兰州大学学报(自然科学版)
蘭州大學學報(自然科學版)
란주대학학보(자연과학판)
JOURNAL OF LANZHOU UNIVERSITY(NATURAL SCIENCES)
2013年
3期
320-326,331
,共8页
唐俊%王琪%廖朋%郝乐伟%田兵%庞国印
唐俊%王琪%廖朋%郝樂偉%田兵%龐國印
당준%왕기%료붕%학악위%전병%방국인
埋藏史%成岩作用%孔隙度演化%定量模拟%环县地区
埋藏史%成巖作用%孔隙度縯化%定量模擬%環縣地區
매장사%성암작용%공극도연화%정량모의%배현지구
burial history%diagenesis%porosity evolution%quantitative simulation%Huanxian aera
在充分分析研究区长8段砂岩储层特征、主控因素及地层埋藏史和成岩史的基础上,应用数理统计方法,以现今孔隙度为约束条件,将孔隙度演化分为减小和增大两个过程,分别建立了鄂尔多斯盆地环县地区长8段砂岩储层从埋藏初始至现今的孔隙度随埋藏深度和地史时间变化的演化模型。结果表明孔隙度定量演化模型为一个4段式分段函数。机械压实和胶结阶段为孔隙度减小模型,是对埋深和埋藏时间的指数函数。次生增孔是由于地层酸性流体的溶蚀作用而产生的,主要发生在80~100?C的温度窗口内。因此,溶蚀阶段为孔隙度增大模型,是对埋深、埋藏时间及增孔过程的复合函数。溶蚀阶段结束后地层孔隙度为压实和保持阶段。最后进行实例验证,验证结果表明该方法建立的砂岩孔隙度定量演化模型符合地质实际,具有较好的应用效果。
在充分分析研究區長8段砂巖儲層特徵、主控因素及地層埋藏史和成巖史的基礎上,應用數理統計方法,以現今孔隙度為約束條件,將孔隙度縯化分為減小和增大兩箇過程,分彆建立瞭鄂爾多斯盆地環縣地區長8段砂巖儲層從埋藏初始至現今的孔隙度隨埋藏深度和地史時間變化的縯化模型。結果錶明孔隙度定量縯化模型為一箇4段式分段函數。機械壓實和膠結階段為孔隙度減小模型,是對埋深和埋藏時間的指數函數。次生增孔是由于地層痠性流體的溶蝕作用而產生的,主要髮生在80~100?C的溫度窗口內。因此,溶蝕階段為孔隙度增大模型,是對埋深、埋藏時間及增孔過程的複閤函數。溶蝕階段結束後地層孔隙度為壓實和保持階段。最後進行實例驗證,驗證結果錶明該方法建立的砂巖孔隙度定量縯化模型符閤地質實際,具有較好的應用效果。
재충분분석연구구장8단사암저층특정、주공인소급지층매장사화성암사적기출상,응용수리통계방법,이현금공극도위약속조건,장공극도연화분위감소화증대량개과정,분별건립료악이다사분지배현지구장8단사암저층종매장초시지현금적공극도수매장심도화지사시간변화적연화모형。결과표명공극도정량연화모형위일개4단식분단함수。궤계압실화효결계단위공극도감소모형,시대매심화매장시간적지수함수。차생증공시유우지층산성류체적용식작용이산생적,주요발생재80~100?C적온도창구내。인차,용식계단위공극도증대모형,시대매심、매장시간급증공과정적복합함수。용식계단결속후지층공극도위압실화보지계단。최후진행실례험증,험증결과표명해방법건립적사암공극도정량연화모형부합지질실제,구유교호적응용효과。
Thin section analysis indicated that the diagenesis of the sandstone reservoir in the research area had mainly undergone the processes of compaction, cementation and dissolution. Combined with the mathe-matical statistics method, the methodology was based on an analysis of tight sandstone reservoir characteristics, controlling factors and a study of the burial history and diagenetic history of the study area. With current porosity as boundary constraint conditions, the geological time and burial depth as variables, the whole porosity evolution from initial burial until the present was divided into two independent processes: porosity decrease and porosity increase, for which two mathematical models were established respectively. The quantitative simulation result indicates that the whole porosity-evolution quantitative simulation was a piecewise function with four sections. That is, the porosity decrease model for the mechanical compaction and cementation stages served a continuous exponential function with the geological time and burial depth as the variables, and the secondary porosity increase was caused by organic acid dissolution within a temperature window of 80~100?C. Therefore, the dissolution phase was of a porosity increase model, which was a composite function of the depth, burial time and porosity decrease amount. After the dissolution phase, the porosity was in the phase of compaction and maintenance. Finally, through the exemplification, it was verified that the porosity-evolution quantitative simulation established by the present researcher is consistent with actual geological conditions and can be applied to porosity calculation of any stratum in the study area.