| Abstract: | Two alternative conceptual models of the physical processes controlling seawater intrusion in a coastal basin in California, USA, were tested to identify a likely principal pathway for seawater intrusion. The conceptual models were tested by using a two-dimensional, finite-element groundwater flow and transport model. This pathway was identified by the conceptual model that best replicated the historical data. The numerical model was applied in cross section to a submarine canyon that is a main avenue for seawater to enter the aquifer system underlying the study area. Both models are characterized by a heterogeneous, layered, water-bearing aquifer. However, the first model is characterized by flat-lying aquifer layers and by a high value of hydraulic conductivity in the basal aquifer layer, which is thought to be a principal conduit for seawater intrusion. The second model is characterized by offshore folding, which was modeled as a very nearshore outcrop, thereby providing a shorter path for seawater to intrude. General conclusions are that: 1) the aquifer system is best modeled as a flat, heterogeneous, layered system; 2) relatively thin basal layers with relatively high values of hydraulic conductivity are the principal pathways for seawater intrusion; and 3) continuous clay layers of low hydraulic conductivity play an important role in controlling the movement of seawater. |
| Genre: | Article |
| ProdID: | 70019912 |
| Citation Author: | Nishikawa, T. |
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| Citation End Page: | 74 |
| Citation Issue: | 3 |
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| Citation Language: | English |
| Citation Larger Work Title: | Hydrogeology Journal |
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| Citation Number Of Pages: | 15 |
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| Citation Search Results Text: | Testing alternative conceptual models of seawater intrusion in a coastal aquifer using computer simulation, southern California, USA; 1997; Article; Journal; Hydrogeology Journal; Nishikawa, T. |
| Citation Start Page: | 60 |
| Citation Volume: | 5 |
| Citation Year: | 1997 |
| Type: | citation/reference |
| Text: | Testing alternative conceptual models of seawater intrusion in a coastal aquifer using computer simulation, southern California, USA; 1997; Article; Journal; Hydrogeology Journal; Nishikawa, T. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Wed, 1 Jan 1997 00:00 -0600 |
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