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1.
SUN Tao WANG Denghong LI Chao ZHANG Zengqi SUN Bin CHENG Wei LI Wanting ZHANG Aiping 《《地质学报》英文版》2020,94(2):561-562
The formation ages of global magmatic sulfide Ni-Cu deposits are from Archean to Mesozoic,the Neoarchean and Neoproterozoic are the two peaks.In China,the formation ages of magmatic sulfide deposits are from Proterozoic to Mesozoic,and the Neoproterozoic and late Paleozoic are the two peaks,.Compared with the global magmatic deposits,there is no case study of the Archean magmatic Ni-Cu sulfide deposits in China before.The nickel deposits formed in Neoproterozoic are located on the margin of the North China Block and Yangtze Block(e.g.Jinchuan,Dapoling),and those formed in the late Paleozoic are mainly distributed in the Central Asian Orogenic Belt(CAOB).Emeishan and Tarim Large Igneous Provinces(LIPs).such as Kalatongke,Yangliuping,and Pobei. 相似文献
2.
Polat Ali Frei Robert Longstaffe Fred J. Woods Ryan 《International Journal of Earth Sciences》2018,107(3):811-843
International Journal of Earth Sciences - The Neoarchean (ca. 2728 Ma) anorthosite-bearing Doré Lake Complex in the northeastern Abitibi subprovince, Quebec, was emplaced into an... 相似文献
3.
Wang Liuqi Jiang Zaixing Cao Yingchang Han Wentao Wu Jing University of Petroleum Dongying Shandong Shengli Oil Fiel Dongying Shandong Fei Zhenbi Shi Xiaoying 《《地质学报》英文版》1997,71(1):104-114
Two sequences can be identified in the sedimentary strata of the lower Tertiary ShahejieFormation in the Zhanhua hollow. The lowstand, lake-transgressive and highstand systemstracts were formed under the control of ancient structure, palaeotopography, palaeoclimate, sed-iment supply, marine-transgression, and so on. In the paper the authors present a composite se-quence stratigraphical section of the Shahejie Formation in this area, and expound the bounda-ries of parasequences, parasequences set and systems tracts and evolutions of lake sequencestratigraphy and sedimentology and discuss various factors controlling the lake level fluctuation.The differences between lake and marine sequence stratigraphy are also indicated in the paper.The lake sequence stratigraphical study should be based on a synthetic analysis of structural evo-lution, palaeomagnetism, palaeoclimatic changes, geological Well logs, seismic and logging data,palaeontological data, global sea level changes, and so on. The sequence stratigraphical evolutionis closely related to the formation, development and elimination of the whole basin and thesedimentary process. 相似文献
4.
In recent years, climate and environment changes since the Little Ice Age have become a focus in modern research. The paper selected the sediment (77 cm) of Sihu Lake, which was located in Guilin, southern China, as the research object and analyzed the karst wetland environmental changes within nearly 450 years. According to the vertical profile of indicators and geochemical elements in sediment core, the regional environmental evolution was divided into four stages. The former two stages were mainly influenced by Little Ice Age (1562–1895). The third stage climate has changed slowly. The fourth stage was mainly affected by human activities and global warming. The factor analysis of geochemical elements indicated that karst wetland regional environmental change was affected by four major factors. In the 53–77 cm stage (1562–1703), F1 (erosion factor), F2 (watershed runoff and diagenesis factor) and F3 (regional background factor) were reduced, indicating that it was in cold and dry stage of Little Ice Age. In the 20–53 cm stage (1703–1895), F1 and F2 increased, indicating that it was in cold and wet stage of Little Ice Age. In the 4–20 cm stage (1895–1987), F1, F2 and F4 (human activity factor) increased slowly, indicating that the climate was affected by global warming and more precipitation. In the 0–4 cm stage (1987–2007), F1 and F2 reduced and F4 increased, indicating the reduced precipitation, rising temperature and more impact of human activities. In addition, it was proposed that the Little Ice Age in Guilin District in southern China started in the 1560s and lasted until the 1895s or so. 相似文献
5.
