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1.
本文首次研究了山东金伯利岩中橄榄石的产状、含量、大小、世代、形态、颜色、
环带、矿物包体、折光率、2V、化学成分、端员组分特征及红外光谱和穆斯堡尔谱特征，并分
析研究了橄榄石的成因。指出了无色一浅绿色的、含MgO、Cr2O3. Ni0高的橄榄石是找金刚石
矿的指示性矿物。 相似文献
2.
本文研究了2个富钙长石-橄榄石型包体和2个富黄长石-尖晶石型和富尖晶石-辉石型包体（分别来自宁强和南极格罗夫山碳质球粒陨石）的矿物岩石学特征,并对它们进行了对比。富钙长石-橄榄石型包体的矿物模式组成具有富橄榄石和缺失黄长石的特征,其可能是球粒和典型难熔包体之间的中间产物,是认识它们之间相互关系的钥匙。矿物岩石学特征表明富黄长石-尖晶石型和富尖晶石-辉石型包体可能是星云直接凝聚的产物,而富钙长石-橄榄石型包体经历过熔融结晶过程。富钙长石-橄榄石型包体的初始物质可能是富Al的球粒或含难熔组分的蠕虫状橄榄石集合体。矿物化学组成对比研究发现,GRV 022459-RI6中的尖晶石具有最富FeO的特征,表明包体的蚀变可能发生在高氧逸度的星云环境。 相似文献
3.
本岩体中橄榄石矿物特征的研究资料已有较多的记载,尤其是最近几年,又更多地描述了橄榄石晶体的方位定向性,以及该矿物的带状消光和笔者提出的2V值异常等应力作用特征。反映了橄榄石矿物是在一定的物理化学条件中受应力作用而形成的,并且这种应力作用所形成的痕迹(系指晶体定向、带状消光和2V值异常),在橄榄石矿物中永久地保存下来了。本文对橄榄石矿物晶体所受应力作用的机制进行了分析讨论,并结合岩体地质概况提出本岩体的最终侵位方式是冷侵位的见解。应当指出,笔者仅仅是着重从岩体侵位过程的应力特点出发,而不过多地涉及其它地质因素。由于笔者水平有限,以及超基性岩体侵位方式 相似文献
4.
哀牢山南段蛇绿岩中变质橄榄石单元,由方辉橄榄石和二辉橄榄岩组成,前者已强烈蚀变,后者的矿物组成有橄榄石,斜方辉石,单斜辉石及少量尖晶石等,对这些矿物进行了较详细的化学成分分析,橄榄石,斜方辉石的化学分显示,二辉橄榄石为较弱亏损的地幔岩,橄榄石,尖晶石的矿物化学反应,变质橄榄石的原始岩石具有深海橄榄石的特征,单斜辉石,尖晶石的化学特征显示,二辉橄榄石经历过程熔融作用,因此,二辉橄榄石为部分熔融较弱亏 相似文献
5.
通过偏光显微镜、电子探针、X射线粉末衍射、傅里叶变换红外光谱、X射线荧光光谱、微量元素测试等对丹东绿玉石样品进行了常规矿物学、谱学特征研究。结果表明,丹东绿玉石是以蛇纹石为主要矿物,镁橄榄石、白云石、水镁石、绿泥石、伊利石为次要矿物的蛇纹石化镁橄榄石矽卡岩。 相似文献
6.
月表主要矿物的空间分布是研究月球起源及演化等科学问题的重要信息之一.以风暴洋地区为例, 根据不同矿物光谱在可见光-近红外波段的吸收特征, 使用印度M3(moon mineralogy mapper)数据, 应用波谱特征拟合法(SFF)反演了火山口附近暗物质区域的单斜辉石、斜方辉石、橄榄石和尖晶石等铁镁质矿物的分布, 反演结果显示: 风暴洋地区提取的铁镁质矿物分布较集中, 其中辉石含量较多, 橄榄石和尖晶石含量相对较少.另外着重分析了橄榄石、尖晶石与周围矿物的关系及其地质意义.将提取结果与Lucey用于Clementine影像的光学模型填图结果进行对比显示, 提取的橄榄石分布集中, 但不存在大尺度的分布, 这与本文的研究区域面积有关; 就位置而言, 二者具有较好的一致性. 相似文献
7.
