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1.
New geochemical data are discussed on the magmatic complexes of the Koksharovka alkaline ultrabasic massif of Late Jurassic
age obtained by the ICP-MS method. Based on the first results on rare earth geochemistry of carbonatites and associating pyroxenites
and geological observations, the magmatic origin of the Koksharovka carbonatites was substantiated, and the problems of formation
of accompanying igneous rocks were considered. 相似文献
3.
The Devonian (ca. 385–360 Ma) Kola Alkaline Province includes 22 plutonic ultrabasic–alkaline complexes, some of which also contain carbonatites and rarely phoscorites. The latter are composite silicate–oxide–phosphate–carbonate rocks, occurring in close space-time genetic relations with various carbonatites. Several carbonatites types are recognized at Kola, including abundant calcite carbonatites (early- and late-stage), with subordinate amounts of late-stage dolomite carbonatites, and rarely magnesite, siderite and rhodochrosite carbonatites. In phoscorites and early-stage carbonatites the rare earth elements (REE) are distributed among the major minerals including calcite (up to 490 ppm), apatite (up to 4400 ppm in Kovdor and 3.5 wt.% REE 2O 3 in Khibina), and dolomite (up to 77 ppm), as well as accessory pyrochlore (up to 9.1 wt.% REE 2O 3) and zirconolite (up to 17.8 wt.% REE 2O 3). Late-stage carbonatites, at some localities, are strongly enriched in REE (up to 5.2 wt.% REE 2O 3 in Khibina) and the REE are major components in diverse major and minor minerals such as burbankite, carbocernaite, Ca- and Ba-fluocarbonates, ancylite and others. The rare earth minerals form two distinct mineral assemblages: primary (crystallized from a melt or carbohydrothermal fluid) and secondary (formed during metasomatic replacement). Stable (C–O) and radiogenic (Sr–Nd) isotopes data indicate that the REE minerals and their host calcite and/or dolomite have crystallized from a melt derived from the same mantle source and are co-genetic. 相似文献
4.
A systematic and rational nomenclature of minerals of the pyrochlore group are developed based on the results obtained by processing 671 chemical analyses of pyrochlore-group minerals from carbonatite complexes, alkali rocks, and their pegmatites, granite pegmatites, and alkali and albitized granites. The proportions of Nb, Ta, and Ti are typomorphic of pyrochlore from these four types of geological environments. The paper lists pervasive characteristics of the distribution of Na and Ca, REE, Th and U, Sr and Ba, K and Cs, Pb, Sn, Sb, and Bi in the minerals. Based on the occurrence of compositions with elevated concentrations of typomorphic elements at site B in the structure of the minerals, pyrochlore subspecies are recognized: pyrochlore, Ta-pyrochlore, Ta,Ti-pyrochlore, Zr-pyrochlore, Nb-betafite, Ta-betafite, Ti-betafite, Ti-microlite, Nb,Ti-microlite, Nb-microlite, and microlite, as well as 60 geochemically significant varieties with the predominance of certain cations at site A (REE-pyrochlore, U-pyrochlore, etc.). Aspects of a rational systematics of minerals of complicated isomorphic series are discussed. 相似文献
5.
