上海国土资源
上海國土資源
상해국토자원
SHANGHAI LAND&RESOURCES
2013年
4期
91-95,100
,共6页
岩石矿物学%岩矿测试%辉石闪长岩%锆石U-Pb定年%燕山晚期%岩浆作用期次
巖石礦物學%巖礦測試%輝石閃長巖%鋯石U-Pb定年%燕山晚期%巖漿作用期次
암석광물학%암광측시%휘석섬장암%고석U-Pb정년%연산만기%암장작용기차
petrological mineralogy%rock and mineral analysis%pyroxene diorite%U-Pb dating%late Yanshanian%magmatism times
齐贤桥辉石闪长岩体为一小型岩株，侵位于上侏罗统和寒武系之中。本文采用LA-ICP-MS方法开展了岩体锆石U-Pb定年，并讨论了其地质意义。定年结果表明，岩体形成于早晚白垩世之交，侵位年龄在99.5±1.2Ma~100.56±0.57Ma。结合区域地质资料和已有年龄，将区内燕山晚期的岩浆侵入作用划分为三次，分别约119.6~120.1Ma、98.3~112.7Ma和81~88.1Ma左右，以后两者为主。认为岩体为燕山晚期伸展拉伸构造体制下，主要受张堰-南汇断裂带控制被动侵位形成。燕山晚期以来，上海地区的岩浆作用年代与江山-绍兴断裂、温州-镇海断裂带带间的浙东南地区具有很大相似性，可能指示该阶段浙东南和上海地区构造体制的一致性。
齊賢橋輝石閃長巖體為一小型巖株，侵位于上侏囉統和寒武繫之中。本文採用LA-ICP-MS方法開展瞭巖體鋯石U-Pb定年，併討論瞭其地質意義。定年結果錶明，巖體形成于早晚白堊世之交，侵位年齡在99.5±1.2Ma~100.56±0.57Ma。結閤區域地質資料和已有年齡，將區內燕山晚期的巖漿侵入作用劃分為三次，分彆約119.6~120.1Ma、98.3~112.7Ma和81~88.1Ma左右，以後兩者為主。認為巖體為燕山晚期伸展拉伸構造體製下，主要受張堰-南彙斷裂帶控製被動侵位形成。燕山晚期以來，上海地區的巖漿作用年代與江山-紹興斷裂、溫州-鎮海斷裂帶帶間的浙東南地區具有很大相似性，可能指示該階段浙東南和上海地區構造體製的一緻性。
제현교휘석섬장암체위일소형암주，침위우상주라통화한무계지중。본문채용LA-ICP-MS방법개전료암체고석U-Pb정년，병토론료기지질의의。정년결과표명，암체형성우조만백성세지교，침위년령재99.5±1.2Ma~100.56±0.57Ma。결합구역지질자료화이유년령，장구내연산만기적암장침입작용화분위삼차，분별약119.6~120.1Ma、98.3~112.7Ma화81~88.1Ma좌우，이후량자위주。인위암체위연산만기신전랍신구조체제하，주요수장언-남회단렬대공제피동침위형성。연산만기이래，상해지구적암장작용년대여강산-소흥단렬、온주-진해단렬대대간적절동남지구구유흔대상사성，가능지시해계단절동남화상해지구구조체제적일치성。
The Qixianqiao pyroxene diorite pluton is a smal-scale stock, which was emplaced between the Cambrian and Upper Jurassic periods. In this study, the pluton was Zircon LA-ICP-MS U-Pb dated and its geological implications discussed. The dating results showed that the pluton was intruded during the transition between the Early and Late Cretaceous, at about 99.5±1.2 to 100.56±0.57 Ma. Combining this new dating evidence with the regional geological data, this paper concludes that the Late Yanshania magma was intruded during three phases, at approximately 119.6-120.1, 98.3-112.7, and 81-88.1 Ma, the later two phases being the main intrusive episodes. The pluton intruded passively and was control ed by the Zhangyan-Nanhui fault belts, during the late Yanshanian extension. From the Yanshanian, magmatism in the Shanghai area was similar to that in southeastern Zhejiang between the Jiangshan-Shaoxing and Wenzhou-Zhenhai fault belts, indicating that the tectonic systems in these areas may have been similar during this period.
