Piezometric surface of principal artesian aquifer in coastal area of Georgia, December 1966

1968 ◽  
Author(s):  
R.L. Wait ◽  
D.O. Gregg
1970 ◽  
Vol 7 (2) ◽  
pp. 194-204 ◽  
Author(s):  
R. N. Farvolden ◽  
J. P. Nunan

Realignment of the Welland Canal between Port Robinson and Port Colborne and the building of underpass structures necessitated both temporary and permanent depressurizing of an artesian aquifer. The aquifer is a thin zone of fractured dolomite found immediately beneath approximately 60 to 100 ft (18 to 30 m) of poorly-permeable glacial till and lacustrine sediments. Since most of the private wells in the Welland area obtain water from the bedrock aquifer, extensive well interference problems were anticipated. Problems in connection with the dewatering and depressurizing included design of deep-well pumping systems for excavation work, prediction and monitoring of drawdown effects, and the determination of responsibility for interference in specific areas since several dewatering systems with overlapping cones-of-depression would be operating simultaneously. To overcome a problem of insufficient hydrologic data prior to the commencement of dewatering, a contour map of the original piezometric surface was constructed from drillers' records. This map showed a normal groundwater flow system where the movement of groundwater was from local upland recharge areas to local discharge areas along the Welland River and the existing canal. A contour map of the drawdown was drawn on the assumption that deviations from the reconstructed original piezometric surface were caused by dewatering. Analysis of the cone-of-depression along with analyses of pre-engineering pumping tests provided values for aquifer coefficients required for solution of the unsteady flow equations. Because the coefficients used were average values for a relatively small area extrapolated over a broad area, the predicted drawdown showed considerable variation in reliability. The work did provide, however, a check on the numerical method (Frind 1970) which takes into account local variations.


SIMBIOSA ◽  
2014 ◽  
Vol 3 (1) ◽  
Author(s):  
Yarsi Efendi ◽  
Dahrul Aman Harahap

Structure and physiognomy of mangrove strongly influenced by the zonation that occurred in the area of mangroves growth. The differences of zona growth will effect  to differences in the structure and composition of vegetation. There are three zones in the mangrove area, which is caused by the difference of flooding which also resulted in the difference to the salinity. The differences of growth zone will performed to the type vegetation performance (Physiognomy). This study is aims to prove the mangrove’s physiognomy that taken in the coastal area of Rempang Cate  Batam, on March 2014 to June 2014. This study was a survey with data collection using a vertical transect plots 100 m. Based on the research that has been done obtained difference vegetation physiognomy stands for every level of growth in each zone growth. Proximally found 13 species of mangroves in 8 families. The results of the analysis of the vegetation on the trees growth level are, Ceriops decandra have the greatest significance important value 167.55% on sapling (juvenille ) level is dominated by Rhizophora apiculata 120%, and seedling growth level dominated by Rhizophora apiculata  186.80%. Keywords: Structure and physiognomy, mangrove zonation


2017 ◽  
Vol 10 (1) ◽  
pp. 57-62
Author(s):  
Uihwan KWAK ◽  
Wonkeun JANG ◽  
Inwoo HAN ◽  
Kyounghoon LEE
Keyword(s):  

2012 ◽  
Vol 132 (6) ◽  
pp. 560-567 ◽  
Author(s):  
Megumu Miki ◽  
Toru Miki ◽  
Akira Asakawa ◽  
Takatoshi Shindo ◽  
Shigeru Yokoyama

2011 ◽  
Vol 131 (12) ◽  
pp. 973-978 ◽  
Author(s):  
Fumiyuki Fujii ◽  
Masaru Ishii ◽  
Mikihisa Saito ◽  
Michihiro Matsui ◽  
Daisuke Natsuno

Sign in / Sign up

Export Citation Format

Share Document