X-ray diffraction analysis and transmission electron microscopy have been used to study the effects of alpha-decay damage in pyrochlore group minerals, characterized by the general formula A 1?m B 2O 6(O,OH,F) 1?n · pH 2O. As defined by the XRD intensity ratio I/I 0 , both the saturation dose (for which I/I 0 =0.1?0.0) and the dose which signifies the initial loss of crystallinity (for which I/I 0 =1.0?0.8) increase as a function of geologic age. The increase is attributed to annealing of isolated alpha-recoil tracks back to the original crystalline structure. The tracks have calculated mean lives, τ a, on the order of 10 8 years. In contrast, minerals which remain crystalline (e.g., uraninite, UO 2) despite doses of up to 10 18 alpha-events/mg have mean alpha-recoil track lives ≈10 4 years (Eyal and Fleischer 1985). After correcting the calculated dose for annealing of alpha-recoil damage, I/I 0 is observed to decrease exponentially to zero over the dose range 0.02–1.0 × 10 16 alpha-events/mg. The relationship between I/I 0 and “corrected” dose was used to calculate an average alpha-recoil track diameter of 4.6 nm, in which < 2600 atoms are displaced. XRD line broadening due to strain dominates the first half of the crystalline-to-metamict transition, reaching a maximum of 0.003, then decreasing to < 0.001. Line broadening due to decreasing crystallite size dominates the latter half of the transition. Estimated crystallite dimensions decrease from 450 nm to < 15 nm prior to reaching the fully metamict state. With increasing dose HRTEM images of microlites from the Harding pegmatite sequentially exhibit: 1) mottled diffraction contrast, 2) isolated 1–5 nm aperiodic areas, 3) coexisting aperiodic and crystalline areas, 4) relict “islands” of crystalline material in an aperiodic matrix, and 5) complete loss of lattice fringe periodicity. With no consideration given to alpha-recoil track fading, the transition covers a dose range of 0.04–1.7 × 10 17 alpha-events/mg. Using a value of τ a=10 8 years, this dose range is corrected down to 0.02–1.2 × 10 16 alpha-events/mg. The metamict state is characterized by a range of M-M and M-O distances which give rise to bands of diffuse scattering centered at 0.30 nm and 0.18 nm, respectively, in x-ray and electron diffraction patterns. Random image contrast shown by HRTEM is consistent with a random network type structure, an interpretation supported by EXAFS/ XANES studies (Greegor et al. 1985a, b, 1987). The structure of metamict pyrochlore consists of an aperiodic framework of corner-sharing B-O polyhedra. Compared to the crystalline precursor, the metamict state displays a reduced M-O coordination number and mean bond length, increased distortion of the B-site, and a slight increase in the average M-M distance. 相似文献
6.
This paper presents new geochemical data on the complex of alkaline metasomatic rocks and carbonatites, which hosts the rare-metal mineralization of the Gremyakha-Vyrmes massif. The contents of major and trace, including rare-earth elements were determined in the albitites, aegirinites, and carbonatites. Two types of the rare-metal ores are distinguished: niobium albitite and zirconium aegirinite ores. It was shown that the albitites and aegirinites have similar trace element distribution patterns, being most geochemically close to the foidolites. The carbonatites, albitites, and aegirinites were dated by Rb-Sr and Sm-Nd methods at 1887 ± 58 Ma, which corresponds to the formation age of the Gremyakha-Vyrmes massif. The ultrabasic rocks, foidolites, alkaline metasomatic rocks, and carbonatites were formed successively within a relatively narrow range. The geological observations and geochemical data led us to conclude that the emplacement of the fluid-saturated carbonatite solutions-melts at the final stages of the massif formation against a background of fault tectonics caused a pervasive metasomatism of the ultrabasic and alkaline rock complexes and, as a result, the formation of the alkaline albitites and aegirinites. The carbonatites could be sources of rare-metals, while foidolites served as a geochemical barrier, and their metasomatic alteration led to the formation of Zr-Nb mineralization in the albitites and aegirinites. 相似文献
7.
A detailed Sr−Nd isotopic study of primary apatite, calcite and dolomite from phoscorites and carbonatites of the Kovdor massif
(380 Ma), Kola peninsula, Russia, reveals a complicated evolutionary history. At least six types of phoscorites and five types
of carbonatite have been identified from Kovdor by previous investigators based on relative ages and their major and accessory
minerals. Isotopic data from apatite define at least two distinct groups of phoscorite and carbonatite. Apatite from the earlier
