Journal of Geology & Geophysics
Open Access
ISSN: 2381-8719
+44 1478 350008
ISSN: 2381-8719
+44 1478 350008
Bill X Hu
Keynote: J Geol Geosci
Groundwater flow cycling in the Spring Creek spingshed and interaction between groundwater and seawater in the spring sub ground conduit is numerically simulated using the CFPv2, the latest research version of MODFLOW-CFP (Conduit Flow Process). Spring Creek Springs and Wakulla Spring located in a marine estuary and 11 miles inland respectively are two major groundwater discharge spots in the Woodville Karst Plain (WKP), North Florida, USA. A conceptual model for three repeating phases of groundwater flow cycle between the two springs and recharge from a major surface creek (Lost Creek) was proposed from a low rainfall period to a heavy rainfall period then back to a low rainfall period. Tracer tests and cave diving found a complex sub ground Karst conduit network connect the two springs. The flow rate, salinity and sea level at the Spring Creek Springs could significantly affect freshwater discharge and water stage at Wakulla Spring simultaneously. Based on the conceptual model, the groundwater flow model is developed using CFPv2 and calibrated by field measurements. Non-laminar flow, direct recharges in conduits, time-variable water stage at the submarine spring and flow exchange between conduits and porous medium are implemented in the numerical model. The developed numerical model is used to simulate the seawater intrusion and fresh groundwater contamination through the submarine springā??s conduit and its influence on the inland spring discharge from June 2007 to June 2010. Simulated results of two springā??s discharges match reasonably well with measurements and quantitatively present the three-phase groundwater flow cycling. The regional flow field and relationship between inland spring and submarine spring are studied and evaluated as well in a prediction of sea level rise.
Bill X Hu is the Professor of the Department of Earth, Ocean & Atmospheric Science at Florida State University. He is also the Adjunct Faculty Member of the Department of Geosciences at Nanjing University. He has done his Ph.D. from Purdue University in the year of 1996. He has more than 45 publications in many Journals.