The English Lake magmatic complex in the western Superior Province of Canada represents a fragment of early (3.0 Ga) continental crust exposed in oblique cross section through tonalitic upper levels and subjacent quartz diorite, diorite and gabbro, which are cut by late gabbro, anorthosite and hornblendite dykes. Massive, foliated and gneissic units of tonalitic to gabbroic composition, crystallized over a 10 to 18 m.y. period, bear common geochemical attributes, including negative Th, U and Nb anomalies, and only slight LREE and LILE enrichment on NMORB-normalized trace-element profiles. Epsilon Nd values (+0.1 to +1.7) and 18O (+6.7 to +8.0 ) do not co-vary with silica or other crustal contamination indices. High Mg#'s and Ni contents suggest derivation from, or interaction with mantle, and large positive anomalies for Ba, Sr and Pb, as well as high U/Th, suggest metasomatism by hydrous fluids. Trace-element profiles resemble those of primitive intra-oceanic island arc magmas except for the negative Th-U anomaly, which precludes the involvement of either oceanic (sedimentary or basaltic) or continental crust in the petrogenesis of English Lake magmas. In order to account for the unusual geochemical character of the suite, we postulate that water-rich fluids derived from subducted, sea-floor-altered serpentinite provided the flux for melting a depleted mantle wedge. Contemporaneous, proximal high Th/Nb tonalites suggest that the zone of serpentinite subduction occurred within a restricted arc segment possibly due to subduction of either: (a) a seamount chain oriented broadly perpendicular to an arc, or (b) a similarly oriented serpentinite-enclosed oceanic fracture zone or fault.Electronic Supplementary Material Supplementary material is available in the online version of this article at .Editorial responsibility: T.L. Grove 相似文献
6.
7.
Screening Effect of the Diffusive Boundary Layer in Sediments of Lake Aha in the Suburbs of Guiyang City,Guizhou Province 总被引:6,自引:0,他引:6
The redox cycle of iron and manganese is a major geochemica process at the boundary layers of lake sediments.Lake Aha,which lies in the suburbs of Guiyang City,Guizhou Province,China,is a medium-sized artificial reservoir with seasonally anoxic hypolimnion,Long-term sedimentary accumulation of iron and manganese resulted in their enrichment in the upper sediments,In the anoxic season,Fe^2 and Mn^2 ,formed by diological oxidation,would diffuse up to overlying waters from sediments.However,the concentration of oxidation,would diffuse up to overlying waters from sediments,However,the concentration of Fe^2 increased later and decreased earlier than that of Mn^2 .Generally,sulfate reduction occurred at 6 cm below the sediment-water interface.Whereas,in the anoxic season.the reduction reached upper sediments,inhibiting the release of Fe^2 ,The Fe concentration of anoxic water is quickly decreased from high to low as a result of reduction of the suplhur system. 相似文献
8.
Xinyu He Jionghui Wang Changming Wang Emmanuel John M Carranza Liang Chen Bin Wu 《Journal of Earth System Science》2016,125(3):585-603
The Mogou syenite intruded into the Mesoproterozoic Xiong’er Group is the main lithostratigraphic unit, along the southern margin of the North China Craton (NCC). This paper reports zircon LA-ICP-MS data, whole-rock major and trace element compositions of late Triassic magmatic rocks in the Mogou syenite, in order to constrain the formation age of the Mogou syenite, research the origin and evolution of the magma and analyse the geodynamic setting of the Qinling Orogen (QO) in Late Triassic. These rocks consist of medium- to coarse-grained syenite and fine-grained quartz syenite. Zircon U–Pb dating yields a crystallization age of 226.5±2.7 Ma. The syenites are characterized by high SiO2 (63.49–72.17%), alkali (K2O+Na2O of 11.18–15.38%) and potassium (K2O/Na2O of 2.88–28.11), are peralkaline or metaluminous (molar A/CNK of 0.87–1.02) and belong to shoshonite series. The syenites have ΣREE of 33.01–191.30 ppm, LREE/HREE of 14–20, (La/Yb)N of 11–24, with LREE-rich distribution pattern and obvious differentiation between HREE and LREE. Eu anomalies are positive for the medium- to coarse-grained syenite and weakly negative for the fine-grained quartz syenite. In addition, the syenites are enriched in large-ion lithophile elements (Ba, K, Sr, and Pb) but depleted in high strength field elements (Ti, Ta, Nb, Zr, and Hf), and have high differentiation indices of 91.69–97.06. These geochemical features indicate that the primary magma of the Mogou syenite most likely originated from a mantle source with minor crustal component, and underwent a fractional crystallization process during its emplacement. The late Triassic A-type Moguo syenite along the southern margin of the NCC was generated in the late stage of the syn-collision event of QO, recording a transition period from compression to extension at around 227 Ma. 相似文献
9.
