【摘要】 <正> 小寺沟岩浆活动主要发生在燕山运动晚期。三次岩浆侵入,形成了下杖子二长斑岩、上杖子花岗闪长斑岩和晚期脉岩(主要是闪长玢岩、花岗斑岩)。这三种岩石都含有引人注目的钾长石巨斑。在含钼(铜)矿化的花岗闪长斑岩体中,这种巨斑普遍发育,但展布很不均匀,一般聚集于岩体的顶部、边部。为了弄清这种钾长石巨斑的特征以及与成岩成矿的关系,笔者作了如下工作:更多还原

【Abstract】 In the Mo-bearing intrusion of He Bei province, K-feldspar phanerocrysts possess the character of large size (the largest 7× 5.1 × 0.38cm3), better crystal shape and close relation to hydrothermal and structural activity. Inside the phanerocrysts there are residues of plagioclase, quartz, boitite and groundmass. X-diffraction and infrared spectrometer analyses show that most part of K-feldspar phanerocrysts are in middle order, and belong to ortholase series. The inclusion filling temperature of the phanerocrysts is below 400°G. Therefore. K-feldspar phanerocrysts in the intrusion is considered to be products of hydrothermal of early potassium alteration of mineralized rock body.更多还原