phoscorites and carbonatites (group 1) are characterized by relatively low 87Sr/ 86Sr (0.70330–0.70349) and 143Nd/ 144Nd initial ratios (0.51230–0.51240) with F=2.01–2.23 wt%, Sr=2185–2975 ppm, Nd=275–660 ppm and Sm=31.7–96.2 ppm. Apatite from
the second group has higher 87Sr/ 86Sr (0.70350–0.70363) and 143Nd/ 144Nd initial ratios (0.51240–0.51247) and higher F (2.63–3.16 wt%), Sr (4790–7500 ppm), Nd (457–1074 ppm) and Sm (68.7–147.6
ppm) contents. This group corresponds to the later phoscorites and carbonatites. One apatite sample from a carbonatite from
the earlier group fits into neither of the two groups and is characterized by the highest initial 87Sr/ 86Sr (0.70385) and lowest 143Nd/ 144Nd (0.51229) of any of the apatites. Within both groups initial 87Sr/ 86Sr and 143Nd/ 144Nd ratios show negative correlations. Strontium isotope data from coexisting calcite and dolomite support the findings from
the apatite study. The Sr and Nd isotopic similarities between carbonatites and phoscorites indicate a genetic relationship
between the two rock types. Wide variations in Sr and Nd isotopic composition within some of the earlier carbonatites indicate
several distinct intrusive phases. Oxygen isotopic data from calcite and dolomite (δ 18O=+7.2 to +7.7‰ SMOW) indicate the absence of any low-temerature secondary processes in phoscorites and carbonatites, and
are consistent with a mantle origin for their parental melts. Apatite data from both groups of phoscorite plot in the depleted
quadrant of an ε Nd versus ε Sr diagram. Data for the earlier group lie along the Kola Carbonatite Line (KCL) as defined by Kramm (1993) and data from the
later group plot above the KCL. The evolution of the phoscorites and carbonatites cannot be explained by simple magmatic differentiation
assuming closed system conditions. The Sr−Nd data can best be explained by the mixing of three components. Two of these are
similar to the end-members that define the Kola Carbonatite Line and these were involved in the genesis of the early phoscorites
and carbonatites. An additional component is needed to explain the isotopic characteristics of the later group. Our study
shows that apatite from rocks of different mineralogy and age is ideal for placing constraints on mantle sources and for monitoring
the Sr−Nd evolution of carbonatites.
Editorial responsibility: W. Schreyer 相似文献
8.
This contribution firstly presents particularities of mineral chemistry of platinum-group elements (PGE) mineralization from
placer deposits linked to the Bor-Uryakh massif of the Maimecha-Kotui Province, northern part of the Siberian Craton. The
chemical composition of PGE mineralization has been studied by electron microprobe analysis. At Bor-Uryakh, main platinum-group
minerals (PGM) comprise Os-Ir and Pt-Fe alloys represented by individual crystals, and polyphase PGM assemblages. The majority
(e.g., 12 out of 19) of the Os-rich nuggets are iridian osmium, with subordinate amounts of native osmium (Os) and chengdeite
(Ir 3Fe). Pt-Fe alloys have a stoichiometric composition close to Pt 2Fe. According to the nomen-clature by L. Cabri and C. Feather [1975] these minerals correspond to ferroan platinum. Based
on geological position and geochemical features of investigated PGE mineralization the particular rock sources have been established.
This study has demonstrated the similarity of chemical characteristics of Os-Ir and Pt-Fe alloys of the Bor-Uryakh massif
to those of PGM from the Guli massif (Maimecha-Kotui Province), platiniferous zoned-type ultramafic massifs (e.g., Kondyor,
Inagli and Chad) of the Aldan Province and Platinum belt of the Urals (Nizhny Tagil, Kytlym, etc.). 相似文献
10.
In order to determine the conditions of mineral formation, a suite of sodalite syenite samples was investigated from the differentiated complex and in part from the eudialyte lujavrite complex of the Lovozero alkaline massif. The compositions of major and accessory minerals were analyzed using an electron microprobe. Various mineral geothermometers ( Bt- Cpx, Amph- Cpx, and Amph- Bt) were applied to estimate the temperature of formation of clinopyroxene-bearing assemblages from the sodalite syenites. The temperature varied from ~990 to 595–630°C, which reflects various stages of crystallization. The temperatures of formation of sodalite assemblages were estimated from the compositions of coexisting sodalite phases as 625–530°C and appeared to be in good agreement with estimates obtained by other mineral geothermometers. Based on the data on the composition and crystallization temperature of sodalites, the minimum concentration of salts (NaCl and Na 2SO 4) in the mineral-forming fluid was estimated as 10–20 wt % NaCl eq. for the two-sodalite assemblages and 1.5–3.0 wt % NaCl eq. for the nosean-bearing assemblages. The molar fraction of sulfur in the fluid was also estimated: 0.02 for the two-sodalite assemblages and 0.04–0.27 for the nosean-bearing assemblages. 相似文献
11.