Origin of Archean lamprophyre dykes,Superior Province,Canada: rare earth element and Nd−Sr isotopic evidence 总被引:1,自引:0,他引:1
Hornblende- and clinopyroxene-phyric lamprophyre dykes exposed in the Roaring River Complex, Superior Province are alkaline, nepheline-normative, basaltic compositions (>50 wt% SiO2), that range from primitive to fractionated [Mg/(Mg + total Fe)=0.66–0.40; Ni=200–35 ppm], and which have high abundances of light rare earth elements (REE) [(Ce/Yb)n=16–26, Cen=60–300; n = chondrite normalized], Sr (870–1,800 ppm), P2O5 (0.4–1.3 wt%), and Ba (150–900 ppm). Crystal fractionation of the lamprophyres produced coeval gabbro and clinopyroxenite cumulate bodies. A whole-rock Sm–Nd isochron for lamprophyres and gabbro-pyroxenite yields a crystallization age of 2,667±51 Ma Ma (I=0.50929±0.0004;
Nd = + 2.3 0.7). Whole-rock Sr isotope data are scattered, but suggest an initial 87Sr/86Sr ratio of 0.7012, similar to bulk Earth. The elevated levels of light REEs and Sr in the lamprophyres were not due to crustal contamination or mixing with contemporaneous monzodioritic magmas, but a result of partial melting of a mantle source which was enriched in these and other large-ion-lithophile elements (LILEs) shortly before melting. The lamprophyres were contemporaneous with mantle-derived, high-Mg, LILE-enriched monzodiorite to granodiorite of the Archean sanukitoid suite. Both suites have concave-downward light REE profiles, suggesting that depleted mantle was common to their source regions, but the higher light REE abundances, higher Ba/La ratios, and lower
Nd values (+1.3±0.3) of the parental monzodiorites suggest a more enriched source. The lamprophyres and high-Mg monzodiorites were derived from a mineralogically and compositionally heterogeneous, LILE-enriched mantle lithosphere that may have been part of a mantle wedge above a subducting plate in an arc environment. 相似文献
10.
E. V. Levashova S. G. Skublov X. H. Li S. G. Krivdik D. K. Voznyak A. A. Kulchitskaya V. I. Alekseev 《Geology of Ore Deposits》2016,58(3):239-262
The distribution of rare and rare earth elements in zircon at the Yastrebets, Azov (Zr–REE–Y), and Perzhan (Be) rare metal deposits of the Ukrainian Shield was studied. Additional evidence for magmatic genesis of these deposits is obtained: unaltered zircon is characterized by a magmatic REE distribution spectrum with a somewhat higher δ18O value than that of the mantle (6.6‰ on average). The final formation stage of the deposit was marked by predominance of fluids enriched in Y, REE, Nb, and heavy oxygen, resulting in anomalous geochemical characteristics of zircon rims and alteration zones (up to 81500 Y ppm, over 10300 ppm Nb, and 13.9‰ δ18O). The age of zircon formed in ore-bearing Yastrebets and Azov nonnepheline syenite deposits was estimated at ~1770 Ma (U–Pb, SHRIMP-II). 相似文献
11.
Detailed geological,chronological,mineralogical,petrological and geochemical studies have been conducted of the Chichent gneissic complex in northwestern Hebei province.The gneissic complex is composed mainly of tonalitic-granodioritic rocks according to O'Connor's classification.The zircou U-Pb age of the gneissic complex is 2468-27^+33 Ma.,consistent with that of the rocks in the North Tonalitic-granodioritic Gneiss Belt in the North China Platorm.The Archean Chicheng gneissic complex is part of the belt.No significant difference in composition between early anhedral metasomatic and late semi-euhedral plagiocalases suggests that the gneissic complex is not composed merely of mafic rocks replaced by felsic fiuids.The REE patterns in the complex,in conjunction with major and trace elements data,show that the gneissic complex is the mixture of felsic magma produced by partial melting of FI dacitic granulite and crystallate derived from the magma produced by 50%±partial melting of TH2 tholeiitic granulite and 40%±fractional crystallization of hornblende. 相似文献
12.
