Next Article in Journal
Mining the Frequent Patterns of Named Entities for Long Document Classification
Next Article in Special Issue
Vanadium and Cobalt Occurrence in the Fe-Ti-V Oxide Deposits Related to Mesoproterozoic AMCG Complex in NE Poland
Previous Article in Journal
Characterization of a Continuous Muon Source for the Non-Destructive and Depth-Selective Elemental Composition Analysis by Muon Induced X- and Gamma-rays
Previous Article in Special Issue
A Fluid Inclusion and Critical/Rare Metal Study of Epithermal Quartz-Stibnite Veins Associated with the Gerakario Porphyry Deposit, Northern Greece
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Applied Sciences
Volume 12
Issue 5
10.3390/app12052542
applsci-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Geology and Petrogeochemistry of Lijiapuzi Nb-Ta Granitic Pegmatite Deposit: Implications for Ore Genesis and Prospecting

by
Jianfei Fu
1,
Yuzeng Yao
1,*,
Jing Liu
1,
Zining Li
1,
Sanshi Jia
2 and
Yemao Pang
3
1
Department of Geology, Northeastern University, Shenyang 110004, China
2
School of Resource and Materials, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
3
No.101 Geology Team Co., Ltd., Liaoning Nonferrous Geology Bureau, Fushun, 113015, China
*
Author to whom correspondence should be addressed.
Appl. Sci. 2022, 12(5), 2542; https://doi.org/10.3390/app12052542
Submission received: 20 December 2021 / Revised: 23 February 2022 / Accepted: 24 February 2022 / Published: 28 February 2022
(This article belongs to the Special Issue Mineralogy of Critical Elements Deposits)
Browse Figures
Versions Notes

Abstract

:
Most of the rare metal pegmatite deposits in China lie in West, Central and South China, and the Lijiapuzi Nb-Ta deposit is the only pegmatite-type Nb-Ta deposit in Northeast China, therefore a detailed study of the Lijiapuzi deposit is of great importance to the metallogeny and exploration of rare metal deposits in Northeast China. The Nb-Ta bearing pegmatites in Lijiapuzi district are composed of a microcline wall zone, a muscovite (lepidolite)-albite intermediate zone and a quartz core, and the rare metal mineralization mainly occurs in the intermediate zone and is intimately related to the albitization. The lithogeochemical features indicate that Lijiapuzi pegmatoids are rich in silicon and alkaline, poor in calcium, magnesium, titanium and phosphorus, and belong to peraluminous granitoid rocks. The enrichment of large ion lithophile elements (LILEs) and depletion of high field-strength elements (HFSEs), the distinct right-inclined REE pattern with obvious Eu negative anomaly, lower ratio of Nb/Ta and higher ratio of La/Nb and Rb/Sr indicate that the pegmatite was of a crustal origin and formed in relatively extensional tectonic setting of post-orogenesis. The pegmatites in Lijiapuzi area can be divided into two categories, i.e., the NW-trending pegmatites are shorter and thicker, with obvious zoning and localized in the upper part of the near-surface, while the NE-trending pegmatites are longer, thinner, devoid of zoning and localized in the lower part of the district. This probably means that excellent ore prospecting potential exists in the lower part of the Lijiapuzi district.

1. Introduction

Rare metals are essential to modern industry, especially high-tech industries such as micro-electronics, specialty alloys and high-strength low-alloys etc., [1,2,3,4], which are regarded as strategic and critical metals [3,4,5,6]; however, their production has long been limited in a few countries, and thus their resources, types of deposit, origin, genesis, and tectonic settings attract attention worldwide [7,8,9,10]. Globally the Ta resources mainly occur in pegmatites and rare element-enriched peraluminous granites [3,4,6]; consequently, pegmatites had long been the foci of metallogenic research.
The inherent coarse-grained and in most cases zoning features make the pegmatites distinct from common rocks with similar composition, resulting in the precise determination of the bulk composition of the entire pegmatite almost impossible [11]. Even a simple classification schedule is difficult for pegmatites, as summarized by some scholars [11,12]. Currently, the five-class depth-zone classification [13] and its revision scheme [14], combined with the family classification [8], are the most widely used for granitic pegmatites. The prominence of the scheme is to introduce the geochemical subdivision of the rare element pegmatite class into three families: the niobium- yttrium-fluorine (NYF) family, the lithium-cesium-tantalum (LCT) family, and the mixed NYF-LCT family. Furthermore the NYF-LCT subdivision has become independent from the depth zone classification and been used to distinguish pegmatites of the other four classes as well [12].
In China, pegmatite deposits are one of the most important rare metal metallogenetic types [15,16,17], e.g., the famous Koktokay pegmatite in Altai [18,19] and the recently discovered Renli high-grade super-large Nb-Ta deposit in Hunan Province [20], indicating a conspicuous mineral resource potential. However, the granitic pegmatoid Nb-Ta deposits discovered so far in China are mainly concentrated in West, Central and South China. The Lijiapuzi Nb-Ta deposit, exploited in the 1970s as a muscovite deposit and confirmed to be a Nb-Ta pegmatite deposit in 2018, is the only pegmatite-type rare metal deposit proven by systematic exploration in Northeast China. Considering that both the Zhaojinggou granitic pegmatite Nb-Ta deposit in Inner Mongolia [21,22] and the Lijiapuzi pegmatite Nb-Ta deposit locate at the northern margin of North China Craton, this probably indicates that there is a large-scale rare element mineralization in this area. From this point of view, the detailed study on the metallogeny of the Lijiapuzi deposit is of great importance to evaluation of the resource potential of rare metals in Northeast China.

2. Geological Setting

North China Craton (NCC), compared to the adjacent Central Asian Orogenic Belt in the north and the Central China Orogenic Belt (Qinling-Dabie Orogenic Belt) in the south, is a relatively stable block (Figure 1). The NCC is composed of a Western Block and an Eastern Block, separated by the north-trending Trans-North China Orogen (TNCO), which developed through a series of subduction-related systems and occurred as the suture zone between the two blocks [23,24]. The TNCO and the marginal zones of NCC reactivated in the late tectonomagmatic activities, especially during the Mesozoic collision between the Pacific Plate and the Eurasian Plate, and resulted in the formation of various mineral deposits, i.e., most of the hydrothermal ore deposits are distributed along TNCO and the marginal zones of the NCC [24,25,26].
The Lijiapuzi Nb-Ta deposit, ca.110 km southeast of Shenyang city (the capital of Liaoning Province), with longitude 124°48′13″ E and latitude 41°27′46″ N, lies in the eastern margin of the NCC. Regionally, the most widely spread strata is Archean high-grade metamorphic rocks of the Anshan group, whose lithology includes plagioclase amphibolites, biotitic granulites, amphibole gneiss, migmatitic granite and banded iron formation. The Sinian shale and limestone are scattered in the south part of the research area. The phanerozoic cover layers are mainly quartz sandstone, limestone, and Mesozoic continental volcano-sedimentary formation such as tuff, shale, and volcanic breccias, which as a whole lies unconformably upon the highly deformed and metamorphosed Archean basement (Figure 1).
Since the formation of the ancient basement rocks, the studying area had experienced multiple periods of magmatism and fracturing, which was beneficial to the migration of hydrothermal fluids and the filling of dykes and veins. Regionally there occur three groups of structures, i.e., the EW trending structures which control the spatial distribution of the Archean basement; the NE- and NW-trending structures are intimately related to the Cambrian and Mesozoic volcanic sedimentary basins [27].
There are two kinds of magmatic rocks in the studying area. One is the Archean anatectic granite; the strong migmatization of volcano-sedimentary rocks was considered to be related to the formation of granitic pegmatites and also to the Nb-Ta mineralization [27]. The other is the intense Mesozoic volcanic-subvolcanic-intrusive rocks, including Jijiapuzi granite, ca.6 km north of the Lijiapuzi deposit with a total exposure area of 120 km2 that has resulted in a more than 100 km2 alteration zone which indicates as pyritization, silification, and epidotization etc. In addition, there was a lot of intermediate to acid dykes such as granite, granitic porphyry, diorite, quartz vein, etc. in the area.

