Locating and characterising groundwater storage areas within an alpine watershed using time‐lapse gravity, GPR and seismic refraction methods
Locating and characterising groundwater storage areas within an alpine watershed using time‐lapse gravity, GPR and seismic refraction methods
复制标题
使用延时重力、探地雷达和地震折射方法定位和描述高山流域内的地下水储存区域
DOI：
10.1002/hyp.9316
复制
发表时间：
2012
影响因子：
3.2
通讯作者：
J. Liard
中科院分区：
文献类型：
--
作者：
A. McClymont;M. Hayashi;L. Bentley;J. Liard
高山流域未固结的沉积物可以将冰川融化和融雪储存为地下水，这有助于在干旱时期维持山区河流的流动。然而，在崎岖的高山地形中，地下水储量的数量和分布还不清楚，这阻碍了我们预测地下水进入高山河流的速度和时间的能力。我们展示了如何使用非侵入性时移微重力测量来测量加拿大落基山脉奥哈拉湖高山流域的一个大型（约1500 × 1000米）冰碛土场内地下水储量变化的空间分布。额外的探地雷达（GPR）和地震折射测量提供了地下基岩地形的补充信息，并揭示了一个主要的西北-东南走向的洼地的位置，该洼地可能控制着地下水流向与冰碛石-距地相连接的高山湖泊。2009年和2010年夏季，在冰碛石场及其周围的80个重力站网络上进行的重复相对重力测量显示，重力变化高达25 μ gal。尽管与地下水流出库区有关的微小重力变化是嘈杂的，但在冰碛石-土积区东侧变化明显。©加拿大女王陛下2012。
Unconsolidated sediments in alpine watersheds can store glacier melt and snowmelt as groundwater, which helps sustain flow in mountain rivers during dry periods. However, the amount and distribution of groundwater storage in rugged alpine terrain is not well understood, hindering our ability to predict the rate and timing of groundwater discharge into alpine streams. We show how non‐invasive time‐lapse microgravity surveys can be used to gauge the spatial distribution of groundwater storage changes within a large (ca 1500 × 1000 m) moraine–talus field of the Lake O'Hara alpine watershed of the Canadian Rockies. Additional ground‐penetrating radar (GPR) and seismic refraction surveys provide complementary information on subsurface bedrock topography and reveal the location of a major northwest–southeast trending depression that likely controls groundwater flow to an alpine lake contiguous with the moraine–talus field. Repeat relative gravity measurements made on a network of 80 gravity stations over and around the moraine–talus field during the summers of 2009 and 2010 reveal gravity changes of up to 25 µgal. Although the small gravity changes associated with groundwater flowing out of storage areas are noisy, significant changes are evident on the eastern side of the moraine–talus field. © Her Majesty the Queen in Right of Canada 2012.