Hydrogeology Journal

, Volume 17, Issue 8, pp 1849–1858 | Cite as

Analysis of flow processes in fractured chalk under pumped and ambient conditions (UK)

  • A. P. Butler
  • S. A. Mathias
  • A. J. Gallagher
  • D. W. Peach
  • A. T. Williams
Paper

Abstract

An integrated set of different measurements has been used to study the behavior of groundwater in an observation well in a fractured rock formation, the UK Chalk, under pumped and ambient conditions. Under pumped conditions, the response of the open borehole was relatively straightforward with flow mainly concentrated along four discrete flow horizons. Furthermore, excellent correspondence was observed between the three methods of borehole flow velocity measurement: impeller flowmeter, heat-pulse flowmeter and dilution testing. Under ambient conditions, the system appeared more complicated. Specifically, in the upper half of the borehole, the impeller flowmeter exhibited substantial downward flow and the heat-pulse flowmeter exhibited almost negligible upward flow, whilst dilution testing indicated significant dilution. It was concluded that this was due to cross-flow occurring over the upper 29 m. Analysis of drawdown data, recovery data and a Drost analysis of the ambient cross-flow data yielded aquifer transmissivity estimates of 2,049, 2,928 and > 4,388 m2/day respectively. The discrepancy between the drawdown and recovery estimates was attributed to non-linear head-losses associated with turbulence and inertial effects. The difference between the pumping test and Drost results was explained by the flow during the pumping test bypassing this aforementioned 29 m region of rock.

Keywords

Dilution test Fractured rocks Hydraulic testing Pumping test UK 

Analyse des processus d’écoulement dans un aquifère fissuré de la craie en conditions de pompage et en conditions naturelles (Royaume Uni)

Résumé

Un ensemble de différentes mesures a été utilise afin d’étudier le comportement hydraulique de l’eau souterraine dans un piezometer d’une formation fissurée de la Craie du Royaume Uni, en conditions de sollicitation par pompage et en conditions naturelles. La réponse d’un des ouvrages en conditions de pompage était relativement directe avec un écoulement principalement concentré le long de quatre horizons spécifiques. De plus, les résultats obtenus à l’aide de trois méthodes de mesure des flux en forage sont cohérents : mesure du flux à hélices, mesure du flux par impulsion de chaleur et mesure par dilution. En conditions naturelles, le système apparaît plus compliqué. De manière plus spécifique, dans la moitié supérieure du forage, la mesure du flux à hélices indiquait des flux descendants, la mesure du flux par impulsion de chaleur des flux ascendants négligeables alors que la méthode par dilution montrait une dilution significative. La raison évoquée était celle de flux croisés au dessus de la cote de 29m. L’analyse des données de descente et de remontée du niveau piézométrique ainsi que l’analyse développée par Drost concernant les méthodes de forage unique, ont permis d’estimer les transmissivités de l’aquifère : 2,049, 2,928 et > 43,88 m2/jour respectivement. La divergence entre les données issues des analyses des descentes et des remontées était attribuée aux pertes de charge hydraulique non linéaires associées aux écoulements turbulents et à des effets d’inertie. La différence entre les résultats des essais de pompage et des résultats de l’analyse de Drost était expliquée par les flux au cours de l’essai hydraulique par pompage qui contourne la zone située à 29 m comme mentionné auparavant.

Análisis de procesos de flujo en creta fracturada bajo condiciones de bombeo y ambientales (Reino Unido)

Resumen

Un conjunto integrado de distintas mediciones han sido usados para estudiar el comportamiento del agua subterranean en un pozo de observación en una formación de roca fracturada, el UK Chalk, bajo condiciones de bombeo y ambientales. Bajo condiciones de bombeo la respuesta de la perforación abierta fue relativamente consecuente con el flujo principalmente concentrado a lo largo de cuatro horizontes discretos de flujo. Más aún se observó una excelente correspondencia entre los tres métodos de mediciones de velocidad de flujo en la perforación: flujímetro de turbina, flujímetro de pulso de calor y pruebas de dilución. Bajo condiciones ambientales el sistema aparecía más complicado. Específicamente, en la mitad superior de la perforación el flujímetro de turbina mostró un flujo importante descendente y el flujímetro de pulso de calor mostró un flujo ascendente casi despreciable mientras que la prueba por dilución indicó una dilución significativa. Se concluyó que esto fue debido a la existencia de un flujo cruzado sobre los 29 m superiores. Los análisis de los datos de depresión, datos de recuperación y un análisis de Drost de los datos de flujo cruzado ambientales arrojaron valores estimados de la transmisividad del acuífero de 2,049, 2,928 y > 4,388 m2/día respectivamente. La discrepancia entre la estimación de la depresión y la recuperación fue atribuida a pérdidas de cargas hidráulicas no lineales asociadas con efectos de turbulencia e inerciales. La diferencia entre los ensayos de bombeo y los resultados de Drost fue explicado por el desvío del flujo en los 29 m de región rocosa, mencionados previamente, durante el ensayo de bombeo.

