西准噶尔洪古勒楞组及泥盆-石炭系界线

<正> 新疆西准噶尔和布克赛尔蒙古自治县的沙尔布尔提山一带,上泥盆统发育,其下部称朱鲁木特组,为陆相地层,上部为洪古勒楞组,下石炭统称为黑山头组。洪古勒楞组建于1979年(曾亚参、肖世禄1979,侯鸿飞等1979)。1985年笔者重测洪古勒楞组的命名剖面,发现它可能位于向斜构造上,地层有重复,缺失与石炭系接触的上部地层;此外发现三个泥盆—石炭系的连续剖面。

Hongguleleng Formation in Western Junggar and the boundary between Devonian and Carboniferous

The Hongguleleng Formation (sensus nov.) is widespread in Hoboksar district of western Junggar basin, Xinjiang.It may be.subdivided into three parts.The lower part is about 120m tick and consists of medium-or thin-bedded limestone, argillaceous limestone, marl and calcareous mudstone, containing Sinoprodnciclla sp., Ptychomaloioechia luranica, Cyrtospirifer sulcifcr, Amplexocarinia tenuiseptata, Ammonidittm grosjeani, Cymatiosphaera par vicar ina, Asfertspora cf.acuta, Crassispora rctnota etc.They may be early Famennian in age.The middle part is composed of variegated siliceous shale, calcareous mudstone and silty mudstone and about 160m thick, with Nalivfyinella profunda, Guerichiphyllum sinen-se.Planovatirosirum planoovalis.It is worth to indicate that a few conodonts Polygnathus bomorire^u-laris, P.granlosus, Palmatolepis grabra have also been found in this part.Therefore, the middle part may be roughly correlatetd with the Famennian Ⅱ-Ⅴ of Europe.The upper part is 22m thick arid consists of yellow-green calcareous mudstone intercalated with brown thick-bedded marl, containing Pa.rapugnax sp., Spinulicosta sp., Meiriophyllum omhaense, Cyathocprinia xinjiangensis, Polygnathus com-munis, Protognathus collisoni, P.mcischneri, Vcrrucosisporites nfitidusr, Hytynenazoifetrilctes praetervisus.This part may be corresponded with Famennian Ⅵ of Europe.The Lower Carboniferous Heishantou Formation comformably overlies the Hongguleleng Formation; its basal part is composed of alternating yellow-green calcareous muds tine and brown marl, containing Plicatifera sp., Syringothyris typus, Vallatisporites verrucosus, Reiusotriletcs mcohatus, Siphonodclla coo-peri.It is no doubt that the deposit from Devonian to Lower Carboniferous in this district is continuous.