Groundwater residence time in basement aquifers of the Ochi-Narkwa Basin in the Central Region of Ghana

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21110%2F17%3A00321333" target="_blank" >RIV/68407700:21110/17:00321333 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/60460709:41330/17:74732

Výsledek na webu

<a href="http://dx.doi.org/10.1016/j.jafrearsci.2017.07.028" target="_blank" >http://dx.doi.org/10.1016/j.jafrearsci.2017.07.028</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jafrearsci.2017.07.028" target="_blank" >10.1016/j.jafrearsci.2017.07.028</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Groundwater residence time in basement aquifers of the Ochi-Narkwa Basin in the Central Region of Ghana

Popis výsledku v původním jazyce

Groundwaters from basement aquifers in the Ochi-Narkwa basin of the Central Region together with rain and surface waters have been analysed for stable isotopes (d18O, d2H and d13C) and radioisotopes (3H and 14C) to determine sources of recharge, groundwater residence time and flow path. The mechanism of recharge to the groundwaters is by direct infiltration of past local rainfall of mean isotopic composition d18O1/43.8permilleV-SMOW and d2H1/418permilleV-SMOW. Tritium in the groundwaters ranged from 0.05 ± 0.07 to 4.75 ± 0.16 TU. Tritium data revealed that 85% of the groundwater samples were of modern recharge or young waters. The 14C content of the groundwaters ranged between 9.50 pMC in borehole CR2-50 at Ekumfi Asokwa to 113.56 pMC in borehole CR3-26 at Onyaadze. Evaluation of 3H and 14C data distinguished three groups of water namely (1) waters characterised by high 3H and high 14C depicting modern recharge, (2) waters showing a mixture of young and old water due to fractures and (3) waters showing low 3H and low 14C contents referred to as very old waters and include borehole CR2-50 at Ekumfi Asokwa. The estimated age or residence time of this older water is 19,459 years BP based on uncorrected age. The major flow direction is northwest-southeast. The dominant months contributing to recharge in the study area were February, March, April, May, June, August, September and October. Groundwater residence times in the basement aquifers of the Ochi-Narkwa basin showed that groundwater abstraction is sustainable and requires that the recharge areas are protected from contamination.

Název v anglickém jazyce

Groundwater residence time in basement aquifers of the Ochi-Narkwa Basin in the Central Region of Ghana

Popis výsledku anglicky

Groundwaters from basement aquifers in the Ochi-Narkwa basin of the Central Region together with rain and surface waters have been analysed for stable isotopes (d18O, d2H and d13C) and radioisotopes (3H and 14C) to determine sources of recharge, groundwater residence time and flow path. The mechanism of recharge to the groundwaters is by direct infiltration of past local rainfall of mean isotopic composition d18O1/43.8permilleV-SMOW and d2H1/418permilleV-SMOW. Tritium in the groundwaters ranged from 0.05 ± 0.07 to 4.75 ± 0.16 TU. Tritium data revealed that 85% of the groundwater samples were of modern recharge or young waters. The 14C content of the groundwaters ranged between 9.50 pMC in borehole CR2-50 at Ekumfi Asokwa to 113.56 pMC in borehole CR3-26 at Onyaadze. Evaluation of 3H and 14C data distinguished three groups of water namely (1) waters characterised by high 3H and high 14C depicting modern recharge, (2) waters showing a mixture of young and old water due to fractures and (3) waters showing low 3H and low 14C contents referred to as very old waters and include borehole CR2-50 at Ekumfi Asokwa. The estimated age or residence time of this older water is 19,459 years BP based on uncorrected age. The major flow direction is northwest-southeast. The dominant months contributing to recharge in the study area were February, March, April, May, June, August, September and October. Groundwater residence times in the basement aquifers of the Ochi-Narkwa basin showed that groundwater abstraction is sustainable and requires that the recharge areas are protected from contamination.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10501 - Hydrology

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of African Earth Sciences

ISSN

1464-343X

e-ISSN

1879-1956

Svazek periodika

134

Číslo periodika v rámci svazku

N/A

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

10

Strana od-do

590-599

Kód UT WoS článku

000412609000050

EID výsledku v databázi Scopus

2-s2.0-85026725879