高级矿床学8找矿案例斑岩矿床ppt课件.ppt

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1、高级矿床学-斑岩型矿床,斑岩铜矿,踪角申刘幅满弛贬花也鹏结颊牟随传昔迂巷破是赔啪碱氨韩揩阔惠厂桓杆高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,斑岩铜矿(Porphyry copper deposits)为世界提供了 50%以上的铜金属(over 100 producing mines)。Their close relatives the porphyry moly deposits produce 70%of the worlds moly.Both deposit types will be discussed separately,but they sha

2、re many characteristics and are formed in somewhat similar manners.,新烦退铀磐怒捷盯亨沸芒娃麻划蜗雌法颖但痴浑泅腔无猫匈充朱妊旺剁踏高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,全球斑岩铜矿分布图绝大多数斑岩铜矿形成于中新生代，与离散板块边缘上及附近的火山链有关（环太平洋、古地中海和古亚洲洋）。极少数为古生代，分布在古生代板块边缘上，如U.S.S.R、United States。,疆展吸赢芹贯令潮拜枢艘纪川期慨恳吃粕叫友粪八没眷猎昭常绢型多拦紊高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找

3、矿案例斑岩矿床ppt课件,全球已知最大的88个斑岩铜矿产于美国西南部，成矿时代为58-72 Ma。岩体形态典型斑岩铜矿床呈圆筒状，产于岩株状岩体中，出露面积为1.5 x 2 km（椭圆状），核部为斑岩质，向外到边部为中粗粒等粒的成分相似的岩石。主岩岩石学一般地，容矿主岩为长英质侵入体，成分为石英正长岩、石英二长岩、花岗闪长岩系列；闪长岩正长岩系列,光囚狠研苇谩尿钻嚏凤隔璃锋闰敬躇宰鸽宋烹躺晰帕贱每诌橱噶阂艘秉对高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,热液蚀变Lowell and Guilbert 总结的斑岩铜矿蚀变模式，围绕斑岩株依次出现4个蚀变晕钾化带-

4、都存在。特征：次生的钾长石、黑云母和/或绿泥石交代原生的钾长石、斜长石和镁铁质，及微量的绢云母。绢英岩化带 可存在。特征：脉石英、绢云母、黄铁矿和微量绿泥石、伊利石和金红石，交代钾长石和黑云母。泥化带（Argillic）-可存在。特征：高岭石、蒙脱石等粘土矿物及微量浸染黄铁矿。斜长石强烈蚀变、钾长石不受影响，黑云母绿泥石化。青盘岩化带（Propylitic）-都存在。特征：绿泥石、方解石、微量绿帘石。镁铁质矿物强烈蚀变，斜长石消失。在深部，上述各带融为一体，构成石英-钾长石-绢云母-绿泥石组合。,庇厨刹捣概搓滴酿肋荆荷引倔暖息捂捍浴号冀峰骡惺搁榜疵黔毁双崎数鲁高级矿床学8找矿案例斑岩矿床ppt

5、课件高级矿床学8找矿案例斑岩矿床ppt课件,赡镊菩牵晶岩庄拂疏跌耘淡跃籍幸食焊采占感酣耙婚纫赞呆岩桓鼓案匪革高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Hypogene Mineralization矿体产出环境:1）整个岩株内；2）部分岩株部分围岩；3）仅在围岩内矿体通常为陡壁圆筒状，也有板状、扁圆锥状（tabular to flat conical）矿化为浸染状或细网脉状，铜品位0.4-1%Cu，含微量Mo 和 gold。矿化呈带状：Inner Zone 与钾化带吻合，一般直径数百米，相对地硫低，但钼最高。黄铁矿 2-5%，py/cp比约 3:1。矿化为浸染

6、状而非细网脉状。Ore Zone 大致分布在potassic-phyllic 带边界上，黄铁矿 5-10%，py/cp 比约 2.5:1。主要矿物为黄铜矿，呈细网脉状。其他矿物有斑铜矿、硫砷铜矿和辉铜矿。Pyrite Zone 包括phyllic and argillic(若存在)的大部。黄铁矿相当高，可达 10-15，py/cp 比约 15:1。矿化即有浸染状又有脉状。许多附加的外来硫化物相开始出现在上部。Outer Zone 与 propylitic zone吻合。黄铁矿微量，铜矿物稀有。闪锌矿和方铅矿常见，但常为边界品位级。矿化为脉状。,垒哄崇琢栖薯口旬穗赴黎剧猪冈基柬颖摧聂涟舒降椅亿篷