3. Ore Deposit Geology

The lithology that occurred in Lijiapuzi mining district is mainly that of Archean metamorphic rocks and Mesozoic andesite and tuff (Figure 2). The former was metamorphosed so intensely that migmatization occurred widely in the mining area. The Nb-Ta bearing pegmatites were believed to be related to the regional migmatization in the southeastern part of the mining area [27], partially owing to the isotopic dating of muscovite in the pegmatites ranging from 2395 Ma to 2464 Ma (Yonghong Zhang, No. 101 Geological Team Co., Ltd, Liaoning Nonferrous Geology Bureau, Fushun, P. R. China; Unpublished work). The Mesozoic volcanic activities led to the reactivation and superimposition of the brittle fractures upon the ancient basement. The faults in the mining area can be divided into two categories, i.e., the NE trending Lijiapuzi overthrust fault, which dips to the SE with an angle of 40–60°, and the NW trending Dabuqiyan overthrust fault, which dips to the NE with an angle 40–60°. Both the faults are compressive-shearing, conjugated, and belong to the same tectonic stress field.
The detailed exploration of the Lijiapuzi deposit began in 2008 and finished in 2018 [28]. A total of 11 Nb-Ta bearing pegmatites were explored, with an average of 0.0045%Nb2O5 and 0.0312%Ta2O5 (Table 1). Generally the NE-trending pegmatites are longer but thinner, echelon arranged with relatively regular shape such as the vein-type, have large extension depth and weak or no differentiation. The NW-trending pegmatites are shorter but thicker, and usually occur near the surface with small extension depth and relatively irregular shapes such as lenticular and well-differentiated [27]. All the pegmatites are localized in Archean metamorphic rocks. Note that No.1, No.2 and No.9 pegmatite are composed of both the NE-trending and NW-trending sub-fractures, and the pegmatite dikes occur as a whole, indicating that the pegmatite-controlling fractures were formed contemporarily and probably conjugated.
The common differentiation in pegmatites manifests as the microcline wall zone, the albite intermediate zone, and the quartz core whose boundaries are obscure (Figure 3A and Figure 4B). In most cases, the aplite border zone, usually ubiquitous in other rare metal pegmatites [10], is absent in the Lijiapuzi ore district.
In the wall zone, the pegmatite is mainly composed of microcline, quartz and a small amount of garnet, with either a minor amount or no muscovite at all (Figure 3B). In some cases there are quartz-veinlets dispersed in the wall zone, resulting in weak montmorillonitization of the microcline (Figure 4A). In addition, there are few sulfide minerals (Figure 5A,B) ore Nb-Ta minerals. The intermediate zone differs from the wall zone by replacement of the microcline by albite (Figure 3C,D) with irregular boundaries (Figure 4B) and the appearance of massive greenish muscovite (Figure 3E), and occasionally purple lepidolite (Figure 3F), spodumene (Figure 4C), apatite (Figure 4E), and minor beryl, gahnite, cassiterite and zircon [27]. The Nb-Ta minerals such as tantalite and columbite, including microlite [27], were formed along the margin of albite (Figure 5E,F), indicating that the rare metal mineralization was intimately related to the albitization. Locally the mineral grains of early stages such as quartz, microcline, albite and muscovite were fractured and filled by epigenetic hydrothermal minerals. Laser Raman spectroscopy indicates that the opaque minerals involved are needle-like goethite along the cleavage or fractured margin of muscovite (Figure 4D and Figure 5C), accompanied by the accumulation of uranium minerals such as calciouranoite (Figure 5D), which means there should have been an epigenetic hydrothermal mineralization after the formation of the Nb-Ta mineralization [28]. The paragenesis of goethite and uranium minerals is well in accordance with the mineralization pattern of a unconformity-type uranium deposit [29], and so is the Lijiapuzi, which is considered to be of supergene stage [27]. Where the pegmatites become thicker, or locally dilative, for instance, the thicker NW-trending pegmatites with the high differentiation of pegmatite will result in a pure quartz core, with minor or no other minerals (Figure 3G). The miarolitic cavities are seldom seen throughout the mining area.
The wall rock alteration is weak in the Lijiapuzi ore district. Where the pegmatites are thick, especially the flanks around the local dilation parts of the pegmatites, the relatively strong alteration manifests as the chloritization of biotite and hornblende (Figure 3H), and occasionally there occurs some volatile components such as tourmaline in the host rocks (Figure 4F).
Based on the mineral assemblages mentioned above, the pegmatites in Lijiapuzi district belong to the LCT type [13,14].

4. Samples and Methods

The Lijiapuzi pegmatite deposit was first discovered in 1960s and exploited in the 1970s for mica mining. By 2018, a total of 34 boreholes had been drilled, and all the cores had been preserved in the Geological Data Center Co., Ltd., Liaoning Geological Exploration and Mining Group, Shenyang, and core sampling was forbidden. Fortunately, four abandoned mining galleries were left over near the surface (Figure 3A). Twelve rock samples from the local dilation part of No.1 pegmatite were collected from No.2 gallery, among which three were from the wall zone, eight were from the intermediate zone, and one was from the quartz core. All the samples were sliced, part of each sample was sent for the preparation of polished and thin sections, and the other was used for geochemical assay at ALS Chemex (Guangzhou) Co. Ltd.
The bulk chemical compositions were determined by an X-ray fluorescence spectrometer (PANalytical PW2424, Almelo, The Netherlands). The mixture of lithium borate and lithium nitrate were added as melting flux into one piece of rock sample powder, fully mixed and then melted at high temperature. The molten substance was poured into the platinum mold to form a flat slide and then analyzed with an X-ray fluorescence spectrometer. Meanwhile, another piece of powder was put into the muffle furnace and burned at 1000 °C, then cooled and weighed. The weight difference before and after heating is the loss on ignition.
The contents of trace elements and rare earth elements were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). The rock powder was digested with a mixture of perchloric acid, nitric acid, hydrofluoric acid and hydrochloric acid, and diluted with hydrochloric acid and then analyzed by ICP-AES (Agilent 5110, Palo Alto, USA). If the contents of Bi, Hg, Mo, Ag and W were too high, the liquor samples were diluted and analyzed by ICP-MS (Agilent 7900, Palo Alto, USA). After the spectral interference between the elements was corrected, the final result was obtained.

5. Results

The geochemical data, including the contents of major, trace and REE elements of 12 pegmatite samples, are listed in Table 2. The data and their petrogenic significance are summarized as follows.

5.1. The Major Elements

The contents of SiO2 (65.73~88.75%), Na2O (2.19~9.04%), K2O (0.16~10.30%), and Na2O + K2O (3.97~13.67%) are very high, while the contents of CaO (0.10~0.63%), Fe2O3 (0.37~1.18%), MnO (0.01~0.04%), P2O5 (0.03~0.19%) and MgO (0.01~0.13%) is relatively low; the TiO2 content of most samples are lower than the detectable level. The ratios of Al2O3/ (CaO + Na2O + K2O) (A/CNK) range from 1.27 to 6.82, and the ratios of Al2O3/ (Na2O + K2O) (A/NK) are 1.28~6.87, indicating that the Lijiapuzi pegmatites are rich in silicon and alkaline, and poor in calcium, magnesium, titanium, and phosphorus. All the samples fall in the peraluminous range in the A/NK-A/CNK diagram [30] (Figure 6). In the Harker diagram, with the increasing of content of SiO2, the contents of Al2O3 and P2O5 decrease, while Fe2O3 increases (Figure 7). The alkaline components are another situation. Not the content of Na2O or K2O, but the sum of Na2O and K2O manifests excellent linear negative correlation with that of SiO2. Moreover, although the relationship between Na2O and K2O is not obvious, the samples from the wall zone are notably different from those of other zones, which definitely illustrate the albitization of K-feldspar (microcline). The variability of CaO, TiO2 and MgO is not obvious.
Note that the sample of LJP-5 should be the pure quartz core (Figure 3G), but the contents of Al2O3 and Na2O are obviously high. This is probably due to the albite mixed in the sample, and this should not severely disturb the interpretation of trace elements and REEs.

5.2. The Rare Earth Elements

The total contents of rare earth elements in pegmatite range from 4.0 × 10−6 to 3.77 × 10−6 with an average of 5.78 × 10−6, the light rare earth elements (LREEs) contents account for 1.98 × 10−6~12.65 × 10−6 with an average of 5.12 × 10−6, while the heavy rare earth elements (HREEs) contents account for 0.39 × 10−6~1.12 × 10−6, with an average of 0.66 × 10−6; the ratios of LREEs/ HREEs range from 3.14 to 11.5, suggestive of an obvious differentiation between LREEs and HREEs.
The chondrite-normalized rare earth element (REE) diagram exhibits a conspicuous right-inclining tendency with strong Eu negative anomalies (Figure 8); however, a slight “M-type” tetrad effect still can be seen. This means the pegmatites in the Lijiapuzi deposit should have resulted from the high fractional crystallization of magma, and probably experienced strong hydrothermal fluid interaction [31].

5.3. The Trace Elements

The features of trace elements of pegmatites in the Lijiapuzi district are similar. The primitive mantle normalized trace elements spidergram shows that Cs, Rb, K, Sr, LREEs and Ta, Pb, U etc. are enriched, while Zr, Eu, Ti, Sc, Yb are depleted (Figure 8). The sharp Ti depletion indicates that perhaps a crust-derived substance participated in magmatic activity and probably experienced the fractional crystallization of ilmenite. The ratio of Nb/Ta ranges from 0.032 to 13.0, which is much lower than that of primitive mantle and chondrite; this means the parental magma of the pegmatites was probably crust- rather than mantle- derived. The ratio of Rb/Sr ranges from 3.18 to 575.41, which is much higher than that of primitive mantle, which has an average of 0.029, suggesting that the pegmatites resulted from the high differentiation of magma and experienced the fractional crystallization of plagioclase.
The comparation of particular trace elements among various zones is more indicative of the metallogeny. In contrast with the samples of the wall zone, the contents of Cs, U, Th, Be and Sn of the intermediate zone and quartz core significantly increase, which is well in accordance with the mineral assemblages mentioned above. This means that the pegmatites of Lijiapuzi are confirmed to be of the LCT type.
Note that the characteristics of the trace and rare earth elements of samples from three distinct zones are almost the same, which indicates that the features of the elements can be used to the provenance and the tectonic study setting of the pegmatoid rocks in the Lijiapuzi district.

6. Discussion

6.1. Petrogenesis of Pegmatites

Currently, the classification scheme of granite accepted by most scholars is to be I, S, A, and M type [32], and the Amphibole, Cordierite and alkaline mafic minerals are the crucial classification criteria [33]. In the Lijiapuzi mining district, field and microscopic observation indicates that there are minor mafic minerals in pegmatites, and the pegmatites belong to peraluminous rocks in the A/NK-A/CNK diagram (Figure 6). Accordingly, as a result of geochemical assay, the contents of Fe2O3 (0.37~1.18%), MnO (0.01~0.04%) and MgO (0.01~0.13%) in Nb-Ta bearing pegmatites are very low; the content of Ti is lower than the detectable level. This means that the pegmatites belong to a crust-derived, S-type granitoid.
The pegmatites are enriched in LILEs such as Cs, Rb, K and Sr and depleted in HFSEs such as Zr, Ti and Sc (Figure 8). The high ratio of Rb/Sr indicates that there was probably fractional crystallization of plagioclase. The low amount of Yb (0.06~0.12 × 10−6) and Y (0.4~3.0 × 10−6), and the distinct differentiation between LREEs and HREEs with obvious Eu negative anomalies and the right-inclined REE normalized pattern imply that there should be garnet residue in the source magma [34]. The lower ratio of Nb/Ta and the higher ratio of La/Nb and Rb/Sr indicate that the pegmatites in Lijiapuzi should be of upper crustal origin [35,36].
It should be pointed out that the Ti contents of most of the samples in Lijiapuzi district are lower than the detectable level. The sharp Ti depletion probably indicates that rutile remained as a residual phase during the partial melting. It is well known that the cation radii of Nb+5, Ta+5 and Ti+4 are almost the same, as Nb+5 and/or Ta+5 tends to strongly partition into rutile in the crystalline phase [37,38]. Furthermore the rutile incorporates Nb preferentially over Ta, and this explains the enrichment of Ta over Nb in highly fractionated granitic rocks [39] and also the pegmatoid rocks in the Lijiapuzi deposit.

6.2. Tectonic Setting

Granitoid rocks can be used to discriminate the petrogenetic tectonic setting [8,40,41,42], and some scholars have strongly advocated a classification scheme of Nb-Ta bearing pegmatites by their tectonic setting to better understand the granitic pegmatite deposits [43]. In other words, the tectonic setting is of great importance to the metallogeny of ore deposits.
In the Y vs. Nb diagram, all of the pegmatitic rocks fall in the volcanic arc and syn-collision granite zone, in the Nb + Y vs. Rb diagram they mostly fall in the syn-collision granite zone with two rocks on the boundary line between sys-collision and volcanic arc granite zone, i.e., the pegmatite should be formed in the synorogenic tectonic setting. In the Yb vs. Ta diagram, most rocks fall in syn-collision granite zone, with two in the within-plate-granites zone, however, in the Yb + Ta vs. Rb diagram, rocks falling in the syn-collision granites zone and the within-plate granite zone are almost the same (Figure 9).
NCC, where the Liijiapuzi ore deposit is located, is a relatively stable block. The ancient Archean basic volcano-sedimentary strata experienced intense regional metamorphism and migmatism. As for the eastern Liaoning area, the thickest central part of the Proterozoic Liaohe group occurred as a result of there being intensely metamorphic volcanic rocks at the bottom and slightly metamorphic sedimentary rocks at the top. The unique lithologic sequences earned the name of “Liaodong rift” [44], whose forming mechanism is still controversial, as there is some question as to whether it resulted from the continental rift [45,46] or as the result of a modern plate collision [47,48,49]. However, there seems to be a consensus that the eastern Liaoning area was under the extensional tectonic setting in the paleo-Proterozoic era. The Lijiapuzi pegmatites clearly occurred as dikes and lens, indicating a relatively extensional environment. In summary, the Lijiapuzi Nb-Ta deposit was formed in a relatively extensional environment of the post-orogenic stage.

6.3. Nb-Ta Mineralization in Lijiapuzi Pegmatite Deposit

The Nb-Ta mineralization of pegmatite has long been disputed by many scholars worldwide. Magmatic crystallization differentiation was firstly promoted as the main rare-metal mineralization mechanism [50,51,52], but later many scholars found that the post-magmatic hydrothermal fluids and the late-stage metasomatism play an important role in the mineralization [53,54]. Currently, both of the mechanisms are advocated by most geologists [55,56,57], especially the post-magmatic supercritical fluid [58,59] and the albitization [56,57].
Field truth and microscopic observation indicate that the Lijiapuzi pegmatites exhibit obvious albitization of microcline and late-stage uranium mineralization superimposition. The Nb-Ta mineralization is intimately related to the albite metasomatism of the intermediate muscovite (lepidolite) -albite zone. The features of major components and trace elements indicate that the Lijiapuzi pegmatite was of crust-derived origin, and the residual rutile fractionated the Nb and Ta in the peraluminous granitic melts and formed in a relatively extensional environment of the post-orogenic tectonic setting, i.e., the Lijiapuzi Nb-Ta deposit was formed by the albitization processes of pegmatite in a post- orogenic collision setting in the eastern margin of NCC was and superimposed by a slightly late-stage uranium mineralization.

6.4. Implications for Nb-Ta Mineral Resource Potential in Lijiapuzi District

As mentioned above, the popular classification scheme of grantic pegmatites today gradually turns from the inferred depth-zone dependent criterion to the measurable CMS (Chemical composition—Mineral assemblage—Structural geology) criterion, with emphasis on the practical application [11,12]. However, no one unique classification scheme can include all of the pegmatiod rocks up to now [11].
Beskin and Marin discovered in their research on rare metal mineralization in Eastern Transbaikalia that the LCT pegmatites should further be divided into two types: a “multicomponent rare metal type” and an “albite-spodumene pegmatite” [60,61]. The former occurs as a large crystal with obvious zoning, of a relatively small scale and is usually localized in the upper part of the region, while the latter manifests as multiple extended dikes with no zoning, huge length, and usually locates in the underlying part of the former. Actually the long dikes are not pegmatite but granites serving as the “parent magma” of the multicomponent rare metal. These two kinds of pegmatoid rocks were rare metal mineralized. From this point of view, the classification is surely indicative of ore prospecting.
The NW-trending pegmatites in Lijiapuzi are shorter, thicker, obvious-zoning and localized in the upper part of the near-surface, while the NE-trending pegmatites are longer, thinner, devoid of zoning and localized in the lower part of the district. This probably means that there is excellent ore prospecting potential in the lower part of the Lijiapuzi district.

7. Conclusions

(1)
The Nb-Ta bearing pegmatites in Lijiapuzi are mainly composed of coarse-grained microcline, albite, muscovite, lepidolite, quartz, spodumene, and apatite, with minor beryl, gahnite, cassiterite and zircon and fine-grained tantalite, columbite, microlite, goethite and uranium minerals. The rare metal bearing pegmatites belong to the LCT-type deposit. The Nb-Ta mineralization mainly occurred in the process of albitization in the intermediate zone, and was superimposed by a late-stage uranium mineralization.
(2)
The lithogeochemical features indicate that Lijiapuzi pegmatoids are rich in silicon and alkaline, poor in calcium, magnesium, titanium, and phosphorus, and belong to peraluminous granitoid rocks. The enrichment of LILEs and the depletion of HFSEs, the distinct right-inclined REE pattern with obvious Eu negative anomaly, lower ratio of Nb/Ta and higher ratio of La/Nb and Rb/Sr indicate that the pegmatites were of a crustal origin and formed in relatively extensional tectonic setting of post-orogenesis.
(3)
There are two kinds of pegmatites in the Lijiapuzi district, i.e., the NW-trending pegmatites, which are shorter, thicker, obvious-zoning and localized in the upper part of the near-surface, and the NE-trending pegmatites are longer, thinner, devoid of zoning and are localized in the lower part of the district. This probably means that there is excellent ore prospecting potential in the lower part of the Lijiapuzi district.

Author Contributions

Writing—original draft preparation, J.F.; writing—review and editing, Y.Y.; visualization, J.L.; data curation, Z.L.; investigation, S.J. and Y.P. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the National Key Research and Development Program of China (grant number: 2017YFC1503105).

Acknowledgments

The authors were deeply indebted to Yonghong Zhang, the director of No.101 Geology Team Co., Ltd., Liaoning Nonferrous Geology Bureau, for his kind help in field investigation. The authors are very grateful to three anonymous reviewers for their constructive comments that greatly help us to improve the original version of the manuscript.

Conflicts of Interest

The authors declare that they have no conflicts of interest.

References

  1. Linnen, R.L.; Van Lichtervelde, M.; Černý, P. Granitic pegmatites as sources of strategic metals. Elements 2012, 8, 275–280. [Google Scholar] [CrossRef]
  2. London, D. Ore-forming processes within granitic pegmatites. Ore Geol. Rev. 2018, 101, 349–383. [Google Scholar] [CrossRef]
  3. Mackay, D.A.R.; Simandl, G.J. Geology, market and supply chain of niobium and tantalum—A review. Miner. Depos. 2014, 49, 1025–1047. [Google Scholar] [CrossRef]
  4. Linnen, R.; Trueman, D.; Burt, R. Tantalum and niobium. In Critical Metal Handbook; Gunn, G., Ed.; John Wiley & Sons, Ltd.: West Sussex, UK, 2014; pp. 361–384. [Google Scholar]
  5. Krishnamurthy, P. Rare metal and rare earth element resources: World scenario with special reference to India. J. Geol. Soc. India 2020, 95, 465–474. [Google Scholar] [CrossRef]
  6. Simandl, G.J.; Burt, R.O.; Trueman, D.L.; Paradis, S. Economic geology models 4. Tantalum and niobium: Deposits, resources, exploration methods and market—A primer for geoscientists. Geosci. Can. 2018, 45, 85–96. [Google Scholar] [CrossRef] [Green Version]
  7. Simmons, W.B.; Webber, K.L. Pegmatite genesis: State of the art. Eur. J. Mineral. 2008, 20, 421–438. [Google Scholar] [CrossRef]
  8. Černy, P. Rare-element granitic pegmatite. Part II: Regional to global environments and pretrogenesis. Geosci. Can. 1991, 18, 68–81. [Google Scholar]
  9. Landes, K.K. Origin and classification of pegmatites. Am. Miner. 1933, 18, 33–56. [Google Scholar]
  10. London, D. Pegmatites; The Canadian Mineralogist, Special Publication 10; Mineralogical Association of Canada: Quebec City, QC, Canada, 2008; pp. 1–308. [Google Scholar]
  11. Dill, H.G. The CMS classification scheme (Chemical composition—Mineral assemblage—Structural geology)—linking geology to mineralogy of pegmatitic and aplitic rocks. J. Min. Geochem. 2016, 193, 231–263. [Google Scholar] [CrossRef]
  12. Müller, A.; Simmons, W.; Beurlen, H.; Thomas, R.; Ihlen, P.M.; Wise, M.; Roda-Robles, E.; Neiva, A.M.R.; Zagorsky, V. A proposed new mineralogical classification system for granitic pegmatites-Part I: History and the need for a new classification. Can. Mineral. 2018, 56, 1–25. [Google Scholar]
  13. Černy, P. Rare-element granitic pegmatite. Part I: Anatomy and internal evolution of pegmatite deposits. Geosci. Can. 1991, 18, 49–67. [Google Scholar]
  14. Černy, P.; Ercit, T.S. The classification of granitic pegmatites revisited. Can. Mineral. 2005, 43, 2005–2026. [Google Scholar] [CrossRef] [Green Version]
  15. Li, J.K.; Li, P.; Wang, D.H. A review of niobium and tantalum metallogenic regularity in China. Chin. Sci. Bull. 2019, 64, 1545–1566. [Google Scholar] [CrossRef]
  16. Wang, R.C.; Che, X.D.; Wu, B. Critical mineral resources of Nb, Ta, Zr, and Hf in China. Chin. Sci. Bull. 2020, 65, 3763–3777. [Google Scholar] [CrossRef]
  17. Zhang, L.; Lin, D.S. Current situation of rare metal resources in China. Geol. Prosp. 2004, 40, 26–30. [Google Scholar]
  18. Zhu, J.C.; Wu, C.N.; Liu, C.S.; Li, F.C.; Huang, X.L.; Zhou, D.S. Magmatic-hydrothermal evolution and genesis of Koktokay No.3 rare metal pegmatite dyke, Altai, China. Geol. J. China Univ. 2000, 6, 40–51. [Google Scholar]
  19. Zhou, Q.F.; Qin, K.Z.; Tang, D.M.; Ding, J.G.; Guo, Z.L. Mineralogy and significance of micas and feldspars from the Koktokay No. 3 pegmatitic rare-element deposit, Altai. Acta Petrol. Sin. 2013, 29, 3004–3022. [Google Scholar]
  20. Liu, X.; Zhou, F.C.; Huang, Z.B.; Li, J.K.; Zhou, H.X.; Xiao, G.Q.; Bao, Y.H.; Li, P.; Tan, L.M.; Shi, W.K.; et al. Discovery of Renli Superlarge pegmatite-type Nb-Ta polymetallic deposit in Pingjiang, Hunan Province and its significances. Geotecton. Metallog. 2018, 42, 235–243. [Google Scholar]
  21. Gao, Y.; Sun, Y.; Zhao, Z.; Li, J.K.; He, H.H.; Yang, Y.Q. 40Ar-39Ar dating of muscovite from the Zhaojinggou Nb-Ta polymetallic deposit in Wuchuan county of Inner Mongolia and its geological implications. Rock Mineral. Anal. 2017, 36, 551–558. [Google Scholar]
  22. Li, Z.D.; Li, X.G.; Cui, Y.R.; Li, G.Z.; Zhang, J.; Guo, H.; Liu, W.G.; Zhang, C.; Yu, R.G.; Xie, Y.; et al. Yanshanian mineralization of Zhaojinggou Nb-Ta deposit, Inner Mongolia: Evidences from the monazite and zircon LA-MC-ICP-MS U-Pb and biotite 40Ar- 39Ar geochronology. Earth Sci. 2019, 4, 234–247. [Google Scholar]
  23. Zhao, G.C.; Cawood, P.A.; Wilde, S.A.; Sun, M.; Lu, L.Z. Metamorphism of basement rocks in the Central Zone of the North China Craton: Implications for Paleoproterozoic tectonic evolution. Precam. Res. 2000, 103, 55–88. [Google Scholar] [CrossRef]
  24. Pirajno, F. The Geology and Tectonic Settings of China’s Mineral Deposits; Springer: Berlin/Heidelberg, Germany, 2013; pp. 35–118. [Google Scholar]
  25. Li, S.R.; Santosh, M. Metallogeny and craton destruction: Record from the North China Craton. Ore Geol. Rev. 2014, 56, 376–414. [Google Scholar] [CrossRef]
  26. Zhu, R.X.; Fan, H.R.; Li, J.W.; Meng, Q.R.; Li, S.R.; Zeng, Q.D. Decratonic gold deposits. Sci. China Earth Sci. 2015, 58, 1253–1537. [Google Scholar] [CrossRef]
  27. Diao, C.C.; Feng, J.L.; Yu, J.H.; Zhu, X.Z. Geological characteristics of the Lijiapuzi niobium-tantalum deposit in Xinbin County, Liaoning Province. Geol. Res. 2013, 22, 20–24. [Google Scholar]
  28. Pang, Y.M. Metallogenic Regularity of Lijiapuzi Nb-Ta Deposit, Xinbin, Liaoning Province. Master’s Thesis, Northeastern University, Shenyang, China, June 2021. [Google Scholar]
  29. Pirajno, F. Hydrothermal Processes and Mineral Systems; Springer: Dordrecht, The Netherlands, 2009; pp. 1213–1241. [Google Scholar]
  30. Maniar, P.D.; Piccoli, P.M. Tectonic discrimination of granitoids. Geol. Soc. Amer. Bull. 1989, 101, 635–643. [Google Scholar] [CrossRef]
  31. Wu, F.Y.; Jahn, B.M.; Wilde, S.A.; Lo, C.H.; Yui, T.F.; Lin, Q.; Ge, W.C.; Sun, D.Y. Highly fractionated I-type granites in NE China (I): Geochronology and petrogenesis. Lithos 2003, 66, 241–273. [Google Scholar] [CrossRef]
  32. Bonin, B. A-type granites and related rocks: Evolution of a concept, prospects. Lithos 2007, 97, 1–29. [Google Scholar] [CrossRef]
  33. Miller, C.F. Are strongly petaluminous magmas derived from politic sedimentary sources? J. Geol. 1985, 93, 673–689. [Google Scholar] [CrossRef]
  34. Defant, M.J.; Xu, J.F.; Kepezhinskas, P. Adakites: Some variations on a theme. Acta Petrol. Sin. 2002, 18, 129–142. [Google Scholar]
  35. Taylor, S.R.; Mclennan, S.M. The geochemical evolution of the continental crust. Rev. Geophys. 1995, 33, 241–265. [Google Scholar] [CrossRef]
  36. Mcdonough, W.F. Compositional model for the earth’s core. In Treatise on Geochemistry; Davis, M.A., Ed.; Elsevier: Amsterdam, The Netherlands, 2013; Volume 2, pp. 547–568. [Google Scholar]
  37. Horng, W.S.; Hess, P.C.; Gan, H. The interactions between M+5 cations (Nb+5, Ta+5, or P+5) and anhydrous haplogranite melts. Geochim. Cosmochim. Acta 1999, 63, 2419–2428. [Google Scholar] [CrossRef]
  38. Xiong, X.L.; Adam, J.; Green, T.H. Rutile stability and rutile/melt HFSE partitioning during partial melting of hydrous basalt: Implications for TTG genesis. Chem. Geol. 2005, 218, 339–359. [Google Scholar] [CrossRef]
  39. Linnen, R.L.; Keppler, H. Columbite solubility in granitic melts: Consequences for the enrichment and fractionation of Nb and Ta in the Earth’s crust. Contrib. Mineral. Petrol. 1997, 128, 213–227. [Google Scholar] [CrossRef]
  40. Pearce, J.A.; Harris, N.G.W.; Tindle, A.G. Trace element discrimination diagrams for the tectonic interpretation of granitic rocks. J. Pet. 1984, 25, 956–983. [Google Scholar] [CrossRef] [Green Version]
  41. Whalen, J.B.; Currie, K.L.; Chappell, B.W. A-type granites: Geochemical characteristics, discrimination and petrogenesis. Contrib. Mineral. Petrol. 1987, 95, 407–419. [Google Scholar] [CrossRef]
  42. Chappell, B.W.; White, A.J.R. I- and S-type granites in the Lachlan Fold Belt. Trans. Royal Soc. Edinb. Earth Sci. 1992, 83, 1–26. [Google Scholar] [CrossRef]
  43. Hou, J.L. The Comparative Study of Diagenetic, Metallogenic Characteristics and Tectonic Environment of Two Kinds of Pegmatites in China. Ph.D. Thesis, Chinese Academy of Geological Sciences, Beijing, China, May 2018. [Google Scholar]
  44. Chen, R.D. A paleo-Proterozoic rift basin: Liaodong rift. Liaoning Geol. 1984, 2, 126–133. [Google Scholar]
  45. Chen, R.D. Geological tectonic evolution of Liaodong rift. Reg. Geol. China 1990, 4, 306–315. [Google Scholar]
  46. Chen, R.D.; Li, X.D.; Zhang, F.S. Several problems about the paleo-Proterozoic geology of eastern Liaodong. Geol. China 2003, 30, 207–213. [Google Scholar]
  47. Wan, Y.S.; Song, B.; Yang, C.; Liu, D.Y. Zircon SHRIMP U-Pb geochronogy of Archean rocks from the Fushun-Qingyuan area, Liaoning Province and its geological significance. ACTA Geol. Sin. 2005, 79, 78–86. [Google Scholar]
  48. Dong, C.Y.; Ma, M.Z.; Liu, S.J.; Xie, H.Q.; Liu, D.Y.; Li, X.M.; Wan, Y.S. Middle Paleoproterozoic crustal extensional regime in the North China Craton: New evidence from SHRIMP zircon U-Pb dating and whole-rock geochemistry of metagabbro in the Anshan- Gongchangling area. Acta Petrol. Sin. 2012, 28, 2785–2792. [Google Scholar]
  49. Bi, J.H.; Xing, D.H.; Ge, W.C.; Yang, H.; Dong, Y. Age and tectonic setting of meta-acid volcanic rocks from the North Liaohe Group in the Liaodong area: Paleoproterozoic intracontinental rift or active continental margin? Earth Sci. Front. 2018, 25, 295–308. [Google Scholar]
  50. Cuney, M.; Marignac, C.; Weisbrod, A. The Besuvoir topaz-lepidolite albite granite (Massif Central, France): The disseminated magrnatic Sn-Li-Ta-Nb-Be mineralization. Econ. Geol. 1992, 87, 1766–1794. [Google Scholar] [CrossRef]
  51. Raimbault, L.; Cuney, M.; Azeacott, C.; Duthou, J.L.; Joron, J.L. Geochemical evidence for a multistage magmatic genesis of Ta-Sn-Li mineralization in the granite at Beauvoir, French Massif Central. Econ. Geol. 1995, 90, 548–576. [Google Scholar] [CrossRef]
  52. Zhu, J.C.; Li, R.K.; Li, F.C.; Xiong, X.L.; Zhou, F.Y.; Huang, X.L. Topaz-albite granites and rare-metal mineralization in the Limu district, Guangxi Province, southeast China. Miner. Depos. 2001, 36, 393–405. [Google Scholar] [CrossRef]
  53. Kempe, U.; Gotze, J.; Dandar, S.; Habermlann, D. Magmatic and metasomatic processes during formation of the Nb-Zr-REE deposits Khaldzan Buregtz and Tsakhir (Mongolian Altai): Indications from a combined CL-SEM study. Mineral. Mag. 1999, 63, 165–177. [Google Scholar] [CrossRef]
  54. Salvi, S.; Williams-Jones, A.E. Alteration, HFSE mineralization and hydrocarbon formation in peralkaline igneous systems: Insights from the Strange Lake Pluton, Canada. Lithos 2006, 91, 19–34. [Google Scholar] [CrossRef]
  55. Wang, F.L.; Zhao, T.P.; Chen, W. Advances in study of Nb-Ta ore deposits in Panxi area and tentative discussion on genesis of these ore deposits. Miner. Depos. 2012, 31, 293–308. [Google Scholar]
  56. Huang, X.E.; Xu, Z.H. Metasomatism and its relationship to rare metal mineralization of Yashan granite, Jiangshan. Jiangxi Nonferrous Met. 2005, 8, 1–4. [Google Scholar]
  57. Wang, Y.R.; Li, J.T.; Lu, J.L.; Fan, W.L. Geochemical mechanism of Nb-Ta mineralization during the late stage of granite crystallization. Geochem 1982, 1, 175–185. [Google Scholar]
  58. Qiu, R.Z.; Zhou, S.; Chang, H.L.; Du, S.H.; Peng, S.B. Role of the supercritical fluid in the process of granitic rock-forming and mineralization: Taking the granitic Nb-Ta deposit in Xianghualing area as an example. Geol. Sci. Technol. Info. 1998, 17, 40–44. [Google Scholar]
  59. Qiu, R.Z.; Peng, S.B.; Du, S.H. Genesis of granitic Nb-Ta deposit in Xianghualing area and the role of the supercritical fluid in the process of rock-forming and mineralization. Hunan Geol. 1997, 16, 92–97. [Google Scholar]
  60. Beskin, S.M.; Marin, Y.B. Classification of granitic pegmatites and pegmatite-bearing granitic systems. Geol. Ore Depos. 2018, 60, 578–586. [Google Scholar] [CrossRef]
  61. Beskin, S.M.; Marin, Y.B. Granite systems with rare-metal pegmatites. Geol. Ore Depos. 2020, 62, 554–563. [Google Scholar] [CrossRef]
Applsci 12 02542 g001 550
