松辽盆地东南缘营城组地层序列的划分与区域对比

Stratigraphical Sequence and Regional Correlation of Yingcheng Formation in the Southeast of Songliao Basin

从营城组沿革分析入手,立足于九台市城子街镇斜尾巴沟—官马山—团结村营城组地表标准剖面的研究,综合运用岩性地层对比、生物地层对比、同位素年代对比和气候事件对比的综合性地层对比方法,对比了松辽盆地东南缘与盆地北部徐家围子断陷20个营城组典型剖面。营城组可划分为5个岩性段,结合地层序列特征和应用习惯,自下而上划分为下段（K1y^下）,一段（K1y^1）,二段（K1y^2）,三段（K1y^3）和四段（K1y^4）。下段以中基性火山岩夹碎屑岩和薄煤层为主,厚度60-478 m,以营城煤矿343孔为标准剖面;一段以厚层流纹岩夹珍珠岩、流纹质火山碎屑岩为主,偶夹复成分砾岩,厚度20-630 m;二段以碎屑岩为主,夹凝灰岩、偶夹流纹岩,含煤层,厚度92-640 m;三段以中基性火山岩、火山碎屑岩为主,顶部为中性、酸性火山岩互层,厚度85-346.5 m;斜尾巴沟-官马山-团结村剖面可作为一段至三段的标准剖面;四段以凝灰质砾岩为主,夹泥岩,仅发育在徐家围子断陷,厚度10-400 m,徐深1井可作为标准剖面。

Stratigraphical correlation is performed on 20 cross and drilling sections at the southeastern margin of the Songliao Basin and in the Xujiaweizi faulted depression. The Yingeheng Formation could be divided into five lithologic members and considering that member 1- member 4 have been in usage in the Xujiaweizi faulted depression, the author have termed the five lithologie members as： lower member （K1y^fow）, member 1 （K1y^1）, member 2 （K1y^2）, member 3 （K1y^3） and member 4 （K1y^4）, in order not to cause more confusion. The lower member consists mostly of andesite basalt, andesite, andesite tuffaceous with conglomerate, sandstone, siltstone and mudstone as interlayers, with Yingcheng 343 drilling hole profile as its standard section. Rhyolite, perlite and rhyolite voleanielastie rocks dominate in member 1. Member 2 is mostly of clastic rocks, including conglomerate, sandstone, siltstone, mudstone with tuff as interlayers in the lower part and rhyolitic volcaniclastic rocks at the top of the member. Member 3 is composed of basalt, basaltic tuffaceous rocks at the lower and middle parts while at the top of the member of intebedding of the intermediate with acidic volcanic rocks. Xieweibagou- Guanmashan-Tuanjie cross-section can be selected as the standard section of member 1, member 2 and member 3. Member 4 consists mostly of conglomerate, samdwiched in sandstone and mudstone, with the Xushen 1 drilling hole profile as its standard section. Member 4 only exists in the Xujiaweizi faulted depression.