抽水和自然条件下水流在英国裂隙白垩岩中流动过程分析

摘要:

在抽水和自然条件下, 对英国白垩岩裂隙岩层中的一口观测井进行了一系列不同的测量, 以研究其地下水的行为。在抽水条件下, 开放钻孔的响应基本与主要集中在四个分散的水流层的水流一致。此外, 叶轮流速计、热脉冲流速计和稀释法试验三种钻孔流速测量方法呈现出很好的一致性。在自然条件下, 系统表现得更为复杂。特别是在钻孔的上半部, 叶轮流速计表明水流为下降流, 热脉冲流速计表明其为可以忽略的上升流, 而稀释法试验则表明存在着显著的稀释作用。这是由于在上面的29m发生了横向流。降深数据和恢复试验数据分析以及环境横向流数据的Drost分析分别给出含水层的导水系数约为2,049, 2,928 和大于 4,388 m2/d。两种方法给出的导水系数的不同是与紊流和惯性效应有关的非线性水头损失导致的。而抽水试验中水流绕过了前述29 m区域解释了抽水试验和Drost结果之间的不同。

Análise de processos de escoamento em calcários orgânicos porosos (cré) fracturados sob condições ambientais e em bombagem (Reino Unido)

Resumo

Foi utilizado um conjunto integrado de diferentes medições para estudar o comportamento das águas subterrâneas num furo de observação numa formação de rocha fracturada, o cré da formação “Chalk” do Reino Unido, sob condições ambientais e em bombagem. Sob condições de bombagem a resposta do furo foi relativamente linear, com o fluxo concentrado principalmente ao longo de quatro horizontes de fluxo discretos. Além disso, foi observada uma correspondência excelente entre os três métodos de medição da velocidade de escoamento no furo: micromolinete, caudalímetro de impulso térmico, e teste de diluição. Sob condições ambientais o sistema parece mais complicado. Especificamente, na metade superior do furo, o micromolinete mostrou fluxo descendente substancial e o caudalímetro de impulso térmico mostrou fluxo ascendente quase desprezável, enquanto o teste de diluição indicou diluição significativa. Concluiu-se que esta situação se devia a fluxos cruzados que ocorrem nos 29 m superiores. A análise de dados de rebaixamento, dos dados de recuperação, e uma análise Drost dos dados de fluxo-cruzado em condições ambientais, conduziram a estimativas de transmissividade do aquífero de 2,049, 2,928 e > 4,388 m2/dia, respectivamente. A discrepância entre as estimativas para os rebaixamentos e para a recuperação foi atribuída a perdas de carga não lineares associadas a turbulência e efeitos de inércia. A diferença entre o ensaio de bombagem e os resultados Drost foi explicada pelo facto do fluxo, durante o ensaio de bombagem, contornar a zona supracitada de 29 m de rocha.

Notes

Acknowledgements

Funding through the NERC LOCAR research program is gratefully acknowledged (project NER/T/S/2001/00941). The authors would like to thank T. Scott at the Environment Agency, UK, for access to and use of the Bottom Barn abstraction well. The assistance of L. Maurice, D. Buckley, and I. Woods from the British Geological Survey for help in collecting the field data is also gratefully acknowledged.