Deccan Traps spread over large parts of south, west and central India, possibly hiding underneath sediments with hydrocarbon potential. Here, we present the results of seismic refraction and wide-angle reflection experiments along three profiles, and analyze them together the results from all other refraction profiles executed earlier in the western part of Narmada–Tapti region of the Deccan Volcanic Province (DVP). We employ travel time modelling to derive the granitic basement configuration, including the overlying Trap and sub-trappean sediment thickness, if any. Travel time skips and amplitude decay in the first arrival refraction data are indicative of the presence of low velocity sediments (Mesozoic), which are the low velocity zones (LVZ) underneath the Traps. Reflection data from the top of LVZ and basement along with the basement refraction data have been used to derive the Mesozoic sediment thickness.In the middle and eastern parts of the study region between Narmada and Tapti, the Mesozoic sediment thickness varies between 0.5 and 2.0 km and reaches more than 2.5 km south of Sendhwa between Narmada and Tapti Rivers. Thick Mesozoic sediments in the eastern parts are also accompanied by thick Traps. The Mesozoic sediments along the present three profiles may not be much prospective in terms of its thickness, except inside the Cambay basin, where the subtrappean sediment thickness is about 1000–1500 m. In the eastern part of the study area, the deepest section (>4 km) has thick (∼2 km) Mesozoic sediments, but with almost equally thick Deccan Trap cover. Results of the present study provide important inputs for future planning for hydrocarbon exploration in this region. 相似文献
13.
Xiaoli QIAN Xinbin FENG Xiangyang BI 《中国地球化学学报》2006,25(B08):153-154
Caohai Lake which is situated in Guizhou Province, has suffered drain project many times since 1958.The main mercury contamination includes industry waste water, litter and waste residue from refine zinc furnace and so on. The water and sediment samples which were collected from Caohai Lake in different seasons using metal clean protocols. Study sites were selected at the upper and down reaches and the tributaries of this lake, respectively. Total mercury (THg), reactive mercury (RHg) and dissolved mercury (DHg) concentrations were measured by trap pre-concentration and CVAFS detection methods, and the concentrations of particulate mercury (PHg) are equal to difference of THg and DHg. Total methylmercury (MeH) and dissolved methylmercury (DMeHg) concentrations were measured by GC-CVAFS detection method. Mercury in sediment was measured by AAS method. The results in autumn were obtained as follows: the average concentrations of total mercury, reactive mercury, 相似文献
14.
The Uchi subprovince of the Archean Superior Province is a series of greenstone belts extending 600 km east–west along the
southern margin of the North Caribou Terrane protocontinent. The 2.7 Ga Confederation tectonostratigraphic assemblage of the
Birch–Uchi greenstone belt, northwest Ontario, is dominated by volcanic suites of mafic, intermediate and felsic composition.
Tholeiitic basalts range compositionally from Mg# 59–26 evolving continuously to greater REE contents (La=2–19 ppm; Th/Lapm˜1), with small negative Nb anomalies. Primitive tholeiites are similar to modern intraoceanic arc basalts, whereas evolved
members extend to greater concentrations of Ti, Zr, V, Sc, and Y, and lower Ti/Zr, but higher Ti/Sc and Ti/V ratios characteristic
of back arc basalts. Calc-alkaline basalts to dacites are characterised by more fractionated REE (La/Ybn=1–8), high Th/Nbpm ratios and deeper negative Nb anomalies; they plot with modern oceanic arc basalts and some may qualify as high magnesium
andesites. The two suites are interpreted as a paired arc–back arc sequence. A third group of Nb-enriched basalts (NEB; Nb=9–18 ppm)
extend to extremely high TiO2, Ta, P2O5, Sc and V contents, with strongly fractionated REE and ratios of Nb/Ta and Zr/Hf greater than primitive mantle values whereas
Zr/Sm ratios are lower. The most abundant rhyolitic suite has extremely enriched but flat trace element patterns and is interpreted
as strongly fractionated tholeiitic basalt liquids. A second group are compositionally similar to Cenozoic adakites and Archean
high-Al, high-La/Ybn tonalites; they possess Yb ≤ 0.4 ppm, Y ≤ 6 ppm and Sc ≤ 8 ppm, with La/Ybn of 19–30 and Zr/Sm of 50–59. They are interpreted as melts of ocean lithosphere basaltic crust in a hot shallow subduction
zone. Adakites are associated with NEB in Cenozoic arcs where there is shallow subduction of young and/or hot ocean lithosphere,
often with oblique subduction. Slab melt adakites erupt, or metasomatise sub-arc mantle peridotite to generate an HFSE-enriched
source that subsequently melts during induced mantle convection. The Archean adakite–NEB association erupted during development
of the tholeiitic to calc-alkaline arc and its associated back arc. Their coexistence in the Confederation assemblage of the
Birch–Uchi greenstone belt implies convergent margin processes similar to those in Cenozoic arcs.
