渭河盆地构造热演化对富氦天然气成藏的影响  

Influence of tectonic thermal evolution on the accumulation of helium-rich natural gas in Weihe Basin

作　　者：韩伟 李玉宏 任战利[2] 刘晓晔 周俊林 李成福 HAN Wei;LI Yuhong;REN Zhanli;LIU Xiaoye;ZHOU Junlin;LI Chengfu(Xi’an Geological Survey Center,China Geological Survey(Geosciences Innovation Center of Northwest China),Xi’an 710119,China;Department of Geology,Northwest University,Xi'an 710069,China;Urumqi Branch,Geophysical Institute,BGP,CNPC,Urumqi 830016,China;Geological Survey of Qinghai Province,Xining 810000,China)

机构地区：[1]中国地质调查局西安地质调查中心,西北地质科技创新中心,陕西西安710119 [2]西北大学地质学系,陕西西安710069 [3]中国石油东方地球物理公司研究院乌鲁木齐分院,新疆乌鲁木齐830016 [4]青海省地质调查局,青海西宁810000

出　　处：《天然气地球科学》2025年第3期390-398,共9页Natural Gas Geoscience

基　　金：陕西省自然科学基金面上项目“盆地热演化对壳源氦气富集成藏的控制作用--以渭河盆地为例”(编号:S2024-JC-YB0817);国家重点研发计划“富氦天然气成藏机制及氦资源分布预测技术--复杂地质介质中氦气运聚及富氦气藏封盖机制研究”(编号:2021YFA0719003);中国地质调查局“全国氦气资源潜力评价与战略选区调查”项目(编号:DD20221665)联合资助.

摘　　要：目前,工业开发利用的氦气全部来自于富氦天然气藏中的壳源氦气。天然气为壳源氦气的载体,其生成、成藏与氦气释放均与盆地构造热演化密切相关。系统研究盆地构造热演化对氦气释放的影响对进一步明确天然气与氦气富集成藏有重要意义。渭河盆地作为中国国内首个建立氦气矿权的沉积盆地,氦气资源较为丰富,研究以渭河盆地为例,模拟了盆地构造热演化历史,同时深入分析了烃源岩及氦源矿物的赋存特征,估算了华山岩体主要氦源矿物生成、释放氦气的资源量,探讨了盆地构造热演化对富氦天然气成藏的影响。研究成果可为渭河盆地氦气资源调查评价体系的建立和完善提供新思路。结果表明:①渭河盆地壳源氦气主要来源于富含U、Th元素的榍石、锆石和磷灰石等氦源矿物,其较为分散地分布在岩石中,天然气大量生成和主要氦源矿物释放氦气的温度区间(>180℃)重合度高。②渭河盆地自基底形成后接受了古生代的沉积,随后被强烈抬升剥蚀,大量印支期和燕山期花岗岩岩体在地表成岩,其中富含铀钍元素的氦源矿物(以榍石、锆石和磷灰石为主)不断衰变生成氦气并将部分氦气封闭于矿物晶格中。新生代的断陷作用导致盆地在大约40 Ma以来经历了快速沉降,并在5 Ma左右发生了加速沉降,地层快速升温,古生界烃源岩集中生成天然气,氦源矿物中生成的氦气被集中释放,二者具备时空耦合关系,天然气在运移过程中不断裹挟散布的氦气进入圈闭,从而形成富氦天然气藏。③依据多个含有富氦天然气的盆地中主要氦源矿物对氦封闭温度及氦气成藏的特性,划分出氦封闭带(<60℃)、部分封闭带(60~220℃)和非封闭带(>220℃)。研究成果可为渭河盆地氦气资源调查评价体系的建立和完善提供新思路。At present,all the helium used in industrial development comes from the crustal-derived helium in the helium-rich natural gas reservoir.Natural gas is the carrier of crustal-derived helium,and its generation,accu⁃mulation,and helium release are closely related to the tectonic thermal evolution of the basin.It is important to systematically evaluate the influence of tectonic thermal evolution on the helium release in a basin to clarify the enrichment of natural gas and helium.The Weihe Basin,as the first sedimentary basin with helium mining rights in China,is rich in helium gas resources.This article takes the Weihe Basin as an example to systematical⁃ly simulate the tectonic and thermal evolution history of the basin.At the same time,it deeply analyzes the oc⁃currence characteristics of hydrocarbon source rocks and helium source minerals,estimates the amount of heli⁃um resources generated and released by the main helium source minerals in the Huashan rock mass,and ex⁃plores the impact of basin tectonic and thermal evolution on the enrichment of helium rich natural gas reservoirs.The aim is to provide new ideas for the establishment and improvement of a helium resource investigation and evaluation system.The results show that:(1)The crustal-derived helium gas in the Weihe Basin mainly comes from helium source minerals rich in U and Th elements such as zircon,apatite,etc.,which are relatively scat⁃tered in rocks.The temperature range(>180℃)where natural gas is generated in large quantities and the main helium source minerals release helium gas has a high degree of overlap.(2)After the formation of the base⁃ment,the Weihe Basin underwent Paleozoic sedimentation and was subsequently strongly uplifted and eroded.A large number of Indosinian and Yanshanian granite bodies were formed on the surface,in which helium source minerals rich in uranium and thorium elements(mainly calcite,zircon,and apatite)continuously de⁃cayed to generate helium gas and partially enclosed the helium gas in the mineral lattic

关 键 词：渭河盆地 构造热演化 富氦天然气 氦气释放 富集成藏 

分 类 号：TE122.1[石油与天然气工程—油气勘探]