An Analytical Solution for Tidal Fluctuations in Heterogeneous Coastal Leaky Aquifer Systems

• Main Authors: Li, Guo-Hao, 李國豪
• Other Authors: Yeh, Hund-Der
• Format: Others
• Language: en_US
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/21850957642300260287

碩士 === 國立交通大學 === 環境工程系所 === 99 === The coastal leaky aquifer system includes an unconfined aquifer on the top, a confined aquifer at the bottom, and an aquitard in between. This aquifer system was usually assumed to be homogeneous and of an infinite extent in the horizontal direction. The aquifer system may however be heterogeneous due to depositional and post depositional processes. This study considers that the aquitard and confined aquifer are heterogeneous and both formations are divided into several homogeneous regions. A one-dimensional analytical model is developed for describing the head fluctuation in such a heterogeneous leaky aquifer system. The water table of the upper unconfined aquifer is maintained constant. It is revealed that both the length increasing and location nearing coast line of the heterogeneous aquitard have significant decreasing on the amplitude and increasing phase shift of the head fluctuation in the confined aquifer. Besides, this study indicates a heterogeneous trending confined aquifer may probably cause a shorter tidal intrusion distance and lower head distribution in a coastal leaky aquifer system.