Received: 2 June 1999 / Accepted: 29 December 1999 相似文献
15.
Yonghua LI Linsheng YANG Wuyi WANG 《中国地球化学学报》2006,25(B08):244-244
Western Hunan Province is one of the most typical assembling areas of cryogenic metallic deposit in China, as well as a main ore-forming zone for some heavy metals. In the region, Hg and Pb pollution was caused by abnormally high concentrations of Hg, Pb in the natural environment and Hg, Pb exploiting/smelting and other human activities, which make the damage to human health more complicated. Generally, heavy metal pollutants in soil are often long-lasting and consequent, with their emission and/or transport into the environment, resulting in growing hazards to human health posed by elevated heavy metal concentrations in air, water, and food. Therefore, monitoring and understanding their behaviors in soil environment is the most important and urgent task. In this paper, the environmental behaviors and pollution characteristics of soil polluted by Hg and Pb in typical Hg and Pb mining areas in western Hunan were studied. Main results are presented as follows: (1) Western Hunan Province is a high regional geochemical abnormal region on Hg and Pb. The concentrations of Hg and Pb in soils in mercury mining areas were 1 315 and 3. l times higher than the average background of soils in China, respectively. While those in soils in lead mining areas are 14.1 and 6.1 times higher. By using the index of geoaccumulation (Igeo), it was found that either mercury mining area or lead mining area in western Hunan Province has been polluted by the two elements, the majority of soils in mercury mining areas are seriously polluted by Hg, moderately or light polluted by Pb, while the majority of soils in lead mining areas are moderately or moderately-highly polluted by Pb and moderately-highly polluted by Hg. (2) By the BCR extraction procedures, both Hg and Pb in soils are dominated by residual form, followed by organic-sulfide form. Fe-Mn oxides and acid-exchangeable form are rather low. The total concentrations and each species of Hg and Pb in soils show positive correlations with the concentrations of sands, and negative ones with the concentrations of clays in soils. 相似文献
16.
The Shexian gneissic granodiorite in southern Anhui trends NE 55° from Shexian in the west to Guitoujian in the east with
a length of 22 km and an outcrop area of 32 km. It was considered formerly to be Caledonian on the basis of a biotite K-Ar
age of 474 Ma (1982). However, new evidence indicates that it may be Early Jinning in age as shown by: (1) it is found intruding
into the Mid-Proterozoic Shangxi Group and is unconformably overlain by the Sinian Xiuning Formation, and (2) a zircon U-Th-Pb
age of 928 Ma is obtained for the pluton.
The pluton is composed of plagioclase (An=27.37%), K-feldspar(14%), biotite(16%) and quartz(32%). Accessory minerals are ilmenite
(150g/T), xenotime (15g/T). garnet(25g/T), monazite(10g/T), zircon (20g/T) and apatite (104g/T). Petrochemical characteristics
of the intrusion are:(l) Al-enrichment (A/NKC=1.30); (2) H2O enrichment (H2O= 1.74%); and (3) low oxidation index (f ’=0.10). It belongs to the continental crust transformation type as evidenced by: (1) MF and Mg/Y values of biotite are 0.41
and 0.31 respectively; (2) (87Sr/86Sr)=0.71119; (3) δ Eu=0.52; and (4) A/NKC=130. The Shexian pluton is therefore considered as a product of melting of phyllite
at depth in the light of similarities in trace element and REE contents with the phyllite of the Banxi Group. Calculations
of REE batch partial melting indicate that it may have resulted from 75% melting of the Banxi phyllite. 相似文献
17.
