沉积与特提斯地质
沉積與特提斯地質
침적여특제사지질
SEDIMENTARY GEOLOGY AND TETHYAN GEOLOGY
2013年
4期
16-21
,共6页
董黎阳%王剑%尹福光%王鹏%周业鑫
董黎暘%王劍%尹福光%王鵬%週業鑫
동려양%왕검%윤복광%왕붕%주업흠
扬子西缘%北衙组%潮坪%风暴沉积
颺子西緣%北衙組%潮坪%風暴沉積
양자서연%북아조%조평%풍폭침적
western Yangtze block%Beiya Formation%tidal flat%storm deposits
在滇西北衙地区中三叠统北衙组中首次发现风暴沉积,其表现为砾屑灰岩、网纹状灰岩的频繁互层,见丰富的风暴沉积构造。通过对笔架山及倒流箐剖面详细的野外观察及室内分析,识别出4种类型的风暴沉积序列。研究区风暴沉积的背景沉积为薄层网纹状灰岩,发育波状层理、鸟眼等构造,指示潮坪环境。潮坪风暴沉积在研究区的首次发现,对区内中三叠世古地理、古气候的研究具有重要的意义。
在滇西北衙地區中三疊統北衙組中首次髮現風暴沉積,其錶現為礫屑灰巖、網紋狀灰巖的頻繁互層,見豐富的風暴沉積構造。通過對筆架山及倒流箐剖麵詳細的野外觀察及室內分析,識彆齣4種類型的風暴沉積序列。研究區風暴沉積的揹景沉積為薄層網紋狀灰巖,髮育波狀層理、鳥眼等構造,指示潮坪環境。潮坪風暴沉積在研究區的首次髮現,對區內中三疊世古地理、古氣候的研究具有重要的意義。
재전서북아지구중삼첩통북아조중수차발현풍폭침적,기표현위력설회암、망문상회암적빈번호층,견봉부적풍폭침적구조。통과대필가산급도류정부면상세적야외관찰급실내분석,식별출4충류형적풍폭침적서렬。연구구풍폭침적적배경침적위박층망문상회암,발육파상층리、조안등구조,지시조평배경。조평풍폭침적재연구구적수차발현,대구내중삼첩세고지리、고기후적연구구유중요적의의。
The storm deposits are recognized for the first time from the Middle Triassic Beiya Formation in the Beiya region, western Yunnan, and consist of alternating gravelly limestones and reticulated limestones with abundant sedimentary structures of storm deposits such as erosional soles, lag deposits, graded beddings and hummocky cross-beddings. The background deposits of the storm deposits are dominated by thin-bedded reticulated limestones with wavy beddings and bird’ s-eye structures, suggesting a tidal-flat environment in the study area. The discovery of the tidal-flat storm deposits may be important to the research of the palaeogeography and palaeoclimatology in the study area during the Middle Triassic.