含镁硅酸盐矿物是重要自然资源,国内外大都采用传统的化学方法进行开发利用,而微生物法释放含镁硅酸盐矿物中镁和硅的研究还未见报道。试验采用摇瓶培养与对照结合的方法研究烟曲霉(Aspergillusfumigatus)对含镁硅酸盐矿物——蛇纹石和橄榄石的风化作用。试验采用ICP-OES测定第5、10、20、30 d培养液滤液中Mg2+和Si的含量,同时对相应试样的pH值和代谢产物进行分析测定,采用SEM和TEM观察作用后的微生物-矿物聚集体。结果表明,烟曲霉作用蛇纹石和橄榄石试样滤液中的Mg2+和Si含量变化不仅与烟曲霉生长状况有关,而且与矿物的晶体结构相关,蛇纹石较橄榄石更易被烟曲霉风化;另外烟曲霉在生长过程中产生的酸性代谢产物有助于对矿物的风化;SEM和TEM观察结果直观地显示出烟曲霉对蛇纹石和橄榄石的风化作用痕迹。综合分析认为,烟曲霉对蛇纹石和橄榄石的风化作用应该是酸溶作用、菌丝对矿物的穿插包裹和菌丝体对养分的吸收等方式协同作用的综合效果。研究结果为探讨真菌与矿物相互作用的过程与机理以及为微生物法开发蛇纹石和橄榄石矿产资源提供了基础资料。 相似文献
8.
地幔橄榄岩是罗布莎蛇绿岩的主要组成成分之一,通过显微构造特征可对其变形特征进行分析,确定流变学参数,探讨地幔橄榄岩的变形历史。以蛇纹石化程度较低的二辉橄榄岩和方辉橄榄岩为研究对象,橄榄石位错特征研究显示,本区橄榄石主要发育了低温常见的直线型自由位错,局部可见位错弓弯、位错环、位错壁等高温位错,反映罗布莎地幔橄榄岩变形以低温塑性流变为主,局部经历了高温塑性流变,主导变形机制为位错蠕变。橄榄石自由位错统计结果表明,二辉橄榄岩中的橄榄石自由位错密度为4.422×107/cm2,方辉橄榄岩中的橄榄石为9.137×107/cm2,变形过程中所受差异应力分别为65MPa和93MPa。橄榄石和斜方辉石显微组构测量采用了电子背散射衍射技术(EBSD),分析结果表明,橄榄石均发育A型组构,为浅部地幔常见的组构类型,该结果与金刚石、柯石英等超高压矿物所指示的形成深度不一致。 相似文献
9.
通过国内２０个含铬铁矿、铜镍矿和饥钛磁铁矿的基性、超基性岩体中６８个橄榄石化学成分、产出状态、地球化学特征、有序度和岩浆包裹体橄榄石子矿物、温度、压力等标型特征研究显示，产于不同矿化基性、超基性岩中橄榄石的标型特征明显不同，为找寻铬铁矿、铜镍矿和钒钛磁铁矿矿产提供重要标志。 相似文献
10.
富Ca,Al包体、球粒和蠕虫状橄榄石集合体都是早期星云事件的产物。本文探讨了4个富橄榄石的富Ca,Al组分集合体的矿物岩石学特征,并对它们进行了对比。矿物岩石学特征表明含橄榄石边的富尖晶石-辉石型包体和富Ca,Al组分蠕虫状橄榄石集合体都属于星云直接凝聚的产物,而富钙长石-橄榄石型包体(POI)和富Ca,Al组分球粒经历过熔融结晶过程。矿物模式组成表明POI包体和富Ca,Al组分球粒可能是认识典型富Ca,Al包体与球粒之间相互关系的钥匙。蠕虫状橄榄石集合体GRV022459-2C1中尖晶石普遍具有高的FeO含量,表明其蚀变发生于高氧逸度的星云环境。球粒与粗粒富Ca,Al包体可能属于同一热事件的产物,粗粒富Ca,Al包体形成于富Ca,Al矿物富集的区域,Mg,Fe质硅酸盐球粒形成于富Ca,Al矿物缺失的区域,POI包体和富Ca,Al组分球粒可能形成于上述两个区域之间的过渡区域。 相似文献
11.
