摘要
在广东长坑金银矿床的主要含金岩石碳质硅质岩中两次找到放射虫化石,其时代可能属于早石炭世。在这些碳质硅质岩中还发现一些生物化石残迹,如石英环、石英圈、石英单晶球、石英多晶球、生物残体和似生物结构。由此认为碳质硅质岩原来含有一定量的微体生物化石,形成于海盆环境,应属沉积成因,这是证明碳质硅质岩属于热水沉积成因而不属于热液蚀变交代成因的有力证据;也表明热水沉积过程有生物物质的加入,热水沉积和生物沉积可以混合发生,说明长坑金银矿床形成于张性、不补偿、水较深的盆地之中。对长坑金银矿床的矿区含矿地层应该归属的岩石地层单位提出了疑问。
Some radiolarian fossils were discovered two times in the carbonaceous silicalites, the major gold-bearing rocks in the Changkeng gold-silver deposit. The geologic period of the fossils may belong to Early Carboniferous epoch. Meanwhile, some biological remains were also found in this kind of rocks, such as quartz ring, quartz loop, quartz monocrystal sphere, quartz polycrystal sphere, biological relic and homologous organic texture. Based on these facts, it is considered that these carbonaceous silicalites contained some microbiofossils formerly, generated in sea basin and belong to sedimentary origin. They are strong evidences to prove that the carbonaceous silicalites derived from sedimentary exhalation, and not from hydrothermal alteration-metasomatism. Besides, these facts indicate that some biological material joined in the sedimentary exhalation course, and sedimentary exhalation and organosedimentation could mix each other at a place. They also show that the Changkeng deposit was formed in an extensional, starved and relatively deep-water basin. Finally, a doubt is put forward that whether the lithostratigraphic unit of the strata in Changkeng area is right or not.
出处
《现代地质》
CAS
CSCD
2004年第1期80-88,共9页
Geoscience
基金
中国科学院黄金科技工作领导小组办公室黄金科技项目(KY85-12
KZ951-A1-404-01-04)
广东省自然科学基金项目(940730
990523)
国家攀登计划项目(PD-A-30-06)。
关键词
金矿床
硅质岩
放射虫
化石
生物
长坑
广东
gold deposit
silicalite
radiolaria
fossil
organism
Changkeng
Guangdong