The present work is a first comprehensive study of the trace-element composition and zoning in clinopyroxene- and amphibole-group minerals from carbonatites, incorporating samples from 14 localities worldwide (Afrikanda, Aley, Alnö, Blue River, Eden Lake, Huayangchuan, Murun, Oka, Ozernaya Varaka, Ozernyi, Paint Lake, Pinghe, Prairie Lake, Turiy Mys). The new electron-microprobe data presented here significantly extend the known compositional range of clinopyroxenes and amphiboles from carbonatites. These data confirm that calcic and sodic clinopyroxenes from carbonatites are not separated by a compositional gap, instead forming an arcuate trend from nearly pure diopside through intermediate aegirine–augite compositions confined to a limited range of CaFeSi 2O 6 contents (15–45 mol%) to aegirine with < 25 mol% of CaMgSi 2O 6 and a negligible proportion of CaFeSi 2O 6. A large set of LA-ICPMS data shows that the clinopyroxenes of different composition are characterized by relatively low levels of Cr, Co and Ni (≤ 40 ppm) and manifold variations in the concentration of trivalent lithophile and some incompatible elements (1–150 ppm Sc, 26–6870 ppm V, 5–550 ppm Sr, 90–2360 ppm Zr, and nil to 150 ppm REE), recorded in some cases within a single crystal. The relative contribution of clinopyroxenes to the whole-rock Rb, Nb, Ta, Th and U budget is negligible. The major-element compositional range of amphiboles spans from alkali- and Al-poor members (tremolite) to Na–Al-rich Mg- or, less commonly, Fe-dominant members (magnesiohastingsite, hastingsite and pargasite), to calcic–sodic, sodic and potassic–sodic compositions intermediate between magnesio-ferrikatophorite, richterite, magnesioriebeckite, ferri-nyböite and (potassic-)magnesio-arfvedsonite. In comparison with the clinopyroxenes, the amphiboles contain similar levels of tetravalent high-field-strength elements (Ti, Zr and Hf) and compatible transition elements (Cr, Co and Ni), but are capable of incorporating much higher concentrations of Sc and incompatible elements (up to 500 ppm Sc, 43 ppm Rb, 1470 ppm Sr, 1230 ppm Ba, 80 ppm Pb, 1070 ppm REE, 140 ppm Y, and 180 ppm Nb). In some carbonatites, amphiboles contribute as much as 25% of the Zr + Hf, 15% of the Sr and 35% of the Rb + Ba whole-rock budget. Both clinopyroxenes and amphiboles may also host a significant share (~ 10%) of the bulk heavy-REE content. Our trace-element data show that the partitioning of REE between clinopyroxene (and, in some samples, amphibole) and the melt is clearly bimodal and requires a revision of the existing models assuming single-site REE partitioning. Clinopyroxenes and amphiboles from carbonatites exhibit a diversity of zoning patterns that cannot be explained exclusively on the basis of crystal chemistry and relative compatibility of different trace-element in these minerals. Paragenetic analysis indicates that in most cases, the observed zoning patterns develop in response to removal of selected trace elements by phases co-precipitating with clinopyroxene and amphibole (especially magnetite, fluorapatite, phlogopite and pyrochlore). With the exception of magnesiohastingsite–richterite sample from Afrikanda, the invariability of trace-element ratios in the majority of zoned clinopyroxene and amphibole crystals implies that fluids are not involved in the development of zoning in these minerals. The implications of the new trace-element data for mineral exploration targeting REE, Nb and other types of carbonatite-hosted rare-metal mineralization are discussed. 相似文献
12.
This paper reports a geochemical and mineralogical study on carbonatites from the Guli massif, which hosts rare-metal mineralization. The principal carriers of radioactive elements in the carbonatites are pyrochlore-group minerals, zirconolite, and thorianite, which are described here. They are characterized by elevated concentrations (wt %) of radioactive elements: up to 17.89 UO 2 and 20.01 ThO 2 in pyrochlore, up to 6.49 UO 2 and 94.29 ThO 2 in thorianite, and up to 6.74 ThO 2 in zirconolite. The pyrochlore-group minerals, zirconolite, and thorianite from the early calcite carbonatites occur in intimate association with Ti-Zr oxides calzirtite, perovskite, and baddeleyite. Significant radioactive element fractionation in early-stage derivatives results in the depletion of the residual magmatic products in these elements. The dolomite carbonatites are reported to contain only trace amounts of pyrochlore-group minerals. It was shown that the distribution of U, Th, Nb, and Ta in the calcite and dolomite carbonatites is correlated with the evolutionary trends of pyrochlore composition. Typical schemes of isomorphic substitution are proposed for pyrochlore-group minerals and zirconolite. The pyrochlore-group minerals show an apparent evolutionary trend from U-rich towards more Th- and Ta-rich varieties, and Ba-Sr cation-deficient varieties originate during the latest stage of the evolution. The pyrochlore-group minerals, zirconolite, and thorianite may also accumulate in placers, together with gold. Because of the relative ease of extraction of the accessory minerals, the carbonatites of the Guli massif can be considered as commercial sources of radioactive raw materials. 相似文献
13.
