中国地质
中國地質
중국지질
CHINESE GEOLOGY
2010年
2期
488-494
,共7页
Rb-Sr同位素年龄%沉积改造型铅锌矿%跑马%扬子地台
Rb-Sr同位素年齡%沉積改造型鉛鋅礦%跑馬%颺子地檯
Rb-Sr동위소년령%침적개조형연자광%포마%양자지태
Rb-Sr isotopic age%reworked sedimentary stratoid (irregular) lead-zinc deposit%Paoma%Yangtze plate
四川省宁南县跑马铅锌矿床是产于下寒武统麦地坪段白云岩中的层控矿床,主要受层间破碎带控制,有两个含矿层.该矿床是沉积改造型铅锌矿床,Pb+Zn的品位6%～9%A.富矿可达30%以上.笔者利用TLMS测试技术获得闪锌矿的Rb-Sr同位素年龄值,结果表明跑马铅锌矿化等时线年龄为(200.1+4.0)Ma.属印支晚期-燕山早期.由于该矿床与云南会泽铅锌矿年龄相近,推断为同一构造-岩浆活动的产物.
四川省寧南縣跑馬鉛鋅礦床是產于下寒武統麥地坪段白雲巖中的層控礦床,主要受層間破碎帶控製,有兩箇含礦層.該礦床是沉積改造型鉛鋅礦床,Pb+Zn的品位6%～9%A.富礦可達30%以上.筆者利用TLMS測試技術穫得閃鋅礦的Rb-Sr同位素年齡值,結果錶明跑馬鉛鋅礦化等時線年齡為(200.1+4.0)Ma.屬印支晚期-燕山早期.由于該礦床與雲南會澤鉛鋅礦年齡相近,推斷為同一構造-巖漿活動的產物.
사천성저남현포마연자광상시산우하한무통맥지평단백운암중적층공광상,주요수층간파쇄대공제,유량개함광층.해광상시침적개조형연자광상,Pb+Zn적품위6%～9%A.부광가체30%이상.필자이용TLMS측시기술획득섬자광적Rb-Sr동위소년령치,결과표명포마연자광화등시선년령위(200.1+4.0)Ma.속인지만기-연산조기.유우해광상여운남회택연자광년령상근,추단위동일구조-암장활동적산물.
Located in Nanning County of Sichuan Province, the Paoma lead-zinc deposit is a stratabound deposit in a cataclastic zone of Lower Cambrian Maidiping dolomite. Being a reworked sedimentary srratoid (irregular) lead -zinc deposit, it includes two ore horizons. Pb and Zn in the ore deposit are economic elements possessing an average grade of 6%～9%, with the grade of rich ore in excess of 30%. The sphalerite Rb-Sr isochron age of 200±1 Ma by TIMS method suggests an age of Late Indosinian-Early Yanshanian. This ore deposit has the same age as the Huize lead-zinc deposit in Yunnan Province, and therefore it is inferred that they had the same ore-forming setting.
