Abstract

Many springs occur in and around Pasighat. Eight major springs of the area were considered for the study. These springs are Dimple type, Fault dam type, and a combination of Fault dam and Border type. The highest discharge is 263.23 L/sec and the lowest is 1.91 L/sec. The aquifers are terrace deposits that comprise of unsorted boulders, cobbles and pebbles in sandy matrix and the springs occur at the base of different terrace levels. Due to the scarcity of dug wells or deep tube wells, subsurface investigations were done using vertical electric sounding (VES). VES data generated at six locations show H-type situation. The aquifers are at shallow depth, unconfined, and have good hydrogeological prospects. At the T₂ terrace, volume of water stored is 42,14,512.5 m³ and the combined discharge of springs is 38,257.92 m³/day. These springs are recharged by precipitation and influent streams. Springs of the study area are aligned along the Himalayan Frontal Thrust (HFT) and its splays, and they have a major role in the evolution of these springs. The springs were formed due to topographic breaks and less permeable collapsed debris. Local people use spring water for the household, irrigation, laundry, and fisheries.

Research highlights

1. (i)

   Springs present along the base of the terraces have the highest discharge of 263.23 L/sec.

2. (ii)

   These springs are genetically related to HFT.

3. (iii)

   Terrace aquifers are suitable for groundwater development and groundwater flows from influent streams and foothill regions towards Siang River.

4. (iv)

   Spring water is used by local people for household, irrigation, laundry, and fisheries and proper management of these springs will ensure good supply of water in future.

中文翻译：

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Pasighat的泉水，是社区的宝贵资源：使用地电电阻率技术进行的水文地质研究

摘要

Pasighat及其周边地区有许多温泉。该研究考虑了该地区的八个主要温泉。这些弹簧是酒窝型，断层坝型以及断层坝和边界型的组合。最高排放为263.23 L / sec，最低为1.91 L / sec。含水层是阶地沉积物，由砂质基质中未分类的巨石，鹅卵石和卵石组成，泉水出现在不同阶地水平的底部。由于挖井或深管井的稀缺性，使用垂直电测深仪（VES）进行了地下调查。在六个位置生成的VES数据显示为H型情况。含水层深度较浅，不受限制，具有良好的水文地质前景。在T ₂露台上，储水量为42,14,512.5 m ³泉水的总排放量为38,257.92 m ³ /天。这些泉水因降水和流入水流而得到补充。研究区域的泉水沿喜马拉雅前冲（HFT）及其伸展方向排列，它们在这些泉水的演化中起着重要作用。弹簧是由于地形破裂和渗透性差的塌陷碎屑形成的。当地人将泉水用于家庭，灌溉，洗衣和渔业。

研究重点

1. （一世）

   沿梯田底部出现的弹簧的最高流量为263.23 L / sec。

2. （ii）

   这些弹簧与HFT遗传相关。

3. （iii）

   梯田含水层适用于地下水开发，以及地下水从流入的溪流和山麓地区流向Siang河。

4. （iv）

   当地人将泉水用于家庭，灌溉，洗衣和渔业，对这些泉水的适当管理将确保将来有充足的水供应。