References

  1. Agarwal RG (1980) A new method to account for producing time effects when drawdown type curves are used to analyze pressure buildup and other test data. SPE Paper 9289 presented at the 55th SPE Annual Technical Conference and Exhibition, 21–24 September, Dallas, TX, USAGoogle Scholar
  2. Allen DJ, Brewerton LJ, Coleby LM, Gibbs BR, Lewis MA, MacDonald AM, Wagstaff SJ, Williams AT (1997) The physical properties of major aquifers in England and Wales. British Geological Survey Technical Report WD/97/34, BGS, Keyworth, UKGoogle Scholar
  3. Bidaux P, Tsang CF (1991) Fluid flow patterns around a well bore or an underground drift with complex skin effects. Water Resour Res 27(11):2993–3008CrossRefGoogle Scholar
  4. Doughty C (2005) Signatures in flowing fluid electric conductivity logs. J Hydrol 310:157–180CrossRefGoogle Scholar
  5. Drost W, Klotz D, Koch A, Moser H, Neumaier F, Rauert W (1968) Point dilution methods of investigating ground water flow by means of radioisotopes. Water Resour Res 4(1):125–146CrossRefGoogle Scholar
  6. Dudgeon CR, Green MJ, Smedmor WJ (1975) Heat-pulse flowmeter for boreholes: Medmenham. Technical Report TR4. Water Research Centre, Swindon, UKGoogle Scholar
  7. ENTEC (2005) A comparison of Chalk groundwater models in and around the River Test Catchment. Report PP-925, ENTEC, Calgary, AB, CanadaGoogle Scholar
  8. Evans DG (1995) Inverting fluid conductivity logs for fracture inflow parameters. Water Resour Res 31(12):2905–2916CrossRefGoogle Scholar
  9. Giorgi T (1997) Derivation of the Forchheimer law via matched asymptotic expansions. Transp Porous Media 29(2):191–206CrossRefGoogle Scholar
  10. Glossop K, Lisboa PJG, Russel PC, Siddans A, Jones GR (1999) An implementation of the Hough transformation for the identification and labelling of fixed period sinusoidal curves. Comput Vis Image Underst 74(1):96–100CrossRefGoogle Scholar
  11. Harker D (1974) Groundwater scheme stage 1: pumping test at Bottom Barn SU57/151. Ground Water Section, TCD, Thames Water Authority, Reading, UKGoogle Scholar
  12. Hartmann S, Odling NE, West LJ (2007) A multi-directional tracer test in the fractured Chalk aquifer of E. Yorkshire, UK. J Contam Hydrol 94:315–331CrossRefGoogle Scholar
  13. Hvorslev MJ (1951) Time lag and soil permeability in groundwater observations, Bull 36, Waterw. Exp. Station, US Army Corps of Eng., Vicksburg, MIGoogle Scholar
  14. Jacob CE (1947) Drawdown test to determine effective radius of artesian well. Trans Am Soc Civil Eng 112:1047–1070Google Scholar
  15. James SC, Jepsen RA, Beauheim RL, Pedler WH, Mandell WA (2006) Simulations to verify horizontal flow measurements from a borehole flowmeter. Ground Water 44(3):394–405CrossRefGoogle Scholar
  16. Karasaki K, Freifeld B, Cohen A, Grossenbacher K, Cook P, Vasco D (2000) A multidisciplinary fractured rock characterization study at Raymond Field Site, Raymond, California. J Hydrol 236(1–2):17–34Google Scholar
  17. Le Borgne T, Paillet F, Bour O, Caudal JP (2006) Cross-borehole flowmeter tests for transient heads in heterogeneous aquifers. Ground Water 44(3):444–452CrossRefGoogle Scholar
  18. Liu Y, Gupta HV (2007) Uncertainty in hydrologic modeling: toward an integrated data assimilation framework. Water Resour Res 43:W07401CrossRefGoogle Scholar
  19. MacDonald AM, Allen DJ (2001) Aquifer properties of the Chalk of England. Q J Eng Geol 34:371–384Google Scholar
  20. Mathias SA, Butler AP (2007) Shape factors for constant-head double packer permeameters. Water Resour Res 43, W06430CrossRefGoogle Scholar
  21. Mathias SA, Butler AP, Peach DW, Williams AT (2007) Recovering tracer test input functions from fluid electrical conductivity logging in fractured porous rocks. Water Resour Res 43, W07443CrossRefGoogle Scholar
  22. Mathias, SA, Butler, AP, Zhan, H (2008) Approximate solutions for Forchheimer flow to a well. J Hydraul Eng-ASCE 134:1318–1325Google Scholar
  23. Meier PM, Carrera J, Sanchez-Vila X (1998) An evaluation of Jacob’s method for the interpretation of pumping tests in heterogeneous formations. Water Resour Res 34(5):1011–1025CrossRefGoogle Scholar