Summary 32 carbonate samples from a series of metamorphic rocks of greenschist to almandine-amphibolite facies in the Zillerthal Alps were investigated by optical and chemical methods, X-ray diffractometry, and the scanning electron microscope.The carbonates consist mainly of calcite which contains up to 11 mole % (MgCO 3+FeCO 3). Some of the calcites are characterized by skeleton-like dolomitic exsolutions of rhombohedral shape that are orientated on rhombohedron planes of the calcite matrix.The relations between metamorphic grade and calcite composition will be discussed. The (FeCO 3+MgCO 3)-content of calcite depends on the temperature of formation, CO 2 pressure, and the Fe and Mg concentrations of the carbonate-forming solutions.
Mineralogische und chemische Zusammensetzung von Karbonaten aus den Zillertaler Alpen, Tirol (Österreich) Zusammenfassung 32 Karbonatproben aus den Zillertaler Alpen (Tirol, Österreich) wurden mit optischen und röntgendiffraktometrischen Methoden sowie mit dem Elektronenrastermikroskop untersucht.Die Karbonate sind Calcite, die bis zu 11 Mol% (MgCO3+FeCO3) enthalten. Die Calcitkristalle zeichnen sich durch skelettartige Dolomitentmischungen aus, die parallel zu Rhomboederflächen des Calcites orientiert sind.Die Karbonate stammen aus einer Serie metamorpher Gesteine der Grünschiefer- bis Almandin-Amphibolitfazies. Es werden die Beziehungen zwischen der Calcitzusammensetzung und dem Metamorphosegrad diskutiert. Der (FeCO3+MgCO3)-Gehalt der Calcite hängt von der Bildungstemperatur, vom CO2-Druck und vom Fe- und Mg-Gehalt der Lösungen ab, aus denen sich die Karbonate gebildet haben.
With 10 Figures 相似文献
17.
Complex oxides of the pyrochlore (space groups Fd3 m, [8]A 2
[6]B 2O 7) and garnet ( Ia3 d, [8]A 3
[6]B 2
[4]T 3O 12) structures (“A” = Ca 2+, Ln 3+/4+, An 3+/4+; “B” = (Ti, Sn, Hf, and Zr) 4+ in pyrochlore, and Al 3+, Ga 3+, and Fe 3+ in garnet alone; “T” = (Al 3+, Ga 3+, and Fe 3+) are promising matrices for actinide-bearing wastes. In order to identify optimal compositions of these phases, their isomorphic
capacity with respect to REE, actinides, and other components of wastes was examined. The long-term behavior of the matrix
at a repository was predicted based on data obtained on the behavior of pyrochlores and garnets under ion irradiation and
244Cm decay and on the determined leaching rates of REE from the matrices because of their interaction with aqueous solutions,
including that after amorphization. In order to propose efficient synthesis techniques, samples prepared with the use of various
methods were studied. The possibility of incorporating long-lived decay products of 99Tc into the crystalline matrices was analyzed. 相似文献
18.