Figure 1. Regional geologic map of Lijiapuzi. Ar-Archean metamorphic rocks; Mγ-Archean migmatitic granite; Z-Sinian shale and limestone; ∈-bitumen bearing shale and limestone; O-dolomitic limestone; C-carbonaceous shale; P-quartz sandstone; K-sandstone interlayer with andesite; Q-quaternary.
Figure 1. Regional geologic map of Lijiapuzi. Ar-Archean metamorphic rocks; Mγ-Archean migmatitic granite; Z-Sinian shale and limestone; ∈-bitumen bearing shale and limestone; O-dolomitic limestone; C-carbonaceous shale; P-quartz sandstone; K-sandstone interlayer with andesite; Q-quaternary.
Applsci 12 02542 g001
Applsci 12 02542 g002 550
Figure 2. Geological map of Lijiapuzi Nb-Ta deposit. Lithology is the same as Figure 1B. 1-mineralization borehole; 2-non-mineralization borehole; 3-pegmatite ore bodies; 4-sections.
Figure 2. Geological map of Lijiapuzi Nb-Ta deposit. Lithology is the same as Figure 1B. 1-mineralization borehole; 2-non-mineralization borehole; 3-pegmatite ore bodies; 4-sections.
Applsci 12 02542 g002
Applsci 12 02542 g003 550
Figure 3. Field occurrence of pegmatites in the Lijiapuzi Nb-Ta ore deposit. (A) An abandoned mining gallery; (B) Marginal microcline rock sample, with late quartz veinlets filled in the fractures; (C,D) Transitional albite rock sample, with gradual or irregular boundary; (E) Sample close to quartz core, with greenish muscovite; (F) purple lepidolite; (G) quartz core; (H) Chloritized plagioclase amphibolite; Mcl-microcline; Q-quartz; Ab-albite; Ms-muscovite; Lpd-lepidolite.
Figure 3. Field occurrence of pegmatites in the Lijiapuzi Nb-Ta ore deposit. (A) An abandoned mining gallery; (B) Marginal microcline rock sample, with late quartz veinlets filled in the fractures; (C,D) Transitional albite rock sample, with gradual or irregular boundary; (E) Sample close to quartz core, with greenish muscovite; (F) purple lepidolite; (G) quartz core; (H) Chloritized plagioclase amphibolite; Mcl-microcline; Q-quartz; Ab-albite; Ms-muscovite; Lpd-lepidolite.
Applsci 12 02542 g003
Applsci 12 02542 g004 550
Figure 4. The main minerals in the Lijiapuzi pegmatite deposit (Transmitted cross-polarized light). (A) microcline with crossed twinning, with weak alteration; (B) albitization of microcline with an irregular contact boundary between them; (C) spodumene; (D) muscovite, fractured perpendicular to cleavages and filled by late metallic minerals; (E) apatite; (F) chloritization of plagioclase amphibolites; Mcl-microcline; Ab-albite; Q-quartz; Spd-spodumene; Ms-muscovite; Apt-apatite; Chl-chlorite; Tour-tourmaline.
Figure 4. The main minerals in the Lijiapuzi pegmatite deposit (Transmitted cross-polarized light). (A) microcline with crossed twinning, with weak alteration; (B) albitization of microcline with an irregular contact boundary between them; (C) spodumene; (D) muscovite, fractured perpendicular to cleavages and filled by late metallic minerals; (E) apatite; (F) chloritization of plagioclase amphibolites; Mcl-microcline; Ab-albite; Q-quartz; Spd-spodumene; Ms-muscovite; Apt-apatite; Chl-chlorite; Tour-tourmaline.
Applsci 12 02542 g004
Applsci 12 02542 g005 550
Figure 5. The major metallic minerals in the Lijiapuzi ore deposit. (A) Disseminated granular pyrite; (B) Paragenesis of chalcopyrite and pyrite; (C) Euhedral needle goethite along the cleavage and margin of muscovite, tantalite occurs as enclaves of quartz; (D) Cleavage of muscovite is metasomatized and filled with calciouranoite minerals; (E,F) ColumbiteMn distribute along the margin of albite; Py-pyrite; Cp-chalcopyrite; Ms-muscovite; Tn-tantalite; Gth-goethite; Ccr-calciouranoite; ColMn-columbiteMn; Q-quartz. Notes: (A–D) are under reflected light; (E,F) are identically the same image, E is under transmitted cross-polarized light while F is under reflected light.
Figure 5. The major metallic minerals in the Lijiapuzi ore deposit. (A) Disseminated granular pyrite; (B) Paragenesis of chalcopyrite and pyrite; (C) Euhedral needle goethite along the cleavage and margin of muscovite, tantalite occurs as enclaves of quartz; (D) Cleavage of muscovite is metasomatized and filled with calciouranoite minerals; (E,F) ColumbiteMn distribute along the margin of albite; Py-pyrite; Cp-chalcopyrite; Ms-muscovite; Tn-tantalite; Gth-goethite; Ccr-calciouranoite; ColMn-columbiteMn; Q-quartz. Notes: (A–D) are under reflected light; (E,F) are identically the same image, E is under transmitted cross-polarized light while F is under reflected light.
Applsci 12 02542 g005
Applsci 12 02542 g006 550
Figure 6. The A/CNK-A/NK discriminant diagram for Lijiapuzi pegmatite.
Figure 6. The A/CNK-A/NK discriminant diagram for Lijiapuzi pegmatite.
Applsci 12 02542 g006
Applsci 12 02542 g007a 550Applsci 12 02542 g007b 550
Figure 7. Harker diagram for the pegmatites in Lijiapuzi deposit. Symbols are the same as Figure 6. A-The contents of Al2O3 decrease with the increasing of SiO2 contents; B- The contents of P2O5 decrease with the increasing of SiO2 contents; C- The contents of Fe2O3 slightly increase with the increasing of SiO2 contents; D/E-The contents of K2O or Na2O show no obvious relationship to those of SiO2; F-The sums of K2O and Na2O decrease with the increasing of SiO2 contents.
Figure 7. Harker diagram for the pegmatites in Lijiapuzi deposit. Symbols are the same as Figure 6. A-The contents of Al2O3 decrease with the increasing of SiO2 contents; B- The contents of P2O5 decrease with the increasing of SiO2 contents; C- The contents of Fe2O3 slightly increase with the increasing of SiO2 contents; D/E-The contents of K2O or Na2O show no obvious relationship to those of SiO2; F-The sums of K2O and Na2O decrease with the increasing of SiO2 contents.
Applsci 12 02542 g007aApplsci 12 02542 g007b
Applsci 12 02542 g008 550
Figure 8. (Left) Chondrite normalized REE pattern; (Right) Primitive mantle normalized trace elements spidergram; Symbols are the same as Figure 6.
Figure 8. (Left) Chondrite normalized REE pattern; (Right) Primitive mantle normalized trace elements spidergram; Symbols are the same as Figure 6.
Applsci 12 02542 g008
Applsci 12 02542 g009 550