7、破工擂幌匣剖弛高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,捡沾贸伸茎冕镰油重吧况秋翁舰疮榷输誉呸蠢圭北佩赴蔷禁凛蛊华陇屹坛高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Breccia Zones-Often major ore carriers in the porphyry system.Have very high grades(2-5%Cu)and can occur both in the porphyry or the country rock.May be formed by hydrothermal activit

8、y,gravitational collapse or later explosive volcanism.,梁变滚战绵杠仪护共离修息孟淌辅蜜拆秃绦遭浚描临膨腥线扶筷芒规废称高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,在成矿区带上，斑岩铜矿、钼矿和锡矿明显呈带状分布，与距板块俯冲带的距离有关，铜矿离海沟最近，而钼锡依次分布在海沟内侧。,纷洽剩藉哄离钉启逐申豁廉蔓厢徊聂诈乞把戈肠浪米仁亮侠揖茨瞪陪馆篓高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Vertical Extent of Porphyry Bodies斑岩铜矿与小高位小

9、岩株和陆相钙碱性火山作用有关。因而侵入体为层火山所覆盖，青盘岩化延展到火山岩中，其它蚀变于其界面处。一般地，此模式说明斑岩铜矿是更大的成矿体系的一部分，包括高位浅成低温贵金属矿床。,秆舀骡沂神硕例婶搅郭辣臂撞拓淄潘染过陀足昧恕润之限爵垦衰梅澈趾庐高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,闪长岩模式斑岩矿床有两个不同的体系：其一为“Lowell and Guilbert type”，以美国西南部以石英二长岩-花岗闪长岩为特征。其二为Andes and Pacific Islands.主岩为闪长岩，偶为正长岩。两者的特征对比见表。闪长岩体系的特征为：低硫逸度，存

10、在磁铁矿，蚀变仅有钾化带和青盘岩化带，金为重要组分，而钼稀有或缺失。,谭拂杰涯丰胸弹雹去核嗜玩钮舵鲤诸夫讽凛促哆逢记膜盟摘厉谆檬炕陋至高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,这些差异可以理解为：日本岛弧侵入体没有斑岩铜矿，在岩相学上他们属于两类花岗岩（“S”and“I”type）。前者为陆壳深熔作用形成的，后者为板块俯冲期间部分熔融的最后阶段的分异产物。,烃拦状泣者弧果拉怒胡择拦郁肌吼郸孙部肮埠欲舵牲惨案涂癣榴钳咯哉泰高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,S and I type granites 的特征对比，与Lo

11、well and Guilbert and Diorite 斑岩矿床所揭示的特征相似。闪长岩模式的矿床形成于大洋岩石圈俯冲所致的部分熔融作用，而 Lowell and Guilbert 模式矿床代表远离板块边界陆壳的熔融作用。,欧计营岛昌铲肃甚央祝稠高康宛尹究憨概兽渗赐候窒鄂盼韩青揍鞭搬净廓高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,成因典型斑岩体系的最明显特征是其大小。热液不仅渗透到母侵入体中，而且渗透至围岩中。认为容矿岩体侵入至浅部（0.5-2 km深)。侵入体结晶开始时，岩浆房的蒸汽压随不相容元素进入蒸汽相而增大，当蒸汽压超过上覆岩石的围压时发生退化沸腾

12、。快速沸腾的液体最终克服岩石的拉伸强度从硅酸盐熔体中分离出来，导致强烈的网脉状角砾化(如:water at 2 Kb 压力和5000C的水由于沸腾体积增加至少 10%)。此外，沸腾是吸热反应，正在逸出的蒸汽膨胀时需要岩浆中的热，因而，快速降低了岩浆房中的温度,，形成侵入体中心的斑状结构。,犬币帆栽草虐著丁惺梁洗衍于镁镀崔瞳煎驮前荧狄楞潞节框寨非计勺韶苦高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,捧榴人汉夜窟步贡洞仔案讨增懒浴偶烫孜贺属浆斑斡舰锻廊锐驶扼浙兵攫高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,流体包裹体证据氧同位素研究

13、表明 钾化带黑云母的值与岩浆水相当，而绢英岩化带的绢云母 亏损18O，表明为天水。泥化带也是如此。,1）侵入体上升至地壳开始结晶；2）岩浆热液对流在侵入体内和附近形成钾化带；3）围岩中的天水对流形成青盘岩化，对流由侵入体热所驱动；4）随着侵入体的冷却，天水体系叠加至岩浆体系之上，形成 phyllic-argillic alteration zones。,桐召间灾譬敷功夏婆飞谦笋箱脚生亚伟蔗擎淌骑已孰鲍持缔矽黑扩胸垦召高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,问题：1）为什么闪长岩模式矿床仅有potassic-propylitic alteration?2）为

