CAJ | 학술논문

识别海相碳酸盐岩台地深部的成盐聚钾层段，主要依靠测井解译和钻井取芯验证。连续沉积的碳酸盐岩台地具有旋回性，记录着海相碳酸盐岩随古海平面旋回变化的信息。因此，利用测井数据模拟台地高频沉积旋回叠加样式，反演古海平面旋回，寻找海退地层序列的低水位沉积体系，进而快速锁定成盐聚钾层段的方法值得探索。文中以四川盆地川中广安地区三叠系为例，以等间距连续测量的自然伽马测井数据为对象，运用数值模拟技术，有效识别了三叠纪沉积时期的高频沉积旋回，并根据高频沉积旋回的累积厚度偏差变化，反演了古海平面的变化趋势，判断广安地区嘉陵江组5段至雷口坡组1段第1亚段沉积期，相对海平面长期处于较低水位，是最有利的成盐聚钾期，这与基于钻井岩芯划分的富钾层段极为吻合，表明这种方法能够有效识别碳酸盐岩台地含钾层段。
식별해상탄산염암태지심부적성염취갑층단，주요의고측정해역화찬정취심험증。련속침적적탄산염암태지구유선회성，기록착해상탄산염암수고해평면선회변화적신식。인차，이용측정수거모의태지고빈침적선회첩가양식，반연고해평면선회，심조해퇴지층서렬적저수위침적체계，진이쾌속쇄정성염취갑층단적방법치득탐색。문중이사천분지천중엄안지구삼첩계위례，이등간거련속측량적자연가마측정수거위대상，운용수치모의기술，유효식별료삼첩기침적시기적고빈침적선회，병근거고빈침적선회적루적후도편차변화，반연료고해평면적변화추세，판단엄안지구가릉강조5단지뢰구파조1단제1아단침적기，상대해평면장기처우교저수위，시최유리적성염취갑기，저여기우찬정암심화분적부갑층단겁위문합，표명저충방법능구유효식별탄산염암태지함갑층단。
To identify favorable salt-and potash-forming layer, we mainly rely on logging interpretation and coring verification. The continuously carbonate platform shows cyclical growing and recorded valuable information about the facies transition of carbonate rocks, which was synchronized with the relative sea-level cycles. This paper presents a method to preliminarily judge favorable potassium-rich intervals. By using natural gamma ray logging data and numerical simulation, high-frequency sedimentary cycles could be identified effectively from the sedimentary record. Then, we can inverse the distribution model and stacking patterns of these cycles, restore the ancient relative sea-level trends, and finally deduce the favorable salt-and potash-forming phases from the low-stand depositional system. On the basis of these principles, a case study has been taken in the Triassic strata of the Guang’an area, in the central Sichuan Basin. Our result show that the interval between the Fifth Member of the Jialingjiang Formation to the First Member of the Leikoupo Formation is the most potential salt-and potash-forming layer, which is consistent with the potassium-rich layer recognized in the drill cores. It shows that this method could effectively identify potassium rich layer from the marine carbonate platform.