Tritium Concentrations and Radiocarbon Ages of Gushing Groundwater from Hsuehshan Tunnel, Northern Taiwan
Resource
Terrestrial, Atmospheric and Oceanic Sciences 16 (4): 909-917
Journal
Terrestrial Atmospheric and Oceanic Sciences
Pages
909
Date Issued
2005
Date
2005
Author(s)
劉聰桂
陳正宏
楊燦堯
李民
Abstract
Several serious groundwater outbursts occurred during excavation of the Hsuehshan Tunnel in northern Taiwan. In order to better understand the hydrological characteristics of the rock formations overlying the tunnel, tritium ( 3 H ) concentrations and radiocarbon ( 14 C) ages of groundwater samples from the tunnel were measured. Samples from the gently dipping and less fractured sandstone/shale beds of the Makang Formation to the west have 3 H content of less than 0.6 TU and conventional 14 C ages of older than 8400 yrBP, suggesting pre-bomb recharge and relatively low flow rates ( 8 m yr 1 -). In contrast, samples from the highly fractured and steeply dipping Szeleng meta-sandstone to the east have 3 H contents of 1.2~2.5 TU and conventional 14 C ages of younger than 7400 yrBP, implying origin of post-1999 recharge and higher flow rates of 130~500 m yr 1 -. Tritium and carbon isotopes concentrations reflect local hydrogeological characteristics of the rock formations along the Hsuehshan Tunnel and were helpful in assessing excavation methods.
SDGs
Type
journal article
File(s)![Thumbnail Image]()
Loading...
Name
16.pdf
Size
604.78 KB
Format
Adobe PDF
Checksum
(MD5):399df50083faf64cbb05b8824ffdd455