Olivine in kimberlites can provide unique insights into magma petrogenesis, because it is the most abundant xenocrystic phase and a stable magmatic product over most of the liquid line of descent. In this study we examined the petrography and chemistry of olivine in kimberlites from different tectonic settings, including the Slave craton, Canada (Ekati: Grizzly, Koala), the Brasilia mobile belt (Limpeza-18, Tres Ranchos-04), and the Kaapvaal craton, South Africa (Kaalvallei: Samada, New Robinson). Olivine cores display a wide range of compositions (e.g., Mg# = 78–95). The similarity in olivine composition, resorption of core zones and inclusions of mantle-derived phases, indicates that most olivine cores originated from the disaggregation of mantle peridotites, including kimberlite-metasomatised lithologies (i.e. sheared lherzolites and megacrysts). Olivine rims typically show a restricted range of Mg#, with decreasing Ni and increasing Mn and Ca contents, a characteristic of kimberlitic olivine worldwide. The rims host inclusions of groundmass minerals, which implies crystallisation just before and/or during emplacement. There is a direct correlation between olivine rim composition and groundmass mineralogy, whereby high Mg/Fe rims are associated with carbonate-rich kimberlites, and lower Mg/Fe rims are correlated with increased phlogopite and Fe-bearing oxide mineral abundances. There are no differences in olivine composition between explosive (Grizzly) and hypabyssal (Koala) kimberlites. Olivine in kimberlites also displays transitional zones and less common internal zones, between cores and rims. The diffuse transitional zones exhibit intermediate compositions between cores and rims, attributed to partial re-equilibration of xenocrystic cores with the ascending kimberlite melt. In contrast, internal zones form discrete layers with resorbed margins and restricted Mg# values, but variable Ni, Mn and Ca concentrations, which indicates a discrete crystallization event from precursor kimberlite melts at mantle depths. Overall, olivine exhibits broadly analogous zoning in kimberlites worldwide. Variable compositions for individual zones relate to different parental melt compositions rather than variations in tectonic setting or emplacement mechanism. 相似文献
12.
Olivine is the principal mineral of kimberlite magmas, and isthe main contributor to the ultramafic composition of kimberliterocks. Olivine is partly or completely altered in common kimberlites,and thus unavailable for studies of the origin and evolutionof kimberlite magmas. The masking effects of alteration, commonin kimberlites worldwide, are overcome in this study of theexceptionally fresh diamondiferous kimberlites of the Udachnaya-Eastpipe from the Daldyn–Alakit province, Yakutia, northernSiberia. These serpentine-free kimberlites contain large amountsof olivine (50 vol.%) in a chloride–carbonate groundmass.Olivine is represented by two populations (olivine-I and groundmassolivine-II) differing in morphology, colour and grain size,and trapped mineral and melt inclusions. The large fragmentalolivine-I is compositionally variable in terms of major (Fo 85–94)and trace element concentrations, including H 2O content (10–136ppm). Multiple sources of olivine-I, such as convecting andlithospheric mantle, are suggested. The groundmass olivine-IIis recognized by smaller grain sizes and perfect crystallographicshapes that indicate crystallization during magma ascent andemplacement. However, a simple crystallization history for olivine-IIis complicated by complex zoning in terms of Fo values and traceelement contents. The cores of olivine-II are compositionallysimilar to olivine-I, which suggests a genetic link betweenthese two types of olivine. Olivine-I and olivine-II have oxygenisotope values (+ 5·6 ± 0·1 VSMOW, 1 SD)that are indistinguishable from one another, but higher thanvalues (+ 5·18 ± 0·28) in ‘typical’mantle olivine. These elevated values probably reflect equilibriumwith the Udachnaya carbonate melt at low temperatures and 18O-enrichedmantle source. The volumetrically significant rims of olivine-IIhave constant Fo values (89·0 ± 0·2 mol%),but variable trace element compositions. The uniform Fo compositionsof the rims imply an absence of fractionation of the melt'sFe 2+/Mg, which is possible in the carbonatite melt–olivinesystem. The kimberlite melt is argued to have originated inthe mantle as a chloride–carbonate liquid, devoid of ‘ultramafic’or ‘basaltic’ aluminosilicate components, but becameolivine-laden and olivine-saturated by scavenging olivine crystalsfrom the pathway rocks and dissolving them en route to the surface.During emplacement the kimberlite magma changed progressivelytowards an original alkali-rich chloride–carbonate meltby extensively crystallizing groundmass olivine and gravitationalseparation of solids in the pipe. KEY WORDS: kimberlite; olivine; partial melting; carbonatitic melt; oxygen isotopes; H2O 相似文献
13.
