PALEOMAGNETIC ESTIMATE OF THE MESOZOIC—CENOZOIC LATITUDINAL DISPLACEMENT OF TERRENES IN THE QINGHAI—TIBET PLATEAU AND ITS SIGNIFICANCE

PALEOMAGNETIC ESTIMATE OF THE MESOZOIC—CENOZOIC LATITUDINAL DISPLACEMENT OF TERRENES IN THE QINGHAI—TIBET PLATEAU AND ITS SIGNIFICANCE1　QianFang ,PreliminarystudyonthehorizontalmovementofNgariarea ,Tibet,sincePliocene[A].AbstractfromInterna tionalSymposiumonHimalayaGeologySciences[C].1984,2 49～ 2 5 0 . 2　JiangChunfa .OpeningandclosingstructuresofKunlun[M ].Beijing :GeologicalPublishingHouse ,1992 ,15 4～ 2 17. 3　XuZhiqin ,…     

FINITE STAIN MEASUREMENT AND SHORTENING ANALYSIS IN THE NORTHERN MARGIN OF QINGHAI—TIBET PLATEAU

FINITE STAIN MEASUREMENT AND SHORTENING ANALYSIS IN THE NORTHERN MARGIN OF QINGHAI—TIBET PLATEAU     

TWO TYPES OF XENOLITH—MANTLE XENOLITH AND CRUSTAL XENOLITH FOUND IN THE CENOZOIC VOLCANIC ROCKS FROM HOH XIL, NORTHERN TIBET PLATEAU

TWO TYPES OF XENOLITH—MANTLE XENOLITH AND CRUSTAL XENOLITH FOUND IN THE CENOZOIC VOLCANIC ROCKS FROM HOH XIL, NORTHERN TIBET PLATEAU1　YangJingsui,XuZhiqin ,BaiWenji,etal.CenozoicvolcanismontheQinghai Tibetplateauanditsgenesis[J].ContinentalGeodynamics ,1997(2 ) :1～ 11. 2　XuZhiqin ,JiangMei,etal.Mantlediapirandinwardintracontinentalsubduction :AdiscussiononthemechanismofupliftoftheQinghai TibetPlateau[A].MacfarlaneA ,Sorkabi,RB ,…     

GEOMORPHIC EVIDENCES FOR CENOZOIC UPLIFT IN THE EASTERN MARGIN OF QINGHAI—TIBET PLATEAU

GEOMORPHIC EVIDENCES FOR CENOZOIC UPLIFT IN THE EASTERN MARGIN OF QINGHAI—TIBET PLATEAU     

MARINE SOURCE ROCKS AND THEIR DEPOSITIONAL CONDITIONS OF MESOZOIC—CENOZOIC IN THE GAMBA—TINGRE BASIN,SOUTH TIBET:ORGANIC GEOCHEMICAL STUDY

MARINE SOURCE ROCKS AND THEIR DEPOSITIONAL CONDITIONS OF MESOZOIC—CENOZOIC IN THE GAMBA—TINGRE BASIN,SOUTH TIBET:ORGANIC GEOCHEMICAL STUDY1　FuJiamo ,ShengGuoying ,XuJiayou,et.al.ApplicationofbiologicalmarkersintheassessmentofpaleoenvironmentsofChinesenon marinesediments[J] .OrganicGeochemistry ,1990 ,16 :76 9～ 779. 2　JenkynsHC .Cretaceousanoxicevents:fromcontinentstooceans[J] .JournaloftheGeologicalSociety ,1980 ,137:171～188. …     

