地质通报
地質通報
지질통보
GEOLOGICAL BULLETIN OF CHINA
2015年
1期
113-120
,共8页
李朝柱%王书兵%傅建利%蒋复初
李朝柱%王書兵%傅建利%蔣複初
리조주%왕서병%부건리%장복초
金沙江%龙街粉砂层%上更新统%新构造
金沙江%龍街粉砂層%上更新統%新構造
금사강%룡가분사층%상경신통%신구조
Jinsha River%Longjie silt layer%Late Pleistocene%neotectonics
沿金沙江攀枝花三堆子至武定县白马口段河谷两岸分布一套以灰黑色、灰黄色、灰白色粉砂、粘土质粉砂和粘土为主的湖相地层,尤以云南省元谋县龙街盆地内最为发育,被称为龙街粉砂层。通过龙街YA钻孔和龙街、白泥湾剖面的磁性地层学和光释光年代学的研究,探讨龙街粉砂层的时代与归属。龙街YA钻孔地层厚度101.18m,其中龙街粉砂层厚92.96m,上覆7.5m的红棕色细砂和砂砾石层,下伏厚度大于0.72m的灰绿色含角砾粗砂。综合分析YA钻孔的磁性地层学和光释光年龄,认为获取龙街粉砂层的沉积时代为150~30ka BP,属于晚更新世。通过地层沉积特征变化,反演晚更新世以来湖泊的形成及沉积环境变化,探讨晚更新世以来区域新构造的活动阶段及其对河流演化过程的控制作用。
沿金沙江攀枝花三堆子至武定縣白馬口段河穀兩岸分佈一套以灰黑色、灰黃色、灰白色粉砂、粘土質粉砂和粘土為主的湖相地層,尤以雲南省元謀縣龍街盆地內最為髮育,被稱為龍街粉砂層。通過龍街YA鑽孔和龍街、白泥灣剖麵的磁性地層學和光釋光年代學的研究,探討龍街粉砂層的時代與歸屬。龍街YA鑽孔地層厚度101.18m,其中龍街粉砂層厚92.96m,上覆7.5m的紅棕色細砂和砂礫石層,下伏厚度大于0.72m的灰綠色含角礫粗砂。綜閤分析YA鑽孔的磁性地層學和光釋光年齡,認為穫取龍街粉砂層的沉積時代為150~30ka BP,屬于晚更新世。通過地層沉積特徵變化,反縯晚更新世以來湖泊的形成及沉積環境變化,探討晚更新世以來區域新構造的活動階段及其對河流縯化過程的控製作用。
연금사강반지화삼퇴자지무정현백마구단하곡량안분포일투이회흑색、회황색、회백색분사、점토질분사화점토위주적호상지층,우이운남성원모현룡가분지내최위발육,피칭위룡가분사층。통과룡가YA찬공화룡가、백니만부면적자성지층학화광석광년대학적연구,탐토룡가분사층적시대여귀속。룡가YA찬공지층후도101.18m,기중룡가분사층후92.96m,상복7.5m적홍종색세사화사력석층,하복후도대우0.72m적회록색함각력조사。종합분석YA찬공적자성지층학화광석광년령,인위획취룡가분사층적침적시대위150~30ka BP,속우만경신세。통과지층침적특정변화,반연만경신세이래호박적형성급침적배경변화,탐토만경신세이래구역신구조적활동계단급기대하류연화과정적공제작용。
The Longjie silt layer consists of a series of silt, silty clay and clay lacustrine sediments which are grayish black, grayish yel?low and grayish white in color. This silt layer is distributed along the valley of the Jinsha River from Sanduizi of Panzhihua City to Baimakou of Wuding County, and is well developed in the Longjie basin in Yunnan Province. The Longjie drill hole intersects the stratatigraphic thickness of 101.18m, which includes 92.96m Longjie silt layer. Its sedimentation occurred about 150~30ka BP, as shown by the analysis of magnetostratigraphy and OSL dating. Through the study of sedimentary variation characteristics, this paper deals with the formation process of Longjie silt layer, the relative regional neotectonics movement stage and its influence on the devel?opment of the Jinsha River.