《Journal of Structural Geology》2003,25(10):1675-1689
We analyze pervasive and discontinuous deformation associated with small faults in a quartz–syenite body in southern Israel. The analysis includes detailed mapping, measurement of in-situ mechanical rock properties and microstructural study of the faults. The mapped faults have 1–100-m-long horizontal traces, consisting of linked, curved segments; the segmented nature of the faults is also apparent at the 1–10 mm scale. The observed deformation features are breccia, as well as intra- and inter-granular fractures; these features are accompanied by reduction of the Young modulus and uniaxial strength of the host rock. The deformation features are zoned from a central fault-core through a damage-zone to the protolith at distances of 0.05–0.06 the fault length. Shear strains up to 300% were calculated from measured marker lines displacements and distortion in proximity to the faults. We argue here that the fault-related deformation during fault propagation is manifested by highly localized deformation in a process zone having a width of 0.001–0.005 of the fault length (fault-related deformation due to subsequent slip along the existing faults is analyzed in Part II). The observed self-similarity of the discontinuities over five length orders of magnitude and the outstanding lack of tensile microcracks suggest fault initiation and growth as primary shear fractures. 相似文献
18.
The Archean granites exposed in the Mesorchean Rio Maria granite-greenstone terrane (RMGGT), southeastern Amazonian craton can be divided into three groups on the basis of petrographic and geochemical data. (1) Potassic leucogranites (Xinguara and Mata Surrão granites), composed dominantly of biotite monzogranites that have high SiO2, K2O, and Rb contents and show fractionated REE patterns with moderate to pronounced negative Eu anomalies. These granites share many features with the low-Ca granite group of the Yilgarn craton and CA2-type of Archean calc-alkaline granites. These granites result from the partial melting of rocks similar to the older TTG of the RMGGT. (2) Leucogranodiorite-granite group (Guarantã suite, Grotão granodiorite, and similar rocks), which is composed of Ba- and Sr-rich rocks which display fractionated REE patterns without significant Eu anomalies and show geochemical affinity with the high-Ca granite group or Transitional TTG of the Yilgarn craton and the CA1-type of Archean calc-alkaline granites. These rocks appear to have been originated from mixing between a Ba- and Sr-enriched granite magma and trondhjemitic liquids or alternatively product of interaction between fluids enriched in K, Sr, and Ba, derived from a metasomatized mantle with older TTG rocks. (3) Amphibole-biotite monzogranites (Rancho de Deus granite) associated with sanukitoid suites. These granites were probably generated by fractional crystallization and differentiation of sanukitoid magmas enriched in Ba and Sr.The emplacement of the granites of the RMGGT occurred during the Mesoarchean (2.87–2.86 Ga). They are approximately coeval with the sanukitoid suites (∼2.87 Ga) and post-dated the main timing of TTG suites formation (2.98–2.92 Ga). The crust of Rio Maria was probably still quite warm at the time when the granite magmas were produced. In these conditions, the underplating in the lower crust of large volumes of sanukitoid magmas may have also contributed with heat inducing the partial melting of crustal protoliths and opening the possibility of complex interactions between different kinds of magmas. 相似文献
19.
Enzymatic and Microbial Degradation of Organic Matter in Lake Hongfeng, Guizhou Province, China 总被引:1,自引:2,他引:1
1IntroductionEnzymaticandmicrobialdegradationoforganicmatterhasabearingnotonlyonearlydiagene sis,butalsoonelementcyclingandmicrobedistributioninlakesediments.Somereportsshowedtheabundancevariationsoforganicmatterinsediments (BurdigeandGardner,1998;ArthurandDean ,1998;WanGuojiangetal.,2 0 0 0 ) .However,duetothecomplexchemicalcompositionoforganicmatter,mechanismsofenzymaticandmicrobialdegradationandvariationsofeachchemicalcomponentneedtobestudiedfurther.Underanoxiccondition ,SO2 -4 isanimpo… 相似文献
20.
《地质与勘探》2012,48(3)
郁山铝土矿矿床是豫西典型的隐伏铝土矿床,本文以西郁山矿段为主较系统阐述了矿床地质、矿体和矿石特征等。矿体赋存于本溪组铁铝质泥岩建造中下覆马家沟组岩溶特征控制矿体的形态,矿体深部延伸受架子沟背斜及断层控制,其上覆地层控制矿体的埋深。矿体厚度空间变化大,A/S与含铝岩系厚度及矿体厚度相关性很小。矿石以鲕粒和泥晶结构为主,少部分具有"砾中鲕"结构,显示矿床形成过程中的风化与搬运的复合过程。矿石主要含铝矿物是一水硬铝石(42%~88%),其次是粘土矿物(高岭石和伊利石);黄铁矿、菱铁矿较普遍分布于下部矿石中,显示矿石形成于还原性沉积洼地中。铝土矿共伴生有益矿产和元素价值大。本文对进一步研究河南省隐伏铝土矿床有较重要参考意义。 相似文献