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老挝班康姆金矿床存在两类金矿化,即产于安山岩与大理岩接触带处并受断裂带控制的低温热液硫化物原生金矿化和产于原生金矿化附近的残坡积红土型金矿化。红土型金矿化主要呈带状或似层状产出于第四系红土层中。研究认为,本区红土型金矿化主要为原生金矿受物理风化作用而形成的残坡积再生改造型金矿,成矿过程主要受原生金矿化及红土化作用控制,并结合地质、化探特征在本区圈出7处找矿靶区。 相似文献
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永顺县石英型砂,是一种具有“圆、纯、光”等特点的优质天然硅砂,属于特级品的铸钢用树脂砂类型。矿床赋存在第四系底部,直接底板为寒武系陆屑云岩或陆屑灰岩。矿体呈大透镜状或似层状。矿床成因属第四纪残积型。在区域上,砂矿体分布严格受寒武系地层、第四纪地貌以及中低纬度的亚热带气候控制。 相似文献
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菲律宾迪纳加特岛汇洋镍铬矿区发育板块碰撞成因的蛇绿岩,主要岩性为纯橄岩和方辉橄榄岩,与铬铁矿化关系密切,在纯橄岩和方辉橄榄岩的过渡带中铬铁矿化较为集中,铬铁矿多呈薄层块状或浸染状与围岩岩性条带呈"互层状"产出,块状、浸染状的铬铁矿重复出现;矿区内原生铬铁矿化非常普遍,虽然未构成原生铬铁矿体,但为次生红土型铬铁矿的成矿提供了丰富的物质来源。矿区内第四系中赋存有残坡积红土型铬铁砂矿,并与同类型镍矿共生;铁质红土层是最佳的含矿层位,松散状红土层次之;铬铁矿体呈层状、似层状,有3个铬铁砂矿化区,矿体厚度5~7m,铬铁矿品位w(Cr2O3)=2.0%~4.1%。 相似文献
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《矿物岩石》2017,(4)
白泥山磷矿位于晚震旦世禄劝--晋宁潮坪聚磷带中段、安宁-华宁-曲靖成磷区西缘,是近几年新发现、勘查的中型风化淋滤残积型磷矿床,与下寒武统海相沉积型磷块岩矿床关系密切但又相对独立,具有残坡积和淋滤次生双重特点。磷矿体呈面形似层状赋存于第四系残坡积层的混杂层中。矿体南北长约4 000m,东西宽200m~2 500m,垂厚1.10 m~72.79 m,平均12.99 m,厚度变化极不稳定;w(P_2O_5)为15.23%~38.941%,平均23.21%,伴生有用组分F含量较高,平均w(F)2.13%;矿体品位与第四系全层、混杂层、矿层厚度的相关系数分别为-0.089,-0.061,0.345,之间相关性不明显;R_2O_3及SiO_2含量较高,CaO,MgO,CO_2含量较低,体现了风化型矿石的特点。矿石自然类型主要为角砾状和砂土状矿石;Ⅰ品级矿石工业类型以混合型为主,Ⅱ品级及以下主要为硅质及硅酸盐岩型。磷矿体产状较平缓,埋深0~47.80m,矿石总体较疏松或半疏松,适宜露天机械化规模开采。除少量Ⅰ品级矿石能达到加工级,绝大部分矿石需经选矿除杂和提升品位,擦洗-脱泥-浮选工艺流程是目前较适合的成熟工艺,其尾泥处理和回收利用是技术要点和难点。 相似文献
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为适应生态地质调查和评价工作对成土母质研究的要求,以四川大凉山区为例,提出基于地质建造的成土母质分类方案,即以地质构造演化和地质建造环境为依据,结合残坡积物的成因类型对成土母质进行分类。大凉山区的成土母质可划分为第四纪冲洪积物、新近纪—第四纪砂泥岩类残坡积物、侏罗纪—白垩纪泥质岩类残坡积物、三叠纪砂泥岩类残坡积物、中生代中酸性岩类残坡积物、二叠纪基性—超基性岩类残坡积物、震旦纪—三叠纪砂泥岩类残坡积物、震旦纪—三叠纪碳酸盐岩类残坡积物、元古宙中酸性岩类残坡积物、元古宙火山碎屑岩类残坡积物、元古宙基性—超基性岩类残坡积物、元古宙变质岩类残坡积物等12类。研究表明,大凉山区成土母质和土壤存在差异性,但同一成土母质上的不同土壤类型具有一定相似的地球化学特征,不同成土母质形成的同一种土壤类型存在较大的地球化学差异。因此,基于地质建造的成土母质分类方案既能有效反映不同构造背景和成岩环境下的成土母质差异,又能有效表征成土母质与其上土壤的内在联系。 相似文献
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Debris flow deposits are the principal component of Quaternary continental slope sediments between the north-east Newfoundland Shelf and central Orphan Basin. In seismic profiles, these deposits occur as shingled, elongate, acoustically transparent lenses with their long axes orientated downslope. Deposits of individual flows form positive mounds on the sea floor; subsequent flows were diverted by the pre-existing topography into bathymetric lows between older debris flow deposits. These deposits show a large variation in the area of sea floor covered by individual flows (about 60–1000 km2), average thickness of deposits (9–37 m) and volume of sediment displaced (1–27 km3). The ratio of average thickness to a measure of deposit diameter, termed the aspect ratio, has a threefold variation from 0·0006 to 0·0021. Very low depositional slopes and low aspect ratios suggest relatively low viscosities, probably due to inmixing of water during downslope transport. Stratified sediments form three distinct horizons and are locally interbedded with the debris flow deposits. These are mainly hemipelagic deposits. The slope and rise to the west of the Orphan Basin