CAJ | 학술논문

庐枞盆地是长江中下游成矿带中的重要铁（铜）矿集区，盆地内闪长玢岩与成矿作用关系密切，但目前对庐枞盆地内闪长玢岩地球化学特征及形成时代的认识仍存在争议。本文分析了庐枞盆地内闪长玢岩的主量元素、微量元素、Sr-Nd-Pb同位素组成特征，并利用LA-ICP MS对盆地内泥河铁矿及汪庄铜矿深部的闪长玢岩样品进行了锆石U-Pb 定年。泥河铁矿深部两块闪长玢岩样品中锆石的206 Pb/238 U 加权平均年龄分别为138±1．4Ma及134．5±1．8Ma，而汪庄铜矿三块样品锆石 U-Pb 定年结果分别为133．9±1．9Ma、137．5±1．6Ma 及135．8±2．2Ma。研究结果显示庐枞盆地内闪长质岩浆活动的开始于138 Ma 左右，并可能一直持续到约134Ma。而庐枞盆地内这期较早的岩浆活动可能与周边隆起区（铜陵）约140～145Ma的岩浆活动类似，同时与区内早白垩世成矿作用密切相关，对于在庐枞盆地开展深部找矿具有重要的指示意义。
려종분지시장강중하유성광대중적중요철（동）광집구，분지내섬장분암여성광작용관계밀절，단목전대려종분지내섬장분암지구화학특정급형성시대적인식잉존재쟁의。본문분석료려종분지내섬장분암적주량원소、미량원소、Sr-Nd-Pb동위소조성특정，병이용LA-ICP MS대분지내니하철광급왕장동광심부적섬장분암양품진행료고석U-Pb 정년。니하철광심부량괴섬장분암양품중고석적206 Pb/238 U 가권평균년령분별위138±1．4Ma급134．5±1．8Ma，이왕장동광삼괴양품고석 U-Pb 정년결과분별위133．9±1．9Ma、137．5±1．6Ma 급135．8±2．2Ma。연구결과현시려종분지내섬장질암장활동적개시우138 Ma 좌우，병가능일직지속도약134Ma。이려종분지내저기교조적암장활동가능여주변륭기구（동릉）약140～145Ma적암장활동유사，동시여구내조백성세성광작용밀절상관，대우재려종분지개전심부조광구유중요적지시의의。
Luzong basin is one of most important units of the iron-copper-polymetallic mineralization belt in the Middle-Lower Reaches of theYangtze-River Area.In Luzong basin,diorite-porphyrite is closely related to ore-forming,but its geochemical characteristics and formation age is still controversial.In this paper, based on the study of major elements and trace elements and Sr-Nd-Pb isotopes,five diorite-porphyrite samples were selected for zircon U-Pb dating.Zircons of two samples from Wangzhuang copper deposit yielded weighted mean 206Pb/238 Uages of 138 ±1. 4Ma and 134. 5 ±1. 8Ma,respectively;while zircons from three samples from Nihe iron deposit yielded weighted mean206Pb/238Uages of 133. 9±1. 9Ma、137. 5 ±1. 6Ma and 135. 8 ± 2. 2Ma respectively.Therefore,there may be a early magmasim inLuzong basin similar to the magmasim with the ages of 140~145 Ma in the peripheral uplift area(Tonglin).However, this stage of magmasim continued to ca.134Ma in Luzong basin,it is closely related to the metallogenic activity during early Cretaceous and has important significance on deep ore searching.