CAJ | 학술논문

塔中隆起区上奥陶统良里塔格组灰岩与桑塔木组砂-粉砂岩之间为不整合接触,昭示着这两个组沉积期之间存在一次历时约百万年的区域性构造抬升事件.中古31井良里塔格组三段的4 125.6～4 133.9 m井段为垮塌型溶洞沉积,洞顶距良里塔格组二段顶部190.6 m,溶洞中角砾状充填物主要来自良里塔格组洞壁本身的礁相灰岩,且见数厘米厚的暗河流水沉积纹层,未发现源于其它时代的颗粒混杂其间.这一事实指证了溶洞的形成和充填时代均为良里塔格组沉积之后、桑塔木组覆盖之前的晚奥陶世凯迪中期.具溶蚀力的淡水潜流带的深度一般不低于周围的海平面,由此可推断出该井区这次抬升出海平面之上的高度,即使忽略良里塔格组顶部可能经地表剥蚀的良里塔格组一段,抬升出水面部分至少也应该有190 m,藉生态地层学恢复洞壁礁灰岩沉积时的海水深度约为30 m±,因此总抬升幅度至少能达到220 m.
탑중륭기구상오도통량리탑격조회암여상탑목조사-분사암지간위불정합접촉,소시착저량개조침적기지간존재일차력시약백만년적구역성구조태승사건.중고31정량리탑격조삼단적4 125.6～4 133.9 m정단위과탑형용동침적,동정거량리탑격조이단정부190.6 m,용동중각력상충전물주요래자량리탑격조동벽본신적초상회암,차견수전미후적암하류수침적문층,미발현원우기타시대적과립혼잡기간.저일사실지증료용동적형성화충전시대균위량리탑격조침적지후、상탑목조복개지전적만오도세개적중기.구용식력적담수잠류대적심도일반불저우주위적해평면,유차가추단출해정구저차태승출해평면지상적고도,즉사홀략량리탑격조정부가능경지표박식적량리탑격조일단,태승출수면부분지소야응해유190 m,자생태지층학회복동벽초회암침적시적해수심도약위30 m±,인차총태승폭도지소능체도220 m.
Unconformably contact between the sandstone-siltstone of the Sangtamu Formation and limestone of the Lianglitag Formation in Ordovician,Kaitian,exists in the Tazhong High,central Tarim Platform. It distinctively indicates a regional tectonic uplift event happened with duration of about 1 Ma. A suite of coalesced,collapsed-paleocave sediment occurred from the 4 125.6～4 133.9 m drilling core of the well Zhonggu 31 is assigned to the Member 3 of the Lianglitag Formation. The depth between the cave-ceiling and the top of the Lianglitag Formation is about 190 m. The sediment-fill facies mainly consist of chaotic breccias sourced from the cave-wall,which the latter had been reefal rocks originally. Centimeters thick of laminated silciclastic debris implicates hidden river facies. Sediment of no-Kaitian time has not been found. Such a case implies that the formed and filled-processions of the paleocave was consistent to the time-interval between the post-Lianglitag Formation and pre-Sangtamu Formation timely. The depth of the vadose with dissolutional excavation was generally not lower than its surrounding sea-level. Even though the un-remained thickness of the Member 1 of the Lianglitag Formation,which had been eroded by karstfication of the earth surface in advance of a new cycle transgression of the Sangtamu Formation could be negative,the exposed part of the Lianglitag Formation above the sea-level was minimal of 190 m at least. Reefal rocks of the cave-wall were formed at a depth about 30 m of the sea-floor. Thus,the sum of the exposed high plus the reef community depth results the amplitude of the uplift.