水城—納雍地區(qū)構(gòu)造控制下的煤層氣成藏特征

水城—納雍地區(qū)構(gòu)造控制下的煤層氣成藏特征

竇新釗，俞顯忠，胡廣青，趙志義，易小會(huì)，朱建剛

(安徽省煤田地質(zhì)局勘查研究院，安徽合肥 230088)

摘要：貴州省煤層氣資源豐富，水城—納雍地區(qū)是研究煤層氣成藏特征的有利區(qū)域。本文在系統(tǒng)分析煤層氣成藏地質(zhì)背景的基礎(chǔ)上，結(jié)合構(gòu)造埋藏史和生烴演化史數(shù)值模擬研究，探討水城—納雍地區(qū)煤層氣成藏特征及構(gòu)造對(duì)成藏的控制作用。結(jié)果表明，在煤田勘探資料約束下，數(shù)值模擬結(jié)果可信，過程合理，較好地反映了水城—納雍地區(qū)上二疊統(tǒng)煤層的構(gòu)造埋藏史和生烴演化史。在構(gòu)造作用控制下，水城—納雍地區(qū)具有如下煤層氣成藏特征：向斜控氣；中新生代構(gòu)造抬升劇烈，氣藏埋深小；多期生烴作用，煤層氣含量高；成藏過程復(fù)雜且分異明顯。

關(guān)鍵詞：水城—納雍地區(qū)；煤層氣；成藏特征；構(gòu)造控制；數(shù)值模擬

中圖分類號(hào)：P618.11

基金項(xiàng)目：國(guó)家自然科學(xué)

作者簡(jiǎn)介：第一竇新釗(1985年生)，男，博士，工程師,2012年畢業(yè)于中國(guó)礦業(yè)大學(xué)，現(xiàn)從事構(gòu)造地質(zhì)及非常規(guī)天然氣地質(zhì)研究工作。郵箱：douxinzhao@163.com。

Characteristics of CBM Reservoir Formation under Tectonic

Control in Shuicheng-Nayong Area

Dou Xinzhao, Yu Xianzhong, Hu Guangqing, Zhao Zhiyi, Yi Xiaohui, Zhu Jiangang

(ExplorationandResearchInstitute,AnhuiBureauofCoalGeologicalExploration,Hefei,Anhui230088,China)

Abstract:There are rich coalbed methane (CBM) resources in Guizhou Province, and Shuicheng-Nayong area is favorable for study on CBM reservoir forming characteristics. So, based on the system analysis of geologic setting of CBM reservoir forming, combined with the modeling study of tectonic burial history and mature evolution history, the reservoir forming characteristics of CBM and its tectonic control of reservoir forming in Shuicheng-Nayong area were discussed. The research showed that the results of numerical simulation were reliable, and process was rational under the constraints of coal, exploration data, tectonic burial history and mature evolution history of upper Permian coal seams in Shuicheng-Nayong area were reflected well. CBM reservoir formation under tectonic control in Shuicheng-Nayong area has the following features: it is characterized by syncline-controlled gas; the scope of tectonic uplift is large in Mesozoic-Cenozoic, and the depth of CBM reservoir is small; CBM content is high for multiple phases of hydrocarbon generation; the process of CBM reservoir formation is complex and fractionation in different zone is clear.

Key words: Shuicheng-Nayong area; CBM; reservoir forming characteristics; tectonic control; numerical simulation

構(gòu)造演化在煤層氣成藏過程中具有根本性的控制作用[1-3]，在構(gòu)造作用下，煤系地層遭受沉降埋藏和抬升剝蝕，從而控制著煤的受熱—成熟—生烴—散失整個(gè)過程[4,5]。貴州省煤層氣資源豐富，主要賦存于上二疊統(tǒng)煤系，但處于特提斯構(gòu)造域和濱太平洋構(gòu)造域的結(jié)合部位，構(gòu)造演化過程極為復(fù)雜[6,7]，嚴(yán)重制約了煤層氣的勘探開發(fā)進(jìn)程。貴州省中西部的水城—納雍地區(qū)構(gòu)造變形強(qiáng)烈，煤層含氣量高，是研究煤層氣成藏過程和差異性的有利區(qū)域。……