Development and application of a regional land subsidence model for the plain of Tianjin

Abstract

In this paper, a coupled numerical groundwater and land subsidence model was developed for the Tianjin Plain. The model was employed to investigate the groundwater resources and their changes over the last decade, and to further predict the changing patterns of the groundwater level and associated land subsidence in future. First, according to the regional hydrogeology, the simulation area was defined with an area of 10.6×10³ km², which was divided into six aquifer units. A coupled groundwater and land subsidence numerical model was built by using Modflow2005 and the land subsidence simulation module SUB (subsidence and aquifer-system compaction), in which the groundwater flow was modeled as three-dimensional unsteady flow and the land subsidence simulation was based on one-dimensional consolidation theory. The model was then calibrated by using the groundwater level contour lines, hydrographs, and land subsidence hydrographs over the period of 1998–2008. In addition, groundwater balance analysis of the simulation period indicated that under multi-year groundwater withdrawal condition the cross-flow recharge, compression release, and lateral boundary inflow contributed 44.43%, 32.14%, and 21.88% to the deep aquifer recharge, respectively. Finally, the model was applied to predict the changing patterns of the groundwater levels and the associated variations in land subsidence under the control of groundwater exploitation after implementation of the south-to-north water diversion project. The simulation results demonstrated that the groundwater level may gradually increase year by year with an decrease in the groundwater withdrawal; and the land in dominated land subsidence regions including the urban area, Dagang, Hangu, Jinghai, Wuqing, and Jinnan, may rebound at an average rate of 2–3 mm/a, and the land subsidence rate in the other regions may decrease.

Keywords

groundwater / land subsidence / simulation / modflow / SUB / the south-to-north water diversion

References

[1] Alley W M, Healy R W, LaBaugh J W, . Flow and Storage in Groundwater Systems. Science, 2002, 296(5575): 1985-1990.

[2] Biot M A. General Theory of Three-Dimensional Consolidation. Journal of Applied Physics, 1941, 12(2): 155-164.

[3] Carslaw H S, Jaeger J C. Conduction of Heat in Solids, 1959 Oxford: Oxford University Press, 510.

[4] Cui X D. Application and Development of MODFLOW and IDP in Digital Calculation of Land Subsidence in Tianjin. The Chinese Journal of Geological Hazard and Control, 1998, 9(2): 122-128.

[5] Deverel S J, Leighton D A. Historic, Recent, and Future Subsidence, Sacramento-San Joaquin Delta, California, USA. San Francisco Estuary and Watershed Science, 2010, 8(2): 1-23.

[6] Dong S C, Yin H W, Yao S P, . Detecting Surface in Coal Mining Area Based on InSAR Technique. Journal of Earth Science, 2013, 24(3): 449-456.

[7] Guo Z R, Qu H L, Cui X D, . Study of Numerical Simulation of Land Subsidence in Tianjin. Acta Geoscientica Sinica, 1998, 19(4): 415-422.

[8] Harbaugh A W. MODFLOW-2005, The U.S. Geological Survey Modular Ground-Water Model-The Ground-Water Flow Process. U.S. Geological Survey Techniques and Methods, 2005, 6-A16 253.

[9] Helm D C. One-Dimensional Simulation of Aquifer System Compaction Near Pixley, California 1. Constant parameters. Water Resour. Res., 1976, 12(3): 375-391.

[10] Hoffmann J, Leake S A, Galloway D L, . MODFLOW-2000 Ground-Water Model-User Guide to the Subsidence and Aquifer-System Compaction (SUB) Package. U.S. Geological Survey Open-File Report, 2003, 3-233.

[11] Ji Y D, Chai X Z, Liu Q S, . Current Situation and Existing Problems of Numerical Simulation of Groundwater Flow in a Large-Scale Area. Coal Geology & Exploration, 2009, 37(5): 32-36.

[12] Lewis R W, Schrefler B. A Fully Coupled Consolidation Model of the Subsidence of Venice. Water Resour. Res., 2007, 14(2): 223-230.

[13] Li C Z, Zhou Z F. Review of Numerical Calculation Models for Land Subsidence and Fluid-Solid Coupling Theory. Site Investigation Science and Technology, 2006, 6: 14-20.

