CAJ | 학술논문

基于地震、钻井及露头资料的综合分析，对川东南-黔北志留系石牛栏组及同期异相的小河坝组沉积与层序地层进行了研究。结果表明：①石牛栏组与下伏龙马溪组共同构成一个独立的三级层序，石牛栏组为高位体系域的一部分；②石牛栏组内部呈现为两个次一级的海平面升降旋回，可进一步划分为上、下两个四级层序；③台地边缘礁滩相在两个四级层序的高位体系域中均有一至两期小规模的发育，但在上部四级层序中最发育；④石牛栏组沉积期表现为台缘缓坡模式，因为台缘到斜坡没有明显坡折，加上陆源碎屑的影响，导致生物礁发育规模普遍很小，多呈点状或串珠状分布；⑤研究区内石牛栏组白云岩化作用总体上很弱，推测该时期海水盐度较低，主要由两个原因所致，一是来自南边黔中隆起及东边雪峰隆起的淡水河流注入导致研究区内海水盐度较低，二是台地边缘礁滩隆起幅度较低，无法形成相对局限的高盐度环境；⑥南川一带的小河坝组应当属于低河流能量、欠充沛物源且以悬浮搬运为主的低建设性浅水三角洲。
기우지진、찬정급로두자료적종합분석，대천동남-검북지류계석우란조급동기이상적소하패조침적여층서지층진행료연구。결과표명：①석우란조여하복룡마계조공동구성일개독립적삼급층서，석우란조위고위체계역적일부분；②석우란조내부정현위량개차일급적해평면승강선회，가진일보화분위상、하량개사급층서；③태지변연초탄상재량개사급층서적고위체계역중균유일지량기소규모적발육，단재상부사급층서중최발육；④석우란조침적기표현위태연완파모식，인위태연도사파몰유명현파절，가상륙원쇄설적영향，도치생물초발육규모보편흔소，다정점상혹천주상분포；⑤연구구내석우란조백운암화작용총체상흔약，추측해시기해수염도교저，주요유량개원인소치，일시래자남변검중륭기급동변설봉륭기적담수하류주입도치연구구내해수염도교저，이시태지변연초탄륭기폭도교저，무법형성상대국한적고염도배경；⑥남천일대적소하패조응당속우저하류능량、흠충패물원차이현부반운위주적저건설성천수삼각주。
Based on the integrated analysis of seismic ,drilling and outcrop data ,this paper studied the deposition and se-quence stratigraphy characteristics of Shiniulan & Xiaoheba formations in southeastern Sichuan -northern Guizhou pro-vinces.The following results were obtained .The Shiniulan Fm and its underlying Longmaxi Formation compose a separate third-order sequence ,and the Shiniulan Formation is part of a high-stand system tract .There are two sub-eustatic sea le-vel cycles in the Shiniulan Formation ,so this formation can be further divided into an upper and a lower fourth-order se-quence .There are one to two development phases of platform margin reef&bank facies in the high-stand system tract of each fourth-order sequence ,but the best platform reef&bank facies lies in the upper one .The bioherms developed during the deposition of the Shiniulan Formation are generally small and in scattered or beaded distribution due to the non -exis-tence of obvious slope break between platform margin and slope as well as the dilution of terrigenous inputs .In the study area,the dolomitization of the Shiniulan Fm is very weak as a whole .It is assumed that the salinity was low in this stage mainly due to factors .The first is the input of fresh water from the central Guizhou Uplift in the south and Xuefeng Uplift in the east.The second is the low amplitude of uplift of platform margin reef&bank .The sedimentary environment of the Xiaoheba Formation in Nanchuan area should be a shallow water constructive delta with low river energy ,non-well deve-loped provenance and predominant suspension transport .