  24. Michalski A, Klepp GM (1990) Characterization of transmissive fractures by simple tracing of in-well flow. Ground Water 28(2):191–198CrossRefGoogle Scholar
  25. Mortimore RN (1986) Stratigraphy of the Upper Cretaceous White Chalk of Sussex. Proceedings of the Geologists’ Association, London, vol 97, 1986, pp 97–139Google Scholar
  26. Nativ R, Adar E, Assaf L, Nygaard E (2003) Characterization of the hydraulic properties of fractures in chalk. Ground Water 41(4):532–543CrossRefGoogle Scholar
  27. Paillet FL, Pedler WH (1996) Integrated borehole logging methods for wellhead protection applications. Eng Geol 42:155–165CrossRefGoogle Scholar
  28. Price M, Williams AT (1993) A pumped double-packer system for use in aquifer evaluation and groundwater sampling. Proc Inst Civ Eng 2 101:85–92Google Scholar
  29. Price M, Morris B, Robertson A (1982) A study of intergranular and fissure permeability in Chalk and Permian aquifers, using double-packer injection testing. J Hydrol 54:401–423CrossRefGoogle Scholar
  30. Rawson PF, Allen P, Gale AS (2001) The Chalk Group revised lithostratigraphy. Geoscientist 11:21Google Scholar
  31. Robinson ND (1986) Lithostratigraphy of the Chalk Group of the North Downs, southeast England. Proceedings of the Geologists’ Association, vol 97, London, 1986, pp 141–170Google Scholar
  32. Rushton KR, Booth SJ (1976) Pumping-test analysis using a discrete time–discrete space numerical method. J Hydrol 28:13–27CrossRefGoogle Scholar
  33. Rushton KR, Chan YK (1976) Pumping test analysis when parameters vary with depth. Ground Water 14:82–87CrossRefGoogle Scholar
  34. Rushton KR, Connorton BJ, Tomlinson LM (1989) Estimation of the ground water resources of the Berkshire Downs supported by mathematical modelling. Q J Eng Geol 22:329–341CrossRefGoogle Scholar
  35. Samani N, Pasandi M (2003) A single recovery type curve from Theis’ exact solution. Ground Water 41(5):602–607CrossRefGoogle Scholar
  36. Schurch M, Buckley D (2002) Integrating geophysical and hydrochemical borehole-log measurements to characterize the Chalk aquifer, Berkshire, United Kingdom. Hydrogeol J 10:610–627CrossRefGoogle Scholar
  37. Shapiro AM, Oki DS, Green EA (1998) Estimating formation properties from early-time recovery in wells subject to turbulent head losses. J Hydrol 208:223–236CrossRefGoogle Scholar
  38. Su GW, Freifeld BM, Oldenburg CM, Jordan PD, Daley PF (2006) Interpreting velocities from heat-based flow sensors by numerical simulation. Ground Water 44(3):386–393CrossRefGoogle Scholar
  39. Tsang CF, Doughty C (2003) Multirate flowing fluid electric conductivity logging method. Water Resour Res 39(12):1354CrossRefGoogle Scholar
  40. Tsang CF, Hufschmeid P, Hale FV (1990) Determination of fracture inflow parameters with a borehole fluid conductivity logging method. Water Resour Res 26(4):561–578CrossRefGoogle Scholar
  41. Wheater HS, Peach DW (2004) Developing interdisciplinary science for integrated catchment management: the UK LOwland CAtchment Research (LOCAR) Programme. Int J Water Resour Dev 20:369–385CrossRefGoogle Scholar
  42. White HJO (1907) The geology of the country around Hungerford and Newbury. Memoir, British Geological Survey, Keyworth, UKGoogle Scholar
  43. Williams JH, Paillet FL (2002) Using flowmeter pulse tests to define hydraulic connections in the subsurface: a fractured shale example. J Hydrol 265:100–117CrossRefGoogle Scholar
  44. Williams A, Bloomfield J, Griffiths K, Butler A (2006) Characterising the vertical variations in aquifer properties within the Chalk aquifer. J Hydrol 330:53–62CrossRefGoogle Scholar
  45. Woods MA, Aldiss DT (2004) The stratigraphy of the Chalk Group of the Berkshire Downs. Proc Geol Assoc 115:249–265CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • A. P. Butler
    • 1
  • S. A. Mathias
    • 1
  • A. J. Gallagher
    • 2
  • D. W. Peach
    • 2
  • A. T. Williams
    • 2
  1. 1.Department of Civil and Environmental EngineeringImperial College LondonLondonUK
  2. 2.British Geological SurveyWallingfordUK

Personalised recommendations