Summary The eastern part of the agpaitic Khibina complex is characterized by the occurrence of dykes of various alkali silicate rocks and carbonatites. Of these, picrite, monchiquite, nephelinite and phonolite have been studied here. Whole rock and mineral geochemical data indicate that monchiquites evolved from a picritic primary magma by olivine+ magnetite fractionation and subsequent steps involving magma mixing at crustal levels. None of these processes or assimilation/magma mixing of wall rocks or other plutonic rocks within the complex can entirely explain the geochemical and Nd–Sr-isotopic characteristics of the monchiquites (i.e. a covariant alignment between ( 87Sr/ 86Sr) 370=0.70367, ( 143Nd/ 144Nd) 370=0.51237 and ( 87Sr/ 86Sr) 370=0.70400, ( 143Nd/ 144Nd) 370=0.51225 representing the end points of the array). This signature points to isotopic heterogeneities of the mantle source of the dyke-producing magma. The four mantle components (i.e. depleted mantle, lower mantle plume component, EMI-like component and EMII-like component) must occur in different proportions on a small scale in order to explain the isotopic variations of the dyke rocks. The EMII-like component might be incorporated into the source area of the primary magma by carbonatitic fluids involving subducted crustal material. The most likely model to explain the small-scale isotopic heterogeneity is plume activity. The results of this study do not provide any support to a cogenetic origin (e.g. fractionation or liquid immiscibility) for carbonatite and monchiquite or other alkali-silicate dyke rocks occurring in spatial proximity. Instead, we propose that both, carbonatite and picrite/monchiquite, originated by low-degree partial melting of peridotite. Textural observations, mineralogical data, and C and O isotopic compositions suggest incorporation of calcite from carbonatite in monchiquite and the occurrence of late-stage carbothermal fluids.Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1007/s00710-003-0016-2 相似文献
19.
Potassium-rich volcanic rocks in the Isparta area (SW Turkey) consist mainly of older (Pliocene) volcanic rock suites (e.g.,
lamprophyre, basaltic trachyandesite, trachyandesite, trachyte) and younger (Quaternary) caldera forming lava dome/flows (e.g.,
tephriphonolite, trachyte) and pyroclastics (ash/pumice fall deposits and ignimbritic flows). The magnetic susceptibility
( K) was performed for both groups. The magnetic susceptibility value of the less evolved rocks characterized by SiO 2 < 57 wt% (e.g., basaltic trachyandesite, tephriphonolite, lamprophyric rocks) and having mostly mafic phenocrysts such as
pyroxene, amphibole, and biotite-phlogopite is over 10 (10 −3 [SI]). Fine to medium-grained and subhedral to anhedral opaque minerals are scattered especially in the matrix phase of the
less evolved volcanic rocks. However, the K value of the more evolved rocks (e.g., trachyte and trachyandesites) with SiO 2 over 57 wt% vary between 0.1 and 28, but most of them below 10. SI values are negatively correlated with SiO 2, Na 2O, but positively correlated with Fe 2O 3, CaO, MnO, P 2O 5 and MgO contents, suggesting inverse variation of SI with fractionation of potassic magma. That is to say that less evolved
volcanic rocks have relatively higher magnetic susceptibility values in the volcanic suite. Fine to medium-grained and subhedral
to anhedral Fe-Ti oxides are scattered mainly in the matrix phase of the less evolved volcanics, presumably cause the pronounced
relatively higher magnetic susceptibility. 相似文献
20.
A corundum-bearing mafic rock in the Horoman Peridotite Complex, Japan, was derived from upper mantle conditions to lower crustal conditions with surrounding peridotites. The amphiboles found in the rock are classified into 3 types: (1) as interstitial and/or poikilitic grains (Green amphibole), (2) as a constituent mineral of symplectitic mineral aggregates with aluminous spinel at grain boundary between olivine and plagioclase (Symplectite amphibole) and (3) as film-shaped thin grains, usually less than 10 μm in width, at grain boundary between olivine and clinopyroxene (Film-shaped amphibole). The Film-shaped amphibole is rarely associated with orthopyroxene extremely low in Al 2O 3, Cr 2O 3 and CaO (Low-Al OPX). These minerals were formed by infiltration of SiO 2- and volatile-rich fluids along grain boundaries after the rock was recrystallized at olivine-plagioclase stability conditions, i.e. the late stage of the exhumation of the Horoman Complex. Chondrite-normalized rare earth element patterns and primitive mantle-normalized trace-element patterns of the Green amphibole and clinopyroxene are characterized by LREE-depleted patterns with Eu positive and negative anomalies of Zr and Hf. These geochemical characteristics of the constituent minerals were inherited from original whole-rock compositions through a reaction involving both pre-existing clinopyroxene and plagioclase. We propose that the fluids were originally rich in a SiO2 component but depleted in trace-elements. Dehydration of the surrounding metamorphic rocks in the Hidaka metamorphic belt, probably related to intrusion of hot peridotite body into the Hidaka crust, is a plausible origin for the fluids. 相似文献
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