Petrographic and chemical criteria indicate that the overwhelming majority of olivines in kimberlites are probably cognate phenocrysts. The implied low volume of xenocryst olivines requires that primitive kimberlite magmas are highly ultrabasic liquids. Two chemically distinctive olivine populations are present in all of the kimberlites studied. The dominant olivine population, which includes large rounded olivines and smaller euhedral crystals, is Mg-rich relative to late-stage rim compositions. It is characterized by a range in 100 Mg/(Mg + Fe) and uniform Ni concentration, reflecting Rayleigh-type crystallization during magma evolution. The most Mg-rich of these olivines are considered to be similiar to those in the mantle source rocks. The second compositional population, generally very subordinate, though markedly more abundant in the megacrystrich Monastery kimberlite, is Fe-rich relative to rim compositions. This group of olivines crystallized from evolved liquids in equilibrium with iron-rich megacrysts, both entrained by the kimberlite magma during ascent. Differences between the chemical fields of Fe-rich olivines in Group I and Group II kimberlites point to relatively deeper derivation of the latter suite. Olivine chemistry can be used to characterize kimberlite magma sub-types, and may prove to be a useful tool for evaluating the diamond potential of kimberlites. 相似文献
14.
Distinctly different groundmass mineralogy characterise the hypabyssal facies, Mesoproterozoic diamondiferous P3 and P4 intrusions from the Wajrakarur Kimberlite Field, southern India. P3 is an archetypal kimberlite with macrocrysts of olivine and phlogopite set in a groundmass dominated by phlogopite and monticellite with subordinate amounts of serpentine, spinel, perovskite, apatite, calcite and rare baddeleyite. P4 contains mega- and macrocrysts of olivine set in a groundmass dominated by clinopyroxene and phlogopite with subordinate amounts of serpentine, spinel, perovskite, apatite, and occasional gittinsite, and is mineralogically interpreted as an olivine lamproite. Three distinct populations of olivine, phlogopite and clinopyroxene are recognized based on their microtextural and compositional characteristics. The first population includes glimmerite and phlogopite–clinopyroxene nodules, and Mg-rich olivine macrocrysts (Fo 90–93) which are interpreted to be derived from disaggregated mantle xenoliths. The second population comprises macrocrysts of phlogopite and Fe-rich olivine (Fo 81–89) from P3, megacrysts and macrocrysts of Fe-rich olivine (Fo 85–87) from P4 and a rare olivine–clinopyroxene nodule from P4 which are suggested to have a genetic link with the precursor melt of the respective intrusions. The third population represents clearly magmatic minerals such as euhedral phenocrysts of Fe-rich olivine (Fo 85–90) crystallised at mantle depths, and olivine overgrowth rims formed contemporaneously with groundmass minerals at crustal levels. Close spatial association and contemporaneous emplacement of P3 kimberlite and P4 lamproite is explained by a unifying petrogenetic model which involves the interaction of a silica-poor carbonatite melt with differently metasomatised wall rocks in the lithospheric mantle. It is proposed that the metasomatised wall rock for lamproite contained abundant MARID-type and phlogopite-rich metasomatic veins, while that for kimberlite was relatively refractory in nature. 相似文献
15.
Early Proterozoic kimberlites of Karelia are among the most ancient diamond-bearing primary source rocks in the world. They compose the large (2.0 × 0.8 km) Kimozero body localized in the predicted Zaonezhskoe kimberlite field. The established and assumed occurrences of kimberlite magmatism are located within the Karelian craton, which was stabilized during the Early Archean. They are confined to the central part of a large geophysical anomaly detected by gravity, magnetic, seismic, and heat-flow studies and mark a deep-seated magma chamber. Kimberlite bodies occur within structural blocks bounded by zones of plicative-rupture dislocations.The Kimozero kimberlites form an extensive but thin saucer-like body cut by narrow quasi-cylindrical feeders and dikes. It consists of metamorphosed kimberlites, their breccias and tuffs with widely varying amounts of mica. The body includes fragmentary fine-layered crater formations. The rocks contain olivine and phlogopite phenocrysts in an extremely altered groundmass of serpentine, chlorite, calcite, mica, and ore minerals as well as indicator minerals of kimberlites, such as Cr-spinel, manganiferous ilmenite, Cr-diopside, and rare pyrope. About 100 diamonds were extracted from 12 samples (total weight 815 kg). The crystals are colorless resorbed octahedra and, more seldom, combined octahedra-dodecahedra and spinel twins with abundant green spots caused by natural irradiation, which often make the whole crystal surface green. The diamonds contain inclusions of Mg-rich orthopyroxene and pentlandite suggestive of peridotitic lithospheric mantle derivation and dating of the sulfide inclusion implies a late Archean mantle source. By petrochemistry, the rocks are classified as kimberlites.The Kimozero kimberlites differ from classical Phanerozoic ones in having higher Fe contents, low contents of alkalies and P 2O 5, and intense superimposed carbonate, magnetite, and amphibole mineralization. The saucer-like bodies with narrow feeders without developed diatremes have no analogs in Russia but are similar to the saucer-like kimberlite bodies in Canada (Fort a la Corne), India (Tokapal), and Central Africa (Bakwanga) and the West Kimberley lamproites in Australia. By analogy with these bodies and on the basis of some common petrographic features (presence of pyroclastics and specific amoeba-like autoliths, scarcity of fragments of the enclosing rocks, local reworking of the deposited matter), the Kimozero kimberlites are considered to be the products of subaerial volcanic central-type eruptions. 相似文献
16.