THE CENOZOIC GEORECORDS IN THE NORTHWEST OF YUNNAN AND THE EVOLUTION OF QING—ZANG PLATEAU

THE CENOZOIC GEORECORDS IN THE NORTHWEST OF YUNNAN AND THE EVOLUTION OF QING—ZANG PLATEAU     

CENOZOIC TECTONIC EVOLUTION AND GEODYNAMICS OF KEKEXILI BASIN IN NORTHERN QINGHAI—XIZANG PLATEAU

CENOZOIC TECTONIC EVOLUTION AND GEODYNAMICS OF KEKEXILI BASIN IN NORTHERN QINGHAI—XIZANG PLATEAU     

THE TERTIARY STRATIGRAPHIC SEQUENCE OF YANYUAN BASIN IN THE SOUTHEASTERN MARGIN OF THE QINGHAI—TIBET PLATEAU

THE TERTIARY STRATIGRAPHIC SEQUENCE OF YANYUAN BASIN IN THE SOUTHEASTERN MARGIN OF THE QINGHAI—TIBET PLATEAUYoungGeologistofGMR(Qn979816 )andNSFCGeneralProjects(4980 2 0 13)     

GEOLOGICAL EVOLUTION AND OROGENY OF EAST KUNLUN TERRAIN ON THE NORTHERN QINGHAI—TIBET PLATEAU

GEOLOGICAL EVOLUTION AND OROGENY OF EAST KUNLUN TERRAIN ON THE NORTHERN QINGHAI—TIBET PLATEAU1　XuZQ ,YangJS ,ZhangJX ,etal.AcomparisonbetweenthetectonicunitsonthesidesoftheAltunsinistralstrike slipfaultandthemechanismoflithosphericshearing[J] :ActaGeologicaSinica,1999,73:193～ 2 0 5(inChinesewithEnglishabstract) . 2　YangJS ,XuZQ ,LiHB ,Wu ,etal.DiscoveryofeclogiteatthenorthernmarginofQaidambasin,NWChina[J] .Chi neseScienceBulletin,1998,4 3…     

THE NUMERICAL SIMULATE OF THE UPLIFT PROCESS OF THE QINGHAI—TIBET PLATEAU

THE NUMERICAL SIMULATE OF THE UPLIFT PROCESS OF THE QINGHAI—TIBET PLATEAU     

西藏奥陶纪和志留纪海相红层的分布与时代

本文对曾经考察过的西藏自治区主要研究剖面(即:聂拉木、定日、定结和申扎剖面)重新研究,参照国内已知的西藏奥陶纪和志留纪地层资料,对西藏地区奥陶系和志留系的海相红层进行系统研究。在西藏奥陶—志留系中,识别出11层海相红层。其中,在奥陶纪地层中识别出6层海相红层,在志留纪地层中识别出5层海相红层。已识别出的11层海相红层中,除奥陶纪青泥洞组海相红层(XORB1)属于深水大洋红层外,其它10层海相红层均属于浅水-半深水的陆棚红层。依据海相红层及其上下层位所含化石,本文初步讨论了各海相红层的大致时代,并与我国主要地区的同期海相红层进行了对比。     

Burial Records of Reactive Iron in Cretaceous Black Shales and Oceanic Red Beds from Southern Tibet

One of the new directions in the field of Cretaceous research is to elucidate the mechanism of the sedimentary transition from the Cretaceous black shales to oceanic red beds. A chemical sequential extraction method was applied to these two types of rocks from southern Tibet to investigate the burial records of reactive iron. Results indicate that carbonate-associated iron and pyrite are relatively enriched in the black shales, but depleted or absent in red beds. The main feature of the reactive iron in the red beds is relative enrichment of iron oxides （largely hematite）, which occurred during syn-depostion or early diagenesis. The ratio between iron oxides and the total iron indicates an oxygen-enriched environment for red bed deposition. A comparison between the reactive iron burial records and proxies of paleo-productivity suggests that paleo-productivity decreases when the ratio between iron oxides and the total iron increases in the red beds. This phenomenon could imply that the relationship between marine redox and productivity might be one of the reasons for the sedimentary transition from Cretaceous black shale to oceanic red bed deposition.     