are constructional in character. The apparent absence of upper slope erosional features and the abundance of debris flow deposits on the slope suggest that the supply of sediment to the continental slope occurred predominantly during times of maximum extent of Quaternary glacial ice. The ice sheet grounding line during several glacial maxima must have been situated at or near the present shelf break, supplying vast amounts of sediment directly to the upper slope. Oversteepening and subsequent slope failures fed material into deeper water. 相似文献
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Abstract. The Mutnovskoe deposit located in the Porozhisto‐Asachinskaya metallogenic province of South Kamchatka, Russia, is a polymetallic vein and Au‐Ag quartz vein associated type of hydrothermal deposit. The Mutnovskoe deposit is located inside a paleo‐caldera structure at the center of the Mutnovsko‐Asachinskaya geothermal field of Pliocene ‐ Quaternary age, where active gold deposition is identified in hot spring precipitate. The Mutnovskoe deposit is subdivided into the north flank, the central flank and the south flank based on the vein distributions and mineral parageneses. The mineralized vein system is oriented N‐S hosted in diorite ‐ gabbroic diorite stock, volcanic rocks and sedimentary rocks of Miocene ‐ Pleistocene age. The mineralization stage I (polymetallic vein) mainly in the central and the south flanks is Zn‐Pb‐Cu‐Au‐Ag contained in sphalerite, galena and tetrahedrite‐tennantite group mineral. The stage II (Au‐Ag quartz vein) occurs in the north and the central flanks. The stage III (Mn‐sulfide and Mn‐Ca‐carbonate vein) occurs in the whole deposit area. Stage II is the typical Au‐Ag quartz‐adularia vein of low‐sulfidation type. Stage III is alabandite‐rhodochrosite‐quartz‐calcite vein. The K‐Ar ages are 1.3±0.1 Ma for stage I sericite in alteration zone, and 0.7±0.1 Ma for the stage II adularia in mineralized vein. Based on the fluid inclusion study, range of ore forming temperature of the Mutnovskoe deposit is 200 to 260d?C (av. 230d?C). Salinities of fluid inclusions indicate 2.2 to 5.7 wt% NaCl in sphalerite and 0.8 to 3.3 wt% NaCl in quartz for the stage I. Mineral paragenesis of the polymetallic vein (stage I) is characterized by a district zoning of tennantite and Cd‐rich sphalerite in the south flank and tetrahedrite and Mn‐rich sphalerite in the central flank, which is due to the fractional crystallizations of ore‐forming fluid. Depositional condition of the low sulfidation state is inferred for the Mutnovskoe deposit, where the polymetallic vein of the south flank is in relatively higher sulfidation state than the central flank. 相似文献
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梭落底地区碳酸锰矿是云南省砚山地区近年来新发现产于中三叠统法郎组碎屑岩中的重要碳酸锰矿,在滇东南具有代表性.该类锰矿以矿层厚度大,出现多层而且相互平行产出为特征,与相邻的斗南、老乌锰矿进行对比,该碳酸锰矿沉积的氧化—还原界面深度比斗南、老乌锰矿更深,该类锰矿的形成很大程度上受下伏地层个旧组碳酸盐岩基底古地理的控制. 相似文献
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本文以航空γ能谱测量资料为依据,简述了与找钾有关的部分科研成果,建立了第四纪盐湖型钾盐矿床的找矿模式,进而通过对别勒滩、马海等钾盐矿例剖析,说明航空γ能潜测量在寻找第四纪盐湖型钾盐矿床方面确有明显效果。 相似文献