About Bioline  All Journals  Testimonials  Membership  News  Donations

Journal of Applied Sciences and Environmental Management
World Bank assisted National Agricultural Research Project (NARP) - University of Port Harcourt
ISSN: 1119-8362
Vol. 10, No. 3, 2006, pp. 31-35
Bioline Code: ja06048
Full paper language: English
Document type: Research Article
Document available free of charge

Journal of Applied Sciences and Environmental Management, Vol. 10, No. 3, 2006, pp. 31-35

 en Lignite Zone as an Indicator to Lost Circulation Belt: A Case Study of Some Locations of Anambra State, Southeastern Nigeria.


Eighteen (18) water boreholes were studied for lost circulation. When locations of the boreholes associated with lost circulation were plotted on the map of AnambraState a lost circulation belt was observed around the River Niger - Onitsha - Oba - Nnewi axis. Lost circulation intervals range between 20-50m and 75-90m depth and were found to be associated with lignite and peaty clay members of the Ogwashi-Asaba Formation and/or the Ameki/Bende Formation. This suggests that natural rather than anthropogenic factors are responsible for the widespread occurrence of lost circulation in the State, although the latter could aggravate the former. Lignite and peaty clay of the Ogwashi-Asaba and Ameki/Bende Formation cause lost circulation because they are woody to earthy in nature and are easily eroded when they occur above the water table. These conditions favour the development of vugs, leading to increase in permeability and porosity, making the formation prone to lost circulation. Pre-drilling geophysical, geological and hydrogeological investigations are recommended, since these would go a long way to identify the presence or absence of lignite and thus help to avert possible lost circulation intervals

© Copyright 2006 - Journal of Applied Sciences & Environmental Management

Home Faq Resources Email Bioline
© Bioline International, 1989 - 2020, Site last up-dated on 29-Jan-2020.
Site created and maintained by the Reference Center on Environmental Information, CRIA, Brazil
System hosted by the Internet Data Center of Rede Nacional de Ensino e Pesquisa, RNP, Brazil