Response of Reactive Phosphorus Burial to the Sedimentary Transition from Cretaceous Black Shales to Oceanic Red Beds in Southern Tibet

The mechanism of sedimentary transition from the Cretaceous black shales to the oceanic red beds is a new and important direction of Cretaceous research. Chemical sequential extraction is applied to study the burial records of reactive phosphorus in the black shale of the Gyabula Formation and oceanic red beds of the Chuangde Formation, Southern Tibet. Results indicate that the principal reactive phosphorus species is the authigenic and carbonate-associated phosphorus (CaP) in the Gyabula Formation and iron oxides-associated phosphorus (FeP) in the Chuangde Formation which accounts for more than half of their own total phosphorus content. While the authigenic and carbonate-associated phosphorus (CaP) is almost equal in the two Formations; the iron oxides-associated phosphorus is about 1.6 times higher in the Chuangde Formation than that in the Gyabula Formation resulting in a higher content of the total phosphorus in the Chuangde Formation. According to the observations on the marine phosphorus cycle in Modern Ocean, it is found that preferential burial and regeneration of reactive phosphorus corresponds to highly oxic and reducing conditions, respectively, leading to the different distribution of phosphorus in these two distinct type of marine sediments. It is the redox-sensitive behavior of phosphorus cycle to the different redox conditions in the ocean and the controlling effects of phosphorus to the marine production that stimulate the local sedimentary transition from the Cretaceous black shale to the oceanic red beds.     

冀西北张北康保一带新生代红层的地质特征

冀西北坝上高原的张北、康保等地发育着两套新生代红层,分别为上新世石匣组和中更新世赤城组.石匣组为一套深红、绛红色的粘土、砂砾层,岩性、岩相变化大,其中含有丰富的具铁锰质薄膜的钙质结核和黑色锰质斑点,并有丰富的三趾马动物群化石和孢粉.孢粉中喜暖喜湿分子约占19 %,形成于炎热湿润气候条件下,与现代北亚热带气候条件相似.赤城组为一套冲洪积红黄色亚粘土夹棕红色粘土、砂组成,分布较为局限,含个体小、形状不规则的钙质结核,并有周口店动物群的化石分子和孢粉.孢粉中以中性喜温的松属占绝对优势,喜暖喜湿的分子约占7.6 %,形成于温和较湿润气候条件下.     

华南志留系红层的时代

华南志留系红层有三个形成期,“下红层”形成于晚Ａｅｒｏｎｉａｎ至早Ｔｅｌｙｃｈｉａｎ期;“上红层”主要形成于晚Ｔｅｌｙｃｈｉａｎ期;第三套红层形成于Ｌｕｄｌｏｗ期,但在Ｏ．ｃｒｉｓｐａ牙形刺带之前。每套红层的时代各地不同,有穿时现象。     

Magnetostratigraphy of the Red Beds in the Hengyang Basin

Abstract This paper discusses the Cretaceous-Tertiary magnetic polarity sequence of the the Hengyang Basin on the basis of magnetostratigraphic study. The age of each stratigraphic unit has been determined with the magnetic polarity time scale combined with ³⁹Ar/⁴⁰Ar dating, thus providing evidence for determining the geological ages of different formations. The authors assign the age of the Dongjing Formation of the Hengyang Basin to Early Cretaceous, the Shenhuangshan Formation to Early-Late Cretaceous, the Daijiaping Formation to Late Cretaceous, and the Dongtang and Xialiushi formations to Palaeocene.     

Magnetostratieraphy of the Red Beds in the Hengyang Basin

This paper discusses the Cretaceous-Tertiary magnetic polarity sequence of the the Hengyang Basin on the basis of magnetostratigraphic study. The age of each stratigraphic unit has been determined with the magnetic polarity time scale combined with 39Ar/40Ar dating, thus providing evidence for determining the geological ages of different formations. The authors assign the age of the Dongjing Formation of the Hengyang Basin to Early Cretaceous, the Shenhuangshan Formation to Early-Late Cretaceous, the Daijiaping Formation to Late Cretaceous, and the Dongtang and Xialiushi formations to Palaeocene.     

