Karst hydrogeology of the Chalk and implications for groundwater protection

نویسندگان

چکیده

Abstract The Chalk is an unusual karst aquifer with limited cave development, but extensive networks of smaller solutional conduits and fissures enabling rapid groundwater flow. Small-scale features (stream sinks, dolines, dissolution pipes, springs) are common, hundreds stream sinks recorded. Tracer velocities from 27 connections between springs have median mean 4700 4600 m d −1 . Tests to abstraction boreholes also demonstrate very thousands metres per day. Natural gradient tests observation There strong geological control on focused stratigraphical inception horizons. Surface concentrated near the Paleogene boundary, or where thin superficial cover occurs, flow common in other areas. has higher storage contaminant attenuation than classical karst, recharge, influenced by karst. Point recharge through losing rivers, vertical fissures, soakaways enables unsaturated zone Saturated create vulnerability subsurface activities, enable long distance transport point source diffuse pollutants, which may be derived outside modelled catchment areas protection zones.

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Artificial recharge of groundwater: hydrogeology and engineering

Artificial recharge of groundwater is achieved by putting surface water in basins. furrows, ditches, or other facilities where it infiltrates into the soil and moves downward to recharge aquifers. Artificial recharge is increasingly used for shortor long-term underground storage. where it has several advantages over surface storage, and in water reuse. Artificial recharge requires permeable sur...

متن کامل

Medical Hydrogeology of Asian Deltas: Status of Groundwater Toxicants and Nutrients, and Implications for Human Health

Drinking water, a fluid primarily for human hydration, is also a source of mineral nutrients. Groundwater, a drinking water source for more than 70% of inhabitants living in Asian deltas, has received much attention because of its naturally occurring arsenic, but the linkage of arsenic toxicity with other water constituents has not been studied. In addition, although nutrients are generally pro...

متن کامل

Karst groundwater management by defining protection zones based on regional geological structures and groundwater flow fields

Karst regions, occupy approximately 25% of the land surface of the earth. Karst aquifers are often major sources of water supply in these areas. However, karst aquifers are generally considered to be particularly vulnerable to pollution and anthropogenic impacts. Large withdrawals of water in karst areas for municipal, agricultural, and industrial use may competitively affect water supply in su...

متن کامل

Pesticide fate and behaviour in the UK Chalk aquifer, and implications for groundwater quality

Field and laboratory studies have been used to assess the main factors that determine the fate and behaviour of agricultural herbicides in the Chalk aquifer of southern England. Field studies using isoproturon, chlortoluron and atrazine showed that leaching of pesticides from normal agricultural usage produces concentrations in Chalk groundwater of 0.01–1 μg l–1 for most compounds, which are co...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Geological Society, London, Special Publications

سال: 2021

ISSN: ['2041-4927', '0305-8719']

DOI: https://doi.org/10.1144/sp517-2020-267