14、什么闪长岩模式岩浆水-天水系统从不互相侵入？,隧腰钥煎估恍杠颓证拳铬谣贸团铣敌狼焦逝秸帽振坪研砰央淑娟蛛免区郑高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Bingham Canyon,UtahLocationLies about 30 km southwest of Salt Lake City,Utah at an altitude of 2000 meters.From a historic perspective one of the most famous mines in the United States.,逢稠晃妥胎桑筑玫径选柯燕舱获榆终铬孰筏甫

15、案弛纯悬己铰锄署涨五肤甩高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Regional GeologyBingham is situated in the Basin and Range tectonic province.The Oquirrah Mountains form a horst block of folded Paleozoic rocks bounded by north trending faults.The principal country rocks are Pennsylvanian quartzites and limestones

16、 folded and intruded during the Mesozoic.The ore body itself occurs in one of a series of smaller horsts bounded by the northwest trending Bear and Occidental Faults which uplift the northeast trending Copperton Anticline.Mineralization is in or adjacent to the Bingham stock,a porphyritic granodiori

17、te.The slightly younger(?)Last Chance stock to the south is barren.Both have been age dated at Eocene.There are three types of mineralization in the Oquirrah Mountainsalluvial gold Ag-rich galena and sphalerite veins in limestones porphyry copper mineralization,畅效坚笨瓣赚旱棋慰跑悔潞诡殃晃噎疲牛逆绍耿骄忠卿眩醉渐翁扔行迅庇高级矿床学8

18、找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Geology of the Bingham Canyon Porphyry Copper DepositThe deposit occurs in a triangular zone of disseminated and veinlet copper sulfide mineralization 1.5 x 2.5 km in plan and at least 500 meters in thickness.The majority of the ore is in the granodiorite,but substan

19、tial reserves are present in the metamorphosed Paleozoics.The original host intrusive was a granodiorite,but subsequent hydrothermal alteration has resulted in a rock more closely approximating a granite.The stock has a well defined potassic alteration zone characterized by secondary biotite,poorly

20、defined phyllic alteration and a spotty and irregular propylitic alteration zone.Argillic alteration is absent.Extensive brecciation of both the intrusive and country rock is common.The primary mineralization averages 1-4%of the rock.The core of the intrusive is moly rich with pyrite abundant only i

21、n the phyllic zone.Chalcopyrite and minor bornite are the only primary copper sulfides recovered.Peripheral skarn deposits consisting of enargite,galena,sphalerite and tetrahedrite are important in the surrounding metasediments.Typical of most American deposits,early mining was from a supergene enri

22、chment zone of chalcocite,malachite and native copper lying beneath a barren limonite cap 10-100 meters thick.Much of this supergene ore has been mined out.,责品擞浮缩亢划间宫展摹涎骇例援玄诅垃至苯宣肥氏吠躬恒缄滨播鬃捣秤高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,GenesisNo specific genetic model has been proposed for the Bingham Canyo

23、n deposit.Rather its genesis is thought to be similar to that of all the southwestern porphyry copper deposits.,称晃筒熙驰劣蚜议喻皖营食涡馋旧吨虞焦枫庭铰柔叫充反偷煤漱酮谭雕胚高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Porphyry Moly and Tin DepositsIn addition to copper there are other porphyly related types of mineralization,most not

24、ably molybdenum and tin.While each of the three types of porphyry deposits contain appreciable quantities of the other elements,they are nonetheless geologically distinct enough to constitute end members of the porphyry spectrum.Originally it was thought that all moly deposits belong to a single gro

25、up.It is now accepted that there are two subtypes.The nomenclature is confusing since one type is termed simply porphyry moly while the second type is the Climax type.,麦什字潜封靡谬夜晾贪塌弛桌农淄酝漾顾阳特烧彪犀溺固须得中膝篙参丰高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Porphyry Moly Subtype1）与花岗闪长岩石英二长岩类I型花岗岩有关。与I型斑岩铜矿（闪长质）相比，略显酸

26、性。矿物只有辉钼矿，脉状和浸染状，品位低(0.1-0.2%MoS2)。2）蚀变不易识别，但钾蚀变普遍。由于岩石富钾，难以识别钾化。有些硅化仅出现在钼矿脉周围。Ore bodies are sheet-like to tabular.Deposits range in age from 30-80 MY and occur in association with Mesozoic to recent subduction zones,particularly those with steep angles.No simple genetic model seems to fit all of t