Figure 9. Tectonic discriminant diagrams of WPG and syn-GOLG suites of the Kenticha granite-pegmatite; Symbols are the same as Figure 6. A-All the rock samples fall in volcanic arc and syn-collision granites domain; B-Most of the rock samples fall in syn-collision granites domain; C-Most of the rock samples fall in syn-collision granites domain; D-Parts of the rock samples fall in syn-collision granites domain, while others fall in within-plate granites domain except for one outlier. The combination of the four subfigures indicates that the pegmatites in Lijiapuzi should be related to orogenesis.
Figure 9. Tectonic discriminant diagrams of WPG and syn-GOLG suites of the Kenticha granite-pegmatite; Symbols are the same as Figure 6. A-All the rock samples fall in volcanic arc and syn-collision granites domain; B-Most of the rock samples fall in syn-collision granites domain; C-Most of the rock samples fall in syn-collision granites domain; D-Parts of the rock samples fall in syn-collision granites domain, while others fall in within-plate granites domain except for one outlier. The combination of the four subfigures indicates that the pegmatites in Lijiapuzi should be related to orogenesis.
Applsci 12 02542 g009
Table
Table 1. The general characteristics of Nb-Ta bearing pegmatites in Lijiapuzi deposit (Adapted from ref. [28]).
Table 1. The general characteristics of Nb-Ta bearing pegmatites in Lijiapuzi deposit (Adapted from ref. [28]).
Ore BodyOre Body SizeGrade (%)Occurrence
Length (m)Average Thickness (m)Nb2O5Ta2O5Dip DirectionDip Angle
①2380.830.00380.0339305°75°
②1560.990.00400.0319315°75°
②-11631.990.00740.0330315°65°
③900.120.00280.0320325°85°
④6481.210.00510.0298145°75°
⑤423.390.00220.051055°40°
⑥261.870.00350.047540°50°
⑦1120.370.00200.015840°65°
⑧1000.280.00200.0592295°40°
⑨310.990.00360.054925°75°
⑩350.270.00200.025470°55°
⑪1020.500.00330.0351302°65°
Table
Table 2. Major, trace and REE data for pegmatite in the Lijiapuzi ore deposit.
Table 2. Major, trace and REE data for pegmatite in the Lijiapuzi ore deposit.
SampleLJP-1LJP-2LJP-3LJP-4LJP-5LJP-6LJP-7LJP-8LJP-9LJP-10LJP-11LJP-12
Wall ZoneCore Intermediate Zone
Major elements (wt%)
SiO268.7771.8465.7376.6075.1477.4588.7575.8281.0381.5671.3372.95
Al2O316.7014.6618.3014.0414.8813.706.7314.6411.3610.8817.4416.44
TFe2O30.410.400.370.531.130.650.510.851.120.831.180.53
Na2O2.732.193.376.884.776.163.725.963.204.056.809.04
K2O9.979.2510.301.211.930.890.251.261.671.121.950.16
CaO0.160.110.220.180.170.250.140.200.100.230.220.63
MgO0.010.030.020.030.130.070.020.060.070.080.060.02
MnO0.010.010.010.010.020.010.020.020.020.020.040.03
Cr2O30.010.010.020.020.020.010.010.010.030.010.010.01
P2O50.140.140.190.110.050.050.070.050.040.030.120.07
BaO0.040.030.030.010.010.010.010.010.010.010.010.01
SrO0.020.020.020.010.010.010.010.010.010.010.010.01
V2O50.010.010.020.020.010.010.010.020.020.010.010.02
LOI0.290.380.400.321.180.490.110.650.880.680.980.14
Total99.2799.0899.0099.9799.4599.76100.3699.5699.5699.52100.16100.06
Trace elements (ppm)
Cs130184.5130.521.568.531.85.4547.696.132.6235.64
Rb837089409410115534201520198.52360351017101660125
Ba252125.5199.534.822.810.215.511.97.713.657.915
Th0.230.610.230.080.40.43.460.162.941.180.120.26
U0.660.680.370.050.530.844.190.250.63.880.091.45
K9.979.2510.31.211.930.890.251.261.671.121.950.16
Nb1.51.522.627.216.720.517.219.560.03.99.8
Ta25.246.441.815.411211660684.912228214.674.2
La1.40.91.10.60.71.231.20.90.71.80.8
Ce1.921.713.42.16.32.31.42.44.11.9
Pb7.49.15.11.12.42.54.31.71.83.41.42.4
Pr0.20.130.180.070.170.270.610.310.150.190.430.15
Sr28.919.62412.66.41112.513.16.111.713.939.3
Nd0.70.440.70.20.612.21.10.60.81.70.5
Zr4.03.03.02.02.02.05.02.02.08.02.02.0
Hf0.20.20.20.20.20.20.70.20.31.00.20.2
Sm0.20.140.210.080.160.210.490.250.190.270.470.16
Eu0.030.030.030.030.030.030.050.040.030.030.050.03
Gd0.210.110.210.120.150.190.430.240.180.430.460.17
Tb0.020.020.030.020.020.030.060.030.030.060.060.02
Dy0.090.10.150.090.110.150.280.160.170.360.270.1
Ti0.010.010.010.010.030.010.010.010.010.020.010.01
Y0.70.50.70.40.50.81.91.00.93.01.60.8
Ho0.020.020.030.020.020.030.050.030.030.080.040.02
Er0.060.060.070.060.060.070.140.070.070.210.090.06
Tm0.010.010.010.010.010.010.020.010.010.030.010.01
Yb0.060.060.060.060.060.060.120.060.060.20.060.07
Lu2.01.72.45.755.425.23.738.232.132.313.04.8
Sc0.10.10.10.10.70.30.10.40.30.80.20.2
Be3.043.244.988.476.557.3216.708.136.966.957.4742.0
Sn0.80.30.727.41.112.51.016.914.921.43.21.2
Eu/Eu *0.34 0.34 0.34 0.34 0.34 0.34 0.57 0.46 0.34 0.34 0.57 0.34
Nb/Ta0.060.030.050.170.240.140.030.200.160.210.270.13
Rare earth elements (ppm)
La1.40.91.10.60.71.23.01.20.90.71.80.8
Ce1.92.01.71.03.42.16.32.31.42.44.11.9
Pr0.20.130.180.070.170.270.610.310.150.190.430.15
Nd0.70.440.70.20.61.02.21.10.60.81.70.5
Sm0.20.140.210.080.160.210.490.250.190.270.470.16
Eu0.030.030.030.030.030.030.050.040.030.030.050.03
Gd0.210.110.210.120.150.190.430.240.180.430.460.17
Tb0.020.020.030.020.020.030.060.030.030.060.060.02
Dy0.090.10.150.090.110.150.280.160.170.360.270.1
Ho0.020.020.030.020.020.030.050.030.030.080.040.02
Er0.060.060.070.060.060.070.140.070.070.210.090.06
Tm0.010.010.010.010.010.010.020.010.010.030.010.01
Yb0.060.060.060.060.060.060.120.060.060.20.060.07
Lu0.010.010.010.010.010.010.020.010.010.030.010.01
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Share and Cite

MDPI and ACS Style

Fu, J.; Yao, Y.; Liu, J.; Li, Z.; Jia, S.; Pang, Y. Geology and Petrogeochemistry of Lijiapuzi Nb-Ta Granitic Pegmatite Deposit: Implications for Ore Genesis and Prospecting. Appl. Sci. 2022, 12, 2542. https://doi.org/10.3390/app12052542

AMA Style

Fu J, Yao Y, Liu J, Li Z, Jia S, Pang Y. Geology and Petrogeochemistry of Lijiapuzi Nb-Ta Granitic Pegmatite Deposit: Implications for Ore Genesis and Prospecting. Applied Sciences. 2022; 12(5):2542. https://doi.org/10.3390/app12052542

Chicago/Turabian Style

Fu, Jianfei, Yuzeng Yao, Jing Liu, Zining Li, Sanshi Jia, and Yemao Pang. 2022. "Geology and Petrogeochemistry of Lijiapuzi Nb-Ta Granitic Pegmatite Deposit: Implications for Ore Genesis and Prospecting" Applied Sciences 12, no. 5: 2542. https://doi.org/10.3390/app12052542

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop