吉林大学学报(地球科学版)
吉林大學學報(地毬科學版)
길림대학학보(지구과학판)
JOURNAL OF JILIN UNIVERSITY(EARTH SCIENCE EDITION)
2014年
2期
419-431
,共13页
王霄飞%李三忠%龚跃华%刘鑫%索艳慧%戴黎明%马云%张丙坤
王霄飛%李三忠%龔躍華%劉鑫%索豔慧%戴黎明%馬雲%張丙坤
왕소비%리삼충%공약화%류흠%색염혜%대려명%마운%장병곤
南海北部%活动构造%断裂%气底辟%地震%火山岩%天然气水合物
南海北部%活動構造%斷裂%氣底闢%地震%火山巖%天然氣水閤物
남해북부%활동구조%단렬%기저벽%지진%화산암%천연기수합물
northern South China Sea%active tectonics%faults%gas chimneys%earthquake%igneous rock%gas-hydrates
海底天然气水合物与活动构造关系极为密切,随着近十几年来海底天然气水合物勘探与研究取得的重要进展,相关活动构造也正在逐渐受到关注。通过对断裂、地震、气底辟以及海底火山活动等构造活动的多种表现形式的研究,分析了南海北部活动构造的特征。在南海北部,存在北东向、北东东东西向、北西向3组活动断裂,其中北西向断裂切割其他两组,形成最晚。这些活动断裂以继承性为主,北东向和北东东向断裂均为切割地壳或岩石圈的大断裂。南海北部的震中呈带状分布,在东部呈北东走向,而西部受红河走滑断裂的影响,震中整体为北西走向分布。气底辟是对天然气水合物形成有重要指示意义的构造,同断裂一样,气底辟为气源垂直向上移动至形成水合物的温压带提供了良好的通道。南海北部分布的火山岩由东到西顺时针旋转。从地震剖面可以看出,岩体明显受张性断裂控制。东部天然气水合物的分布受北西向活动断层的影响较大,而西部则与海底滑坡密不可分。
海底天然氣水閤物與活動構造關繫極為密切,隨著近十幾年來海底天然氣水閤物勘探與研究取得的重要進展,相關活動構造也正在逐漸受到關註。通過對斷裂、地震、氣底闢以及海底火山活動等構造活動的多種錶現形式的研究,分析瞭南海北部活動構造的特徵。在南海北部,存在北東嚮、北東東東西嚮、北西嚮3組活動斷裂,其中北西嚮斷裂切割其他兩組,形成最晚。這些活動斷裂以繼承性為主,北東嚮和北東東嚮斷裂均為切割地殼或巖石圈的大斷裂。南海北部的震中呈帶狀分佈,在東部呈北東走嚮,而西部受紅河走滑斷裂的影響,震中整體為北西走嚮分佈。氣底闢是對天然氣水閤物形成有重要指示意義的構造,同斷裂一樣,氣底闢為氣源垂直嚮上移動至形成水閤物的溫壓帶提供瞭良好的通道。南海北部分佈的火山巖由東到西順時針鏇轉。從地震剖麵可以看齣,巖體明顯受張性斷裂控製。東部天然氣水閤物的分佈受北西嚮活動斷層的影響較大,而西部則與海底滑坡密不可分。
해저천연기수합물여활동구조관계겁위밀절,수착근십궤년래해저천연기수합물감탐여연구취득적중요진전,상관활동구조야정재축점수도관주。통과대단렬、지진、기저벽이급해저화산활동등구조활동적다충표현형식적연구,분석료남해북부활동구조적특정。재남해북부,존재북동향、북동동동서향、북서향3조활동단렬,기중북서향단렬절할기타량조,형성최만。저사활동단렬이계승성위주,북동향화북동동향단렬균위절할지각혹암석권적대단렬。남해북부적진중정대상분포,재동부정북동주향,이서부수홍하주활단렬적영향,진중정체위북서주향분포。기저벽시대천연기수합물형성유중요지시의의적구조,동단렬일양,기저벽위기원수직향상이동지형성수합물적온압대제공료량호적통도。남해북부분포적화산암유동도서순시침선전。종지진부면가이간출,암체명현수장성단렬공제。동부천연기수합물적분포수북서향활동단층적영향교대,이서부칙여해저활파밀불가분。
Submarine gas hydrates are closely related to active tectonics.Recently submarine active tectonics in the northern South China Sea attract much attention because of exploration of submarine gashydrate in the past decades.We descript the features of faults,earthquakes,and volcanic activity and other active tectonics relating to gashydrate.There are three sets of active faults including NE-,NEE-EW-,NW-striking faults in the northern South China Sea,of which NW-trending faults cut the other two groups.Most of these active faults are inherited from pre-existing basement faults.NE-and ENE-trending faults are crustal or lithospheric faults.The earthquake distribution is focused on a NE-trending striped region of the northern South China Sea.However,the NW-trending earthquakes are controlled by the Red River strike-slipping fault.Gas chimneys are related to active structures that play an important role of the formation of the gashydrates,as same as the channel which provides the gas to vertically migrate up to the place under appropriate temperature and pressure for gas-hydrate formation. The distribution of volcanic rocks clockwise rotates from east to west.Based on seismic profile,the volcanic rocks are controlled by tensional fault.The distribution of gashydrates in the eastern part is affected by the NW-trending active faults,however,the west is inextricably linked with the submarine landslide.