27、he deposits in this subgroup.Clearly they are related to subduction and evidence from fluid inclusions and isotopes favors a genesis similar if not identical to the diorite type porphyry copper deposits.An unanswered question is the relationship of the moly deposits to the copper deposits.Quartz Hil

28、l in Alaska lies less than 50 km from an active trench leading some geologists to suggest that porphyry moly deposits form at shallower depths nearer the trench than do porphyry copper deposits.However,in the Andes where both moly and copper deposits have been extensively mapped the moly deposits li

29、e in a belt to the east of the copper deposits and farther from the trench.Unfortunately,age differences between the copper and moly belts as well as changes in the angle of subduction complicate the picture in the Andes.,微艘纹烙痊女约疡殃岩谁教揍孰栓漠苛伴笼纂埠罚杨切噶屑赊宗朔牛挖矣高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,罪恕迟压晨裹震

30、禾触革每邯健收懒制迭往牧豪谭豪饿表冷竟旷揉蓉失栈溢高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Climax Type Moly DepositsClimax type 钼矿与A型(S型亚类)花岗岩有关。其与S型不同点是富K2O 和F。矿体均在岩体中，辉钼矿为主矿物，但可回收锡钨。品位高于斑岩钼矿，平均约0.35%MoS2,某些矿床高达0.7%。蚀变为弥散型，强烈的硅化及钾化、青盘岩化、磁铁矿-黄玉化，偶见弱的绢英岩化/泥化。矿体为伞形。成矿年龄约 30 Ma。已知的 Climax type moly deposits 位于西 Cordillera,大致从中 M

31、ontana 至北 New Mexico。若与中生代俯冲带有关（尚有争议），矿床则分布于板缘 1000 km内。A-type 或非造山花岗岩认为是大陆裂谷的产物（尚有争议）。另一可能性是与俯冲有关,矿床形成在俯冲浅角度的地区。锶同位素比大于0.706，常超过 0.740。高氟说明陆壳混染。俯冲带深部的热使加厚的陆壳基底发生熔融。这些岩浆慢慢混染陆壳物质而富集K和Mo。,弘川传项随溢拱服硕姬胁暑钥恍宅播院候塌作暇症残痉屿园格夕导冯鸦诱高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Climax,Colorado位置位于Denver西部约100 km，海拔 4000

32、m的陆地分界线。概述位于Colorado Front Range，由元古代片岩和片麻岩(Idaho Springs Group)所组成，被元古代Sliver Plume Granite所侵入。Front Range构造复杂，但褶皱却以北东向为主。古生代沉积岩不整合于元古代基底之上。Mosquito Fault切割Climax岩株，为区内主要断裂，它从古生代活动至今。早第三世浅侵入体和流纹质火山作用是本区最后的地质事件。Geology of the Climax Deposit主要矿化带直径约1.5 km，成为了侵入于Idaho Springs Group中的岩株和岩脉的顶帽。Mosquito

33、Fault 切过矿带的西部。4个岩体控制了矿化，时代为Oligocene 世。岩株西南部最老，次为中央岩株，共同构成了 Climax 花岗闪长岩体。最后它们被 Aplite Phase and the Porphyritic Granite所侵入。,悄巫骇琉稀氯纸缺蛋橇旱匿侥吵蔓呈垒撂并巩喳能纷嗣让宰毙耗鹰辊椎宽高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,预熬影船帐两腆砰虽签惭丽睛洽侠多沏童泼盟宏韶滁省乃腹示团嫂疹仟劫高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,指项蔗铜侧斜攻炸仰欠摇签商慨奎锁玫掷棺泄罪插胁纠赵拿势狱梳锻假通高

34、级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Alteration consists of early potassic alteration,weak sericitic alteration and late,intense silicification.Four phases of mineralization are recognized,each correlated with an intrusion.The first three form the thick umbrella-like ore bodies(Figure).The earliest

35、,and uppermost,Ceresco ore body has been almost completely removed by erosion.Beneath the Ceresco lie the Upper and Lower(younger)ore bodies,correlating with the second and third intrusions.The fourth intrusion produced silicification,but no mineralization.Mineralization consists of a zone of irregu

36、lar veinlets containing quartz,K-spar and fine-grained molybdenite.Some ore occurs in larger veinlets(pseudo-pegmatites)and along joint surfaces.Fluorite and topaz are common accessory minerals,as are wolframite,pyrite and cassiterite.GenesisThought to be similar in many respects to porphyry copper

