Newsy (Aug. 20, 2014) — Poachers have killed 100,000 elephants between 2010 and 2012, as the booming ivory trade takes its toll on the animals in Africa. Video provided by Newsy
Powered by NewsLook.com
Charter Schools Alter Post-Katrina Landscape

Charter Schools Alter Post-Katrina Landscape

AP (Aug. 20, 2014) — Nine years after Hurricane Katrina, charter schools are the new reality of public education in New Orleans. The state of Louisiana took over most of the city's public schools after the killer storm in 2005. (Aug. 20) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins