The Hardat Tolgoi Pb-Zn Deposit, located in the assembly belt of the North China Plate and the Siberia Plate, is a new medium-sized Pb-Zn deposit in the Erenhot-Dongwuqi polymetallic ore belt. Based on the field exploration, study of fluid inclusion, and H, O, S and Pb isotopic compositions, this paper discussed the fluid evolution and metallogenic mechanism of the ore deposit. Fluid inclusions study suggests that the mineralization homogenization temperature ranges from 195℃ to 408℃ with an average of 332.5℃, the salinity from 1.40% to 11.93% NaCleq. with an average of 4.87%NaCleq., and the density 0.61 g/cm3 to 0.89 g/cm3 with an average of 0.72 g/cm3. The histogram diagram shows two peak values, one ranging from 230℃ to 250℃ may be related with metallogenisis; the other from 350℃ to 370℃ may represent the early metallogenic fluid temperatrue. It was estimated that fluid formed under the pressure of about 13.0 MPa and the depth of about 1.3 km. Test results of the Laser Raman analyses indicate that the ore forming fluids belonged to the H2O-NaCl system with little CO2. The study of hydrogen and oxygen compositions indicates that the ore-forming fluid of the Hardat Tolgoi Pb-Zn deposit mainly derived from magmatic water mixed with meteoric water. S and Pb isotopic compositions of the ores are characterized by narrow change range and relatively homogeneity, with δ34S of 4.0‰ to 6.1‰; 206Pb/204Pb of 18.311 to 18.467, 207Pb/204Pb of 15.590 to 15.636, 208Pb/204Pb of 38.253 to 38.393. Both the S and Pb isotopic compositions of ore indicate that the metallogenic materal were derived from magma. All of this suggest that the Hardat Tolgoi Pb-Zn deposit is a shallow mesothermal deposit.

三明地区位于闽西北隆起带与闽西南坳陷带接合部,萤石矿资源丰富,其成矿受常口-瀚仙-余朋北东向断裂构造带控制.总结该断裂构造带地质条件,阐述已知萤石矿点基本特征及找矿标志,通过成矿预测,提出了清流余朋等五个成矿重点区,宜作为今后工作的重点.

Located in the Nanping-Ninghua tectono-magmatic belt,the Gaiyang Group is composed of a low-grade metavolcanic series,which is divided into the Louqian Formation,Sanxizhai Formation and Longtou Formation by Huang Quan-zhen et al.,and its age is assigned to the late Sinian.Through1:50000detailed regional geological survey and reconstruction of the old volcanic structure,the Gaiyang Group is considered to be the product of volcanic activity in the same structural setting according to the stratigraphic sequence,rock association and volcanism.From the early stage to late stage,the rocks make up a complete volcanic-sedimentary cycle from strong to weak eruption.So the authors suggest that the Gaiyang Group may be divided into the Louqian Formation and Longtou Formation,and according to new isotopic data,the ages of the Louqian Formation and Longtou Formation should be assigned to the Nanhua period and Sinian period respectively.

明溪盖洋地区广泛发育的震旦纪火山岩,均已遭受区域变质.前人多数是从变质岩角度对其作研究,笔者是从火山岩及火山作用角度,在调研变质火山岩岩石宏观与微观特征的同时,着重调查古火山构造,研究不同火山产物空间分布特征,寻找残存的古火山构造形迹,并结合遥感资料信息,初步恢复古火山中心.为研究这一时期火山活动特点乃至南平-宁化构造-岩浆带的演化及古构造环境提供了新的资料.

根据电子探针分析成果并结合矿物光性特征,在洋源南部万全岩群中浅变质岩中新发现蓝闪石类矿物--镁钠闪石.它产于闽西北与闽西南两大构造单元交接部位之南平一宁化构造岩浆岩带上,它的出现与四堡期一晋宁期构造作用密切相关,镁钠闪石的发现对于探讨该地区乃至福建大地构造演化,具有一定意义.

福建明溪北部寒塘地区出露一套低绿片岩相浅变质岩系,原划分为中一上元古界下峰(岩)组.经1 : 5万区调和剖面研究,现已查明其空间层位在万全(岩)群之上,并伏于盖洋群之下,其岩石组合、原岩建造与其上覆及下伏岩石地层差异明显,具自身特点,厚度较大,且区内有一定延伸性.因此,作者新创建寒塘组.据其与上覆、下伏地层关系及已取得的930 Ma单颗粒锆石U-Pb同位素年龄资料,将其时代归属青白口纪.该岩石地层单位的建立及其时代确定,对闽西北前寒武纪变质岩地层划分、区域对比及构造研究具有重要意义.