發(fā)布時(shí)間：2019-06-07 18:48

【摘要】：四川盆地東北部廣泛發(fā)育有上二疊統(tǒng)長興組的生物礁灘組合相,而生物礁-灘組合相為重要的油氣儲集巖發(fā)育地區(qū),故對該生物礁灘組合相帶的分布及其發(fā)育特征的研究具有重要意義。眾所周知,沉積相帶的分布又受控于構(gòu)造運(yùn)動,因而通過對生物礁灘的發(fā)育分布與峨眉地裂運(yùn)動的關(guān)系研究能更好的指導(dǎo)油氣勘探。 通江鐵廠河上二疊統(tǒng)長興組生物礁是川東北地區(qū)地表發(fā)現(xiàn)的生物礁的又一代表,通過野外4條剖面的測制及詳細(xì)的室內(nèi)研究,認(rèn)為該區(qū)長興組發(fā)育有生物礁及生物碎屑淺灘組合相,圓丘狀點(diǎn)礁與淺灘疊置構(gòu)成縱向上三個旋回的礁、灘復(fù)合體。生物礁的造礁生物主要為海綿,含量20%～50%,附礁生物主要有藻類、有孔蟲、蜓類等,主要造礁方式為障積作用。單個礁體的發(fā)育規(guī)模雖然較小,但其組合相帶特征明顯,下部礁基為灰色中-厚層生物屑泥粒巖,含生物碎屑較多;礁核部發(fā)育有形態(tài)完整的串管海綿,長5～8cm,寬約3～6cm,海綿直立生長,也有橫臥生長;礁蓋及礁頂發(fā)育薄-中層生物屑泥粒巖及細(xì)晶白云巖;礁翼見有燧石結(jié)核;礁間為厚度較大的生物碎屑淺灘沉積。 儲層巖性主要以礁灰?guī)r及生物屑亮晶灰?guī)r為主,巖石白云化程度較低�？锥摧^豐富,但多被方解石晶體充填。儲層經(jīng)過多種成巖作用的改造,主要包括壓實(shí)壓溶作用、泥晶化、膠結(jié)、重結(jié)晶、白云石化、溶蝕和破裂作用。對儲集巖起建設(shè)作用的主要是溶蝕、白云石化和破裂作用。 通過與同位于開江-梁平坳拉槽東段臺地邊緣淺灘相帶上的普光、黃龍及盤龍洞地區(qū)的生物礁灘發(fā)育特征的對比,認(rèn)識到峨眉地裂運(yùn)動對于川東北地區(qū)生物礁灘組合相帶的分布確實(shí)有控制作用,并具體分析了各地區(qū)生物礁、灘發(fā)育的特征,指出開江-梁平坳拉槽東段碳酸鹽臺地總體向北西傾斜,北部、西部地勢低,南部、東部地勢高。
[Abstract]:The reef beach assemblage of Changxing formation of Upper Permian is widely developed in the northeast of Sichuan Basin, and the reef beach assemblage is an important area of oil and gas reservoir rock development. Therefore, it is of great significance to study the distribution and development characteristics of the reef beach assemblage zone. As we all know, the distribution of sedimentary facies belt is controlled by tectonic movement, so the study of the relationship between the development and distribution of reef beach and Emei ground fissures movement can better guide oil and gas exploration. The reef of Changxing formation of Upper Permian in Tiechang River, Tongjiang River, is another representative of the reef found on the surface of Northeast Sichuan. Through the survey and detailed laboratory study of four profiles in the field, It is considered that there are reef and bioclastic shoal assemblage in Changxing formation in this area, and the round dune reef and shoal overlap to form the reef and beach complex with three cycles longitudinally. The reef-building organisms are mainly sponges, the content of which is 20% 鈮，

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