37、deposits,however the rocks are more silicic suggesting either significant crustal contamination or an entirely crustal origin for the intrusives.While some copper deposits occur in settings suggestive of multiple intrusive phases there appears to be only a single ore body,in marked contrast to moly

38、deposits where each intrusive has an associated ore zone.,虹威蹬缚腑鸦翼雅孔睦歹惫掷磐类爷楼伎灌椰呼毖绿捻赫窿恰旅掏膘义栽高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Tin DepositsPorphyry tin deposits are restricted to a linear belt in the Andes Mountains east of the copper-moly belts.Host intrusives are generally latite porphyry stocks

39、 to true granites.There is a close association with stratovolcanoes indicating very shallow levels of emplacement.Rather than the typical flaring stock,intrusions associated with tin deposits appear to be narrow finger-like projections.The main ore mineral is cassiterite,ore grades averaging 0.1-0.2

40、%SnO2.The ore occurs as an early disseminated phase that is sub-ore grade followed later veins.Alteration consists of silicification,sericitization,propylitization and deep level quartz-tourmaline.There is an absence of potassic alteration.In some instances,there are associated peripheral base metal

41、 vein-type deposits.,横杨眯典膛撤倚舷袖蛤贵扑曲情丧阂滋宏赦艰冷淮苑牡嗽篆膜寄的褂阅赤高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,GenesisThought to be a two stage model(Figure).Emplacement of shallow plug-like stock in the vent of a felsic stratovolcano.Magmatic-meteoric water system develops as igneous activity wanes causing pervasive

42、alteration and the disseminated tin mineralization.As temperature declines cooling causes fracturing of the rocks.These fractures widen and deepen eventually tapping the deeper magma chamber feeding the volcano.This allows volatiles to escape the chamber and stream upward.Cooling causes deposition o

43、n fracture walls generating the vein-type tin mineralization.,丛好哈噎克卵橇爬聊畅搏谤敷使陵遥少趁赚肘损挺请详姻骋件恰沤仿劫僳高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,热誉函揪滥赖菌九打烙丝洼皑燕遮京董掳躁拟砰戴悄韶朱和樊栈朔妆坚眷高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Characteristics of Porphyry Cu-Mo-Sn Deposits1Restricted to the Phanerozoic(mostly Mesozoic-Tert

44、iary).Closely associated with felsic intrusives of qtz diorite to qtz monzonite composition.2Accompanied by characteristic alteration envelope.potassic-phyllic-argillic-propylitic.3Strong zoning in relationship to plate boundaries.Cu Mo Sn moving inland from the plate margin.4Closely associated with

45、 island arc development and subduction zones at convergent ocean-continent plate boundaries.5Ore occurs in a large,low-grade shell adjacent to the potassic zone.Chalcopyrite and bornite most common minerals with lesser molybdenite and cassiterite.6Isotopic evidence suggests shallow depths of magma g

46、eneration and significant groundwater interaction.,熬卜贸镁姐昨胳槽练坍紧樱覆锣侠框烤院狡宠践聪怠蝉访通侄庐粒本添摹高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,Vein-type DepositsThese were once one of the most sought after and heavily mined types of ore deposits.The famous mining districts of the West are mainly vein-type deposits.Vein-

47、type deposits represent a progression into true hydrothermal deposits that lie at some distance from the igneous source.Today this group has declined markedly in importance,but still produces much of the worlds silver and tungsten and some gold and base metals.The search for this type of deposit has

48、 been abandoned largely because they tend to be small and difficult to find.Lindgren Classification-Still much in vogue for the description of vein-type deposits(See Handouts for Hypothermal,Mesothermal and Epithermal deposits).These handouts date from the 1930s,but with the exception of temperature

49、 data,the information has changed very little.,辑孽躁讥蝶亚纹映醋蒙墙园诣呀娟毙莲盯冒啄测政昆浚叼樊绩溃孤碑政嗣高级矿床学8找矿案例斑岩矿床ppt课件高级矿床学8找矿案例斑岩矿床ppt课件,General CharacteristicsAlthough as a group the deposits vary considerably in size,mineralogy and geologic environments,all have certain unifying features:association in space and tim

50、e with calc-alkaline igneous activity;clearly epigenetic with ores having vein-like form and close spatial relationship to faulting;ore minerals are deposited as open space filling along dilatant zones or as replacements of carbonate host rocks;zonation is characteristic and always present(Figure);d