西秦岭北缘漳县中-新生代红层地层格架厘定及其地质意义

西秦岭北缘漳县地区分布的中-新生代红层地层格架和时代一直存在争议.该地区红层地层格架的正确厘定对于重建西秦岭北缘中-新生代构造地貌演化过程和认识印度-欧亚板块汇聚碰撞过程在青藏高原东北缘的远程地质响应具有重要的科学意义.通过对红层地层与下伏老地层以及不同红层地层之间的角度不整合、红层沉积序列及岩石学特征和红层地层与西秦岭北缘断层之间关系的研究,结合孢粉分析资料,重新厘定了西秦岭北缘漳县地区的红层沉积地层地质格架.研究表明,西秦岭漳县地区分布的中-新生代红层地层自下而上可分为三套地层系统,即①下白垩统紫红色砂岩、砾岩.②中新统红色砾岩、砂岩、黏土岩和深紫色-灰色泥岩、灰色泥灰岩、蒸发岩系.③上新统河流相砾岩层(韩家沟砾岩)和F1断层以北的红色洪积砾岩层.三套红层地层之间都为角度不整合面分割,相对地质关系清晰,沉积岩石特征差异明显,尽管由于断层的破坏,但没有影响到整体地层格架.三套红层地层系统反映了西秦岭北缘中-新生代不同阶段的沉积构造环境和古地貌演化过程,为研究西秦岭中-新生代陆内构造过程和青藏高原隆升、构造变形向东北缘的扩展远程效应等科学问题提供了基本的地质约束.     

综合电法在红层地区地下水勘探中的应用

在胶莱盆地,其红层所属地层岩性为粉砂岩、泥岩,含、透水性较差,查找低阻断裂构造是其地下水勘探的唯一途径。而红层地区的压扭性断层,会因挤压密实的断层泥存在,导致单纯利用低电阻率参数判定地下水的赋存位置出现差错。根据该区地下水的自然电位异常值约为-100mV、含水破碎砂岩极化率大于2％、衰减度D大于50％的特点,提出了自然电位观测法与激发极化电测深法相结合的组合方法。即利用自然电场法进行剖面测量,判定含水异常位置,然后利用激发极化电测深法准确判定地下水所在层位及埋深。在胶州市某镇政府水源勘探中,利用该组合方法,成功的圈定了3个井位,并在预定的深度内打出了单井出水量为1000t／d的优质井。     

A Preliminary Study on the Red Beds in the Northern Heyuan Basin, Guangdong Province, China

The red beds of the northern Heyuan Basin （Guangdong Province, China） are more than 4,000 m thick. Based on the lithological characters, in ascending order these beds are divided into the Dafeng Formation, Zhutian Formation, and Zhenshui Formation of the Nanxiong Group, Shanghu Formation and Danxia Formation. The Nanxiong Group with relatively mature coarse clastic rocks attains about 2940 m in thickness. The Dafeng Formation is 837 m thick, consisting of conglomerates and sandy conglomerates; the Zhutian Formation, which is 1.200 m thick, consists of purplish red sandstone with gravels, poorly sorted sandstone, feldspathic quartzose sandstone banded granular conglomerate, siltstone, and sandy mudstone. The Zhutian Formation is rich in calcareous concretions. Heyuannia （Oviraptoridae） and turtle fossils were found in this formation. The Zhenshui Formation deposited to a thickness of 900 m consists of coarse sediments, including granular conglomerate, and gravelly sandstone with well developed cross-beddings; the Shanghu Formation, which is 820 m thick, consists of purplish red granular conglomerate coarse sandstone intercalated with fine si~tstone; the Danxia Formation characterized by the Danxia ~andform is composed of coarse c~astic gravels and sandy gravels. The lower part of the Nanxiong Group whence dinosaur eggs and derived oviraptorosaurs come, belongs to the Late Cretaceous. No fossils are found in the Shanghu Formation or the Danxia Formation, but their stratigraphic order of superposition on the Nanxiong Group clearly shows their younger age.