中国地质
中國地質
중국지질
CHINESE GEOLOGY
2015年
2期
641-654
,共14页
铝土矿含矿岩系%石炭系%海相微体生物%陆相沉积%海相沉积%黔中-渝南
鋁土礦含礦巖繫%石炭繫%海相微體生物%陸相沉積%海相沉積%黔中-渝南
려토광함광암계%석탄계%해상미체생물%륙상침적%해상침적%검중-투남
bauxite-bearing rock series%Carboniferous%marine microfossils%continental deposition%marine deposition%central Guizhou-southern Chongqing area
黔中—渝南地区于紫云运动初期的泥盆纪末已准平原化,在石炭纪铝土矿含矿岩系沉积过程中,含矿岩系下段(铁质?粘土岩段)主要为近海湖泊相,含矿岩系上段(铝质岩段)为近海平原相。在这种大环境前提下,经常会受到海泛与强风暴潮的影响与改造,使得主要是陆相环境沉积形成的铝土矿含矿岩系中,含有少量海相大化石(腕足类)和微体生物化石(疑源类和牙形石);另在下段和上段岩矿层间,时夹海相碳酸盐岩透镜体,具明显海相沉积特征。以上表明,黔中—渝南石炭系铝土矿含矿岩系形成环境具有显著的多样性和复杂性,而非单纯的陆相沉积环境所能概括的。
黔中—渝南地區于紫雲運動初期的泥盆紀末已準平原化,在石炭紀鋁土礦含礦巖繫沉積過程中,含礦巖繫下段(鐵質?粘土巖段)主要為近海湖泊相,含礦巖繫上段(鋁質巖段)為近海平原相。在這種大環境前提下,經常會受到海汎與彊風暴潮的影響與改造,使得主要是陸相環境沉積形成的鋁土礦含礦巖繫中,含有少量海相大化石(腕足類)和微體生物化石(疑源類和牙形石);另在下段和上段巖礦層間,時夾海相碳痠鹽巖透鏡體,具明顯海相沉積特徵。以上錶明,黔中—渝南石炭繫鋁土礦含礦巖繫形成環境具有顯著的多樣性和複雜性,而非單純的陸相沉積環境所能概括的。
검중—투남지구우자운운동초기적니분기말이준평원화,재석탄기려토광함광암계침적과정중,함광암계하단(철질?점토암단)주요위근해호박상,함광암계상단(려질암단)위근해평원상。재저충대배경전제하,경상회수도해범여강풍폭조적영향여개조,사득주요시륙상배경침적형성적려토광함광암계중,함유소량해상대화석(완족류)화미체생물화석(의원류화아형석);령재하단화상단암광층간,시협해상탄산염암투경체,구명현해상침적특정。이상표명,검중—투남석탄계려토광함광암계형성배경구유현저적다양성화복잡성,이비단순적륙상침적배경소능개괄적。
The central Guizhou-southern Chongqing area had experienced peneplanation at the beginning of Ziyun Movement before the end of the Devonian. In the deposition process of the Carboniferous bauxite-bearing rock series, the lower bauxite-bearing rock series (iron-clay rock) was mostly offshore lake facies, and the upper bauxite-bearing rock series (aluminous rock) was mostly offshore plain facies. In this environment, the influence and reformation of ingression and strong storm surge were frequent. Thus, there exsited a few marine plant fossils (brachiopoda) and marine microfossils (acritarch and conodont) in the bauxite-bearing rock series, which mostly deposited in a continental environment. And there were less marine carbonate lens in the lower (iron-clay rock segment) and the upper (aluminiferous rock segment) bauxite-bearing rock series, suggesting obvious characteristics of marine deposition. All these phenomena indicate that the formation environment of the bauxite-bearing rock series in central Guizhou-southern Chongqing area was very diverse and complex. It was affected not only by continental sedimentary environment but also by other factors.