[14] Li W Y, Cui Y L, Su C, . A Study on an Integrated Numerical Groundwater and Land Subsidence Model of Tianjin. Journal of Jilin University (Earth Science Edition), 2012, 42(3): 805-813.

[15] O’ Sullivan, M., Yen, A., Clearwater, E., 2010. Three-Dimensional Model of Subsidence at Wairakei-Tauhara. Auckland UniServices Limited, 85

[16] Ortega-Guerrero A, Rudolph D L, Cherry J A. Analysis of Long-Term Land Subsidence Near Mexico City: Field Investigation and Predictive Modeling. Water Resour. Res., 1999, 35(11): 3327-3341.

[17] Ran Q Q, Gu X Y. A Coupled Model for Land Subsidence Computation with Consideration of Rheological Property. The Chinese Journal of Geological Hazard and Control, 1998, 9(2): 99-103.

[18] Riley F S. Analysis of Borehole Extensometer Data from Central California. International Association of Scientific Hydrology Publication, 1969, 89: 423-431.

[19] Shearer T R. A Numerical Model to Calculate Land Subsidence, Applied at Shanghai in China. Engineering Geology, 1998, 49(2): 85-93.

[20] Terzaghi K. Principles of Soil Mechanics IV-Settlement and Consolidation of Clay. Engineering News-Record, 1925, 95(3): 874-878.

[21] Tianjin Municipal Water Conservation Bureau Groundwater Development Plan of Water Supply Area of South-to-North Water Diversion Project in Tianjin City, 2003

[22] Wang J B, Li P. Composition of Groundwater Resources in Deep-Seated Aquifers under the Condition of Land Subsidence in Tianjin Plain. Hydrogeology & Engineering Geology, 2004, 31(5): 35-37.

[23] Wang J B, Wang Y B, Zhang H T. Sustainable Development of the Deep Groundwater Resources under the Condition of Controlling Land Subsidence in Tianjin. Hydrogeology & Engineering Geology, 2007, 34(4): 74-78.

[24] Wang Y B. Achievement Report (Tianjin) of Investigation and Evaluation on Groundwater Sustained Development in Huabei Plain. Tianjin Institute of Geological Survey, Tianjin., 2007, 128-130.

[25] Wu J C, Shi X Q, Ye S J, . Numerical Simulation of Yiscoelastoplastic Land Subsidence due to Groundwater Overdrafting in Shanghai, China. Journal of Hydrologic Engineering, 2010, 15(3): 223-236.

[26] Xu M, Wang W, Yu Q. Ground Water and Land Subsidence Optimum Controlling Numerical Simulation in Tianjin Binhai New Area. Urban Geology, 2010, 5(1): 11-16.

[27] Xue Y Q, Wu J C, Zhang Y, . Simulation of Regional Land Subsidence in the Southern Yangtze Delta. Sci. China. Ser. D: Earth Sci., 2008, 51(6): 808-825.

[28] Xue Y Q, Xie C H. Numerical Simulation for Groundwater, 2007 Beijing: Science Press, 43.

[29] Xue Y Q, Zhang Y, Ye S J, . Land Subsidence in China. Environ. Geol., 2005, 48(6): 713-720.

[30] Ye S J, Xue Y Q, Wu J C, . Land Subsidence Modeling Based on the Modified Merchant Model: A Case Study of Shanghai. Journal of Nanjing University (Natural Sciences), 2011, 47(3): 291-298.

[31] Yu Q, Wang W, Yi C R. Design and Application of an Automatic System for Land subsidence and Water Table Monitoring in Tianjin City. Groundwater, 2007, 29(5): 101-104.

[32] Zhang Z, Hong F, Chen Z, . Investigation and Assessment of Sustainable Utilization of Groundwater Resources in the North China Plain, 2009 Beijing: Geological Press

[33] Zhang L Y. Using Hydrochemistry and Strontium Isotopes to Identify the Sources of Salt in Groundwater Waters of the Tianjin Coastal Area: [Dissertation], 2012 Tianjin: Tianjin Normal University, 25.

[34] Zhou Y X, Li W P. Modelling of Regional Groundwater Flow. Hydrogeology & Engineering Geology, 2009, 1-10.