海相油气地质
海相油氣地質
해상유기지질
MARINE ORIGIN PETROLEUM GEOLOGY
2015年
3期
1-9
,共9页
孙春燕%胡明毅%胡忠贵%薛丹%王振鸿
孫春燕%鬍明毅%鬍忠貴%薛丹%王振鴻
손춘연%호명의%호충귀%설단%왕진홍
四川盆地%下三叠统%飞仙关组%层序地层%岩相古地理%碳酸盐岩
四川盆地%下三疊統%飛仙關組%層序地層%巖相古地理%碳痠鹽巖
사천분지%하삼첩통%비선관조%층서지층%암상고지리%탄산염암
Early Triassic%Sequence stratigraphy%Lithofacies paleogeography%Carbonate rock%Sichuan Basin
四川盆地下三叠统飞仙关组发育碳酸盐台地相沉积体系,可划分为开阔台地、局限台地、蒸发台地、台地边缘、台地前缘斜坡和海槽盆地等六种相类型。以单井、野外剖面层序划分和连井层序地层对比为基础,将四川盆地下三叠统飞仙关组划分为两个三级层序(SQ1、SQ2)以及四个高位和海侵体系域,编制了全盆地下三叠统飞仙关组各体系域的层序—岩相古地理平面展布图。研究表明,四川盆地下三叠统飞仙关组自西南向东北的相带分异明显。在SQ1层序时期,四川盆地以开阔台地相和局限台地相沉积为主,在中部和东北部一带发育鲕滩和浅滩微相沉积;在SQ2层序时期,四川盆地的中部和东北部广泛发育局限台地潮坪亚相沉积。指出SQ1层序的高位体系域和SQ2层序的海侵体系域为飞仙关组中的鲕滩最为发育的层位,具有较好的油气勘探潜力。
四川盆地下三疊統飛仙關組髮育碳痠鹽檯地相沉積體繫,可劃分為開闊檯地、跼限檯地、蒸髮檯地、檯地邊緣、檯地前緣斜坡和海槽盆地等六種相類型。以單井、野外剖麵層序劃分和連井層序地層對比為基礎,將四川盆地下三疊統飛仙關組劃分為兩箇三級層序(SQ1、SQ2)以及四箇高位和海侵體繫域,編製瞭全盆地下三疊統飛仙關組各體繫域的層序—巖相古地理平麵展佈圖。研究錶明,四川盆地下三疊統飛仙關組自西南嚮東北的相帶分異明顯。在SQ1層序時期,四川盆地以開闊檯地相和跼限檯地相沉積為主,在中部和東北部一帶髮育鮞灘和淺灘微相沉積;在SQ2層序時期,四川盆地的中部和東北部廣汎髮育跼限檯地潮坪亞相沉積。指齣SQ1層序的高位體繫域和SQ2層序的海侵體繫域為飛仙關組中的鮞灘最為髮育的層位,具有較好的油氣勘探潛力。
사천분지하삼첩통비선관조발육탄산염태지상침적체계,가화분위개활태지、국한태지、증발태지、태지변연、태지전연사파화해조분지등륙충상류형。이단정、야외부면층서화분화련정층서지층대비위기출,장사천분지하삼첩통비선관조화분위량개삼급층서(SQ1、SQ2)이급사개고위화해침체계역,편제료전분지하삼첩통비선관조각체계역적층서—암상고지리평면전포도。연구표명,사천분지하삼첩통비선관조자서남향동북적상대분이명현。재SQ1층서시기,사천분지이개활태지상화국한태지상침적위주,재중부화동북부일대발육이탄화천탄미상침적;재SQ2층서시기,사천분지적중부화동북부엄범발육국한태지조평아상침적。지출SQ1층서적고위체계역화SQ2층서적해침체계역위비선관조중적이탄최위발육적층위,구유교호적유기감탐잠력。
The Lower Triassic Feixianguan sedimentary system of carbonate platform that develops in Sichuan basin consists of six sedimentary facies, including restricted platform facies, open platform facies, evaporite platform facies, platform margin facies, platform foreslope facies and trough basin facies.According to the single-well and outcrop se-quence division and the well-to-well sequence correlation, the Lower Triassic Feixianguan Formation can be divided into a SQ1 and a SQ2 third-order sequences and corresponding HST and TST system tracts. Feixianguan sequence-based lithofacies and paleogeographic maps at each system tract in the whole basin are compiled. It is shown that Feixianguan sedimentary facies presents obvious differentiation from the southwest to the northeast of the basin. During the SQ1 peri-od, the open platform facies and the restricted platform facies commonly developed in the basin but the intraplatform oolitic beach microfacies and the platform-margin shoal microfacies developed in the central and the east of the basin, and during the SQ2 period, the restricted platform tidal flat subfacies widely developed in the central and northeast of the basin. It is concluded that the oolitic beach microfacies deposited in the HST (SQ1) and the TST (SQ2) may be the good reservoirs for exploration potential.