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.
Highlights
Rare metals are essential to modern industry, especially high-tech industries such as micro-electronics, specialty alloys and high-strength low-alloys etc., [1–4], which are regarded as strategic and critical metals [3–6]; their production has long been limited in a few countries, and their resources, types of deposit, origin, genesis, and tectonic settings attract attention worldwide [7–10]
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 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]
Summary
Rare metals are essential to modern industry, especially high-tech industries such as micro-electronics, specialty alloys and high-strength low-alloys etc., [1–4], which are regarded as strategic and critical metals [3–6]; their production has long been limited in a few countries, and their resources, types of deposit, origin, genesis, and tectonic settings attract attention worldwide [7–10]. 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
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