The Cambrian Gahcho Kué kimberlite cluster includes four main pipes that have been emplaced into the Archaean basement granitoids of the Slave Craton. Each of the steep-sided pipes were formed by the intrusion of several distinct phases of kimberlite in which the textures vary from hypabyssal kimberlite (HK) to diatreme-facies tuffisitic kimberlite breccia (TKB). The TKB displays many diagnostic features including abundant unaltered country rock xenoliths, pelletal lapilli, serpentinised olivines and a matrix composed of microlitic phlogopite and serpentine without carbonate. The HK contains common fresh olivine set in a groundmass composed of monticellite, phlogopite, perovskite, serpentine and carbonate. A number of separate phases of kimberlite display a magmatic textural gradation from TKB to HK, which is characterised by a decrease in the proportion of pelletal lapilli and country rock xenoliths and an increase in groundmass crystallinity, proportion of fresh olivine and the degree of xenolith digestion. The pipe shapes and infills of the Gahcho Kué kimberlites are similar to those of the classic South African pipes, particularly those of the Kimberley area. Similar intrusive magmatic emplacement processes are proposed in which the diatreme-zone results from the degassing, after breakthrough, of the intruding magma column. The transition zones represent ‘frozen’ degassing fronts. The style of emplacement of the Gahcho Kué kimberlites is very different from that of many other pipes in Canada such as at Lac de Gras, Fort à la Corne or Attawapiskat. 相似文献
17.
This paper reviews key characteristics of kimberlites on the Ekati property, NWT, Canada. To date 150 kimberlites have been discovered on the property, five of which are mined for diamonds. The kimberlites intrude Archean basement of the central Slave craton. Numerous Proterozoic diabase dykes intrude the area. The Precambrian rocks are overlain by Quaternary glacial sediments. No Phanerozoic rocks are present. However, mudstone xenoliths and disaggregated sediment within the kimberlites indicate that late-Cretaceous and Tertiary cover (likely <200 m) was present at the time of emplacement. The Ekati kimberlites range in age from 45 to 75 Ma. They are mostly small pipe-like bodies (surface area mostly <3 ha but up to 20 ha) that typically extend to projected depths of 400–600 m below current surface. Pipe morphologies are strongly controlled by joints and faults. The kimberlites consist primarily of variably bedded volcaniclastic kimberlite (VK). This is dominated by juvenile constituents (olivine and lesser kimberlitic ash) and variable amounts of exotic sediment (primarily mud), with minor amounts of xenolithic wall-rock material (generally <5%). Kimberlite types include: mud-rich resedimented VK (mRVK); olivine-rich VK (oVK); sedimentary kimberlite; primary VK (PVK); tuffisitic kimberlite (TK) and magmatic kimberlite (MK). The presence and arrangement of these rock types varies widely. The majority of bodies are dominated by oVK and mRVK, but PVK is prominent in the lower portions of certain kimberlites. TK is rare. MK occurs primarily as precursor dykes but, in a few cases, forms pipe-filling intrusions. The internal geology of the kimberlites ranges from simple single-phase pipes (RVK or MK), to complex bodies with multiple, distinct units of VK. The latter include pipes infilled with steep, irregular VK blocks/wedges and at least one case in which the pipe is occupied by well-defined sub-horizontal VK phases, including a unique, 100-m-thick graded sequence. The whole-rock compositions of VK samples suggest significant loss of kimberlitic fines during eruption followed by variable dilution by surface sediment and concurrent incorporation of kimberlitic ash. Diamond distribution within the kimberlites reflects the amount and nature of mantle material sampled by individual kimberlite phases, but is modified considerably by eruption and depositional processes. The characteristics of the Ekati kimberlites are consistent with a two-stage emplacement process: (1) explosive eruption/s causing vent clearing followed by formation of a significant tephra rim/cone of highly fragmented, olivine-enriched juvenile material with varying amounts of kimberlitic ash and surface sediments (predominantly mud); and (2) infilling of the vent by direct deposition from the eruption column and/or resedimentation of crater rim materials. The presence of less fragmented, juvenile-rich PVK in the lower portions of certain pipes and the intrusion of large volumes of MK to shallow levels in some bodies suggest emplacement of relatively volatile-depleted, less explosive kimberlite in the later stages of pipe formation and/or filling. Explosive devolatilisation of CO 2-rich kimberlite magma is interpreted to have been the dominant eruption mechanism, but phreatomagmatism is thought to have played a role and, in certain cases, may have been dominant. 相似文献
18.
This paper reports new petrographic and mineralogical data on the Manchary kimberlite pipe, which was discovered south of Yakutsk (Central Yakutia) in 2007–2008, 100 km. The pipe breaks through the Upper Cambrian carbonate deposits and is overlain by Jurassic terrigenous rock masses about 100 m thick. It is composed of greenish-gray kimberlite breccia with a serpentine-micaceous cement of massive structure. The porphyry texture of kimberlite is due to the presence of olivine, phlogopite, and picroilmenite phenocrysts. The SiO 2 and Al 2O 3 contents of the groundmass are indicative of typical noncontaminated kimberlites. The groundmass has a significant content of ore minerals: Fe- and Cr-spinels, perovskite, magnetite, and, less commonly, magnesian Cr-magnetite. Pyropes occur in kimberlites as sharp-edged fragments and show uneven distribution. Chemically, they belong to lherzolite, wehrlite, or nondiamondiferous dunite–harzburgite parageneses. Garnets corresponding to lherzolites of anomalous composition make up 8%; this is close to the garnet content of Middle Paleozoic kimberlites from the Yakutian kimberlite province. The pyropes from the new pipe are compositionally similar to those from diamond-poor Middle Paleozoic kimberlites in the north of the Yakutian diamondiferous province. Chemically, pyropes from the Manchary pipe and those from the modern alluvium of the Kengkeme and Chakyya Rivers differ substantially. Consequently, the rocks of the pipe could not be a source of pyropes for this alluvium. They probably occured from other sources. This fact along with numerous “pipelike” geophysical anomalies, suggest the existence of a new kimberlite field in Central Yakutia. 相似文献
19.
本文研究了金伯利岩中,作为巨晶和粗晶,基质相矿物,与金云母、镁铝榴石、铬尖晶石等矿物的连生体,金刚石中包裹体矿物及金伯利岩地幔岩包裹体矿物产出的钛铁矿的大小,形态、皮壳及化学成分、端元组分、环带及成分变异趋势。并与其他岩类中的钛铁矿作了对比。探讨了不同产状、共生组合类型的钛铁矿的成因。指出了与金刚石紧密伴生的钛铁矿的标型特征及找矿意义。 相似文献
20.
辽南金伯利岩岩区是我国最大的原生金刚石矿产区，该区金刚石主要寄主岩石类型为斑状金伯利岩。橄榄石是金伯利岩中最重要的造岩矿物，根据其结构特征可以分为橄榄石粗晶、橄榄石斑晶以及基质中微细粒三个世代。本文将岩相学特征和前人研究成果相结合，构建辽南斑状金伯利岩岩浆起源、上升、喷发和成岩模型，探讨各世代矿物的形成过程。具体包括：深部交代地幔部分熔融，形成初始碳酸盐岩浆；初始岩浆上升过程中捕获的岩石圈地幔橄榄岩不断溶解(形成橄榄石粗晶)，岩浆成分发生改变，成为金伯利岩岩浆；金伯利岩岩浆迅速上升侵位，至地表处爆破喷发，最后冷却固结形成包含粗晶及其他两个世代橄榄石的斑状金伯利岩。 相似文献
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