甘肃省金昌市赤霞山稀土矿床地质特征及找矿标志

Geological Characteristics and Prospecting Indicator of Chixiashan REE Deposit in Jinchang, Gansu Province

甘肃省金昌市赤霞山稀土矿赋存于古元古代肉红色粗粒碱长花岗岩中,含矿岩体呈脉状侵入太古宇-古元古界龙首山岩群三岩组。区内圈定稀土矿(化)体10条,伴生钍矿,稀土矿体长60 m~170 m,厚1.41 m~4.06 m, REO平均品位主要为0.59%~3.70%,最高7.35%,稀土类型为轻稀土,主要元素为La、Ce、Pr、Nd。含矿岩石为龙首山岩群重熔后结晶分异形成的肉红色粗粒碱长花岗岩,为成熟度较低的S型花岗岩,矿床类型为花岗岩型稀土矿床。通过对赤霞山稀土矿床地质特征分析,提出了找矿标志,为该地区寻找同类型矿床提供了依据。

The Chixiashan REE deposit in Jinchang, Gansu Province, occurred in the Paleoproterozoic red coarse-grained alkali feldspar granite, the ore-bearing rocks intruded into the third formation of Archean Paleoproterozoic Longshoushan group in form of veins. There are 10 REE ore(mineralized) bodies in this area, associated with thorium ores, the length of REE ore body is 60 m~170 m, and the thickness is 1.41 m~4.06 m.The average grade of REO is mostly 0.59%~3.70%, and the highest is 7.35%.The type of REE belongs to light REE type, and the main elements are La, Ce, Pr and Nd. The ore-bearing rock is the red coarse-grained alkali feldspar granite formed by crystallization differentiation after remelting of Longshoushan group, which is a low maturity S-type granite.The deposit type belongs to granite type rare earth deposit. Based on the analysis of the geological characteristics of the Chixiashan REE deposit, the prospecting criteria are put forward, which provides the basis for searching for the same type of deposits in this area.