深圳玉律高温热泉成因及对罗铁输水隧洞工程影响分析

Analysis of the genesis of the Yulyu high-temperature hot spring in Shenzhen and its impact on the Luotian-Tiegang Water Conveyance Tunnel Project

摘要

深圳罗田水库—铁岗水库输水隧洞沿线地质条件复杂，输水隧洞干线临近玉律中高温热泉，热泉流量约1.5 L/s,最高温度66~68℃,热泉的成因尚未完全厘清，热泉与隧洞工程建设是否相互影响需要重点研究。采用地面物探、钻孔、地温测试、水化学和同位素测试等多种手段，分析了玉律中高温热泉的成因，评价了热泉对隧洞工程建设可能存在的影响，隧洞开挖验证了分析评价正确合理性。结果表明，地下热水来源于大气降水，补给高程位于102~169 m,判定补给区位于热泉南侧的低山丘陵区北坡，夹持于玉律断层南盘和黄草坑顶断层北盘之前的花岗岩地区；热泉补给水源沿次级断层和裂隙密集带向深部循环，受热对流沿玉律断层上升至地表构造薄弱部位出露成热泉；罗铁输水隧洞线路避开了玉律热泉补径排深循环渗流场，工程建设受玉律热泉及其地热影响小，也不会对玉律热泉产生影响。

Abstract

The geological conditions along the Luotian Reservoir-Tiegang Reservoir water conveyance tunnel in Shenzhen are complex. The main tunnel line is adjacent to the Yulyu medium-to-high-temperature hot spring, which has a flow rate of approximately 1.5 L/s and a maximum temperature of 66~68℃. The genesis of the hot spring remains unclear, and the potential mutual impacts between the hot spring and tunnel construction require focused study. By employing surface geophysical prospecting, drilling, geothermal temperature testing, hydrochemical and isotopic analyses, this study investigates the formation mechanism of the Yulyu hot spring and evaluates its potential impacts on the tunnel project. The tunnel excavation validated the accuracy of the analytical result. The findings indicate that the geothermal water originates from atmospheric precipitation, with a recharge elevation of 102-169 m. The recharge area is identified as the northern slope of a low hilly region south of the hot spring, situated within a granite zone bounded between the southern plate of the Yulyu Fault and the northern plate of the Huangcaokengding Fault. The recharge water circulates deeply along secondary faults and fracture-dense zones, ascends via thermal convection along the Yulyu Fault, and emerges at structurally weak surface locations to form the hot spring. The Luotian-Tiegang water conveyance tunnel route avoids the deep cyclic seepage field of the Yulyu hot spring's recharge, flow, and discharge pathways. The project construction exhibits minimal impact from the Yulyu hot spring and its geothermal activity, nor does it adversely affect the hot spring itself.

关键词

深圳玉律热泉 / 地热 / 氢氧同位素 / 罗铁输水隧洞

Key words

Yulyu hot spring in Shenzhen / geothermal / hydrogen and oxygen isotopes / Luotian-Tiegang Water Conveyance Tunnel

基金资助

长江勘测规划设计研究有限责任公司自主创新项目“复杂地质条件下水工深埋长隧洞涌水突泥防治关键技术研究”(CX2023Z02-1)