摘要
狼娃山铁矿为矽卡岩型铁矿,位于甘肃省肃北县狼娃山地区,中亚造山带以南,该区地质特征的认识仍不够全面,找矿方向尚未明确。本文基于野外调查及室内测试研究,归纳总结狼娃山铁矿床地质特征,探讨该地区铁矿找矿方向。研究表明:下石炭统白山组下亚组上、下段的流纹质凝灰熔岩为狼娃山铁矿主要含矿层;铁矿石全岩主要化学成分为w(TFe)=38.18%、w(SiO_(2))=21.96%、w(CaO)=7.05%、w(MgO)=6.80%、w(Al_(2)O_(3))=6.14%,约占总量的80%,表明铁、石英、绢云母及碳酸盐岩为其主要构成,属酸性铁矿石;铁矿石物相w(TFe)平均为34.95%,w(mFe)平均为27.18%,mFe占TFe的77.78%,铁矿石主要矿物为磁铁矿(磁铁矿矿石);单矿物磁铁矿、赤铁矿电子探针测试分别属于普通磁铁矿、赤铁矿。铁矿成矿多发育在红石山南华力西期岛弧带,下石炭统白山组安山质熔凝灰岩及英安质凝灰岩控制铁矿产出,矽卡岩化可指示找矿;分析认为,狼娃山矿床深度在400~800 m空间范围内仍存在很大的找矿潜力,可发展为以铁为主的多金属矿床。
Langwashan Fe deposit is a skarn type deposit located in Langwashan area,Subei county,Gansu province in the South of Central Asian orogenic belt.Based on the field investigation and lab research this paper deals with geological characteristics and discusses ore prospecting direction of the deposit.Rhyolitic tuff aceous lava of the upper and lower members of the lower sub-formation of Baishan formation of Lower Carboniferous Series is the main ore-bearing rock.Bulk analysis of the Fe ore is w(TFe)=38.18%,w(SiO_(2))=21.96%,w(CaO)=7.05%,w(MgO)=6.80%,w(Al_(2)O_(3))=6.14%.The four items account for about 80% of the total and suggest that quartz,sericite and carbonate are the main components of the ore and the ore,acidic type.Physical phase analysis is average w(TFe),34.95%,average w(mFe),27.18%,about 77.78% of the TFe,magnetite the main ore mineral(magnetite ore).Electronic probe analysis shows that the magnetite and hematite in the ore are the ordinary ones.The Fe metallogenic process occurs mainly at Hercynian island arc belt in south of Hongshishan mountain.The fused andesitic tuff and dacitic tuff of the Lower Carboniferous Baishan formation controls development of the Fe deposit.Skarnization is the prospecting mark.It is analyzed that Fe ore prospecting is still potential to depth 400-800 m at Langwashan Fe deposit and it will be developed a Fe-dominated polymetallic deposit.
作者
李小罗
LI Xiaoluo(Changsha Engineering and Research Institute Ltd.of Nonferrous Metallurgy,Changsha 410019,China)
出处
《地质找矿论丛》
CAS
2022年第4期295-305,共11页
Contributions to Geology and Mineral Resources Research
关键词
狼娃山铁矿
矽卡岩
成矿物质来源
找矿标志
甘肃北山
Langwashan Fe deposit
skarn
source of ore material
prospecting mark
Baishan area of Gansu province