新疆农业地貌分类：以编制新疆1：100万农业地貌图为例

针对新疆地域辽阔，地形起伏巨大，山地层状地貌显著，盆地封闭、干旱，风成和流水地貌发育等特点，着眼于地貌与农业的关系，采用形态与成因相结合的分类原则，以地貌与农业关系密切的海拔高程、物质组成、相对高差、坡度等要素为指标，制定新疆农业地貌分类系统，划分农业地貌类型。     

延庆盆地北缘断裂带蚕房营段晚更新世晚期断层作用

通过１个探槽记录、３个地质学剖面、７个晚更新世沉积物表面断层崖形态学剖面和１５个放射性测年数据，论述了延庆盆地北缘断裂带蚕房营段的晚更新世晚期断层作用。这些资料显示出该时期内的两次断层作用事件：最近的一次发生在９８７０±１３０～１１８００±１１００ａＢ．Ｐ．之间，最早不超过１３２００±ｌ１００ａＢ．Ｐ．；较早一次的发生时间为１９８５０±１５５０ａＢ．Ｐ．。一次事件的位移量３．３４～３．６４ｍ，两次事件之间的重复间隔９９８０ａ。大约自２１０５０±１６００ａＢ．Ｐ．以来的垂直位移速度计算为０．３１～０．３４ｍｍ／ａ。蚕房营段的晚更新世晚期的断层作用，以较大的表面位移量和较长的重复间隔为特征。全新世没有类似的断层作用事件     

论五指石旅游区的个性及开发策略

本文运用旅游地理学，旅游市场学基本原理，分析了五指石旅游区的个性特征，结合其区位和经济条件，论述了将来的开发策略，认为应以建议好山寨门为突破口进行旅游区的整体形象建设，注意各景区重点及其与其它设施的配套规划，迅速解决交通与缺水问题，集约开发系列旅游产品以增强旅游总体效益。     

Block gliding and rheological deformation in the Southern Sydney basin

Block gliding caused by low frictional resistance or by the deformation of plastic substrates has been well documented from many parts of the world, but neither of these mechanisms explains the widespread gliding of sandstone blocks away from cliffs in the southern Sydney Basin of south‐eastern Australia. The movement of large blocks over declivities from near zero to a maximum of 5°, high frictional resistance and lack of high porewater pressures rule out a simple sliding mechanism and it is unlikely that slender towers of sandstone could have survived seismic vibration sufficient to overcome frictional resistance to gliding. Highly preferential dip control of the direction of gliding and of the development of benches over which the blocks move, together with mounds, similar to pressure ridges, on the benches, indicate that the block gliding is due to the rheological deformation of the underlying rock, even though it is a sandy siltstone lacking readily deformable beds. Estimated rates of deformation are only 11 m/Ma to 270 m/Ma, but are commensurate with the rates of erosional retreat of clifflines estimated from K‐Ar and ¹⁴C chronologies. This phenomenon may be a significant feature of many slowly eroding landscapes, and prompts revision of models of long‐term geomorphological evolution.     

攀西裂谷及邻区构造应力场演化与叠加断裂作用

攀西裂谷形成和演化包含四个构造期:1)加里东期;2)海西晚期;3)印支早期和4)印支晚期。加里东期和海西晚期,地壳受近东西向张应力。印支早期区域张应力方向为北西西—南东东,裂谷断陷。印支晚期构造运动应力特征是北西西—南东东方向压缩,裂谷闭合、消亡。燕山期区域最大主应力方向仍是北西西—南东东。喜山期以块断作用为主。喜山期、燕山期和印支期的构造应力使它们古老的断裂产生叠加断裂作用。     

Three-dimensional SeaMARC II,gravity, and magnetics study of large-offset rift propagation at the Pito Rift,Easter microplate

We present results from a SeaMARC II bathymetry, gravity, and magnetics survey of the northern end of the large-offset propagating East Rift of the Easter microplate. The East Rift is offset by more than 300 km from the East Pacific Rise and its northern end has rifted into approximately 3 Ma lithosphere of the Nazca Plate forming a broad (70–100 km) zone of high (up to 4 km) relief referred to as the Pito Rift. This region appears to have undergone distributed and asymmetric extension that has been primarily accommodated tectonically, by block faulting and tilting, and to a lesser degree by seafloor spreading on a more recently developed magmatic accretionary axis. The larger fault blocks have dimensions of 10–15 km and have up to several km of throw between adjacent blocks suggesting that isostatic adjustments occur on the scale of the individual blocks. Three-dimensional terrain corrected Bouguer anomalies, a three-dimensional magnetic inversion, and SeaMARC II backscatter data locate the recently developed magmatic axis in an asymmetric position in the western part of the rift. The zone of magmatic accretion is characterized by an axis of negative Bouguer gravity anomalies, a band of positive magnetizations, and a high amplitude magnetization zone locating its tip approximately 10 km south of the Pito Deep, the deepest point in the rift area. Positive Bouguer gravity anomalies and negative magnetizations characterize the faulted area to the east of the spreading axis supporting the interpretation that this area consists primarily of pre-existing Nazca plate that has been block faulted and stretched, and that no substantial new accretion has occurred there. The wide zone of deformation in the Pito Rift area and the changing trend of the fault blocks from nearly N-S in the east to NW-SE in the west may be a result of the rapidly changing kinematics of the Easter microplate and/or may result from ridge-transform like shear stresses developed at the termination of the East Rift against the Nazca plate. The broad zone of deformation developed at the Pito Rift and its apparent continuation some distance south along the East Rift has important implications for microplate mechanics and kinematic reconstructions since it suggests that initial microplate boundaries may consist in part of broad zones of deformation characterized by the formation of lithospheric scale fault blocks, and that what appear to be pseudofaults may actually be the outer boundaries of tectonized zones enclosing significant amounts of stretched pre-existing lithosphere.     

Geomorphologic Study of Anhui Section of Changjiang River Using Landsat TM Image

Fluvial landforms in the Anhui section of the Changjiang(Yangtze)River are often considered as the main factors for frequent floods.It is these special landforms that influence the channel changes of the Changjiang River.Using Landsat TM image of 2000,this paper conducted a series of image processing,including principal component analysis,multi-spectral composition,gray value statistics,and spectral analysis of ground objects.Then it got a new interpretation map of different kinds of fluvial landforms of the Changjiang River in the Anhui section.Based on the interpretation mentioned above,the paper analyzes the distribution and characteristics of such typical landforms as terraces,floodplains and battures,and their functions on the changes of river channel.The results show a consistence with the earlier conclusion that the Anhui section of the Changjiang River tends to deflect gradually toward south,which provides more implications for further study on the geomorphologic evolution of the river channel.     

The genesis, mineralization, and stratigraphic significance of phosphatic/glauconitic condensed limestone unit in the Manavgat Basin, SW Turkey

A condensed hemipelagic limestone unit with glauconite and phosphate separates a drowned Late Burdigalian carbonate platform from overlying Langhian pelagic mudstones, marls, and calcarenitic tempestites within the Neogene Manavgat Basin of southwestern Anatolia, Turkey. The unit consists of coeval lenticular limestone bodies, between 1 cm and 15 m in thickness, ranging from 10 m to 3 km in lateral extent. The P2O5 content of this limestone ranges from 0.2 to 10% by weight and the iron-oxide, clay, and other metal-oxide contents of this unit substantially exceed those of the underlying and overlying rocks.This condensed stratigraphic unit was deposited on the southwesterly outer shelf portions of drowned horsts that directly faced upwelling currents. The unit displays three main facies: 1) glauconitic phosphate crusts associated with hardgrounds; 2) bedded glauconitic-phosphatic limestones; and 3) glauconitic-phosphatic limestones interbedded with resedimented limestones. Facies (1) forms the thinnest units whereas facies (3) is the thickest, since the thickness and spatial distribution of this facies are related to environmental contrasts caused by block faulting of the underlying carbonate platform.This lithostratigraphic unit of hemipelagic glauconite–phosphate deposition represents an interval of maximum flooding in tectonically active situations and depositional hiatus on submarine highs that separate the carbonate transgressive systems tract from the overlying terigenic tempestite highstand systems tract. This appears to be the sole condensed unit within the Miocene Manavgat Basin; and is here ascribed to a third-order (2.3) eustatic rise in sea level comprising the maximum flooding of the first-order cycle. This is also the time for early–Mid Miocene major changes in Mediterranean climate from tropical to temperate.     

浙江江山市江郎山岩石岩性特征及其对丹霞地貌形成的影响

岩性特征的量化研究对分析丹霞地貌的成因具重要意义。江郎山岩石岩性标本的X射线荧光光谱分析和偏光显微镜鉴定发现,江郎山方岩组砂岩、砾岩中SiO2含量高达55.5%-75.8%,火山岩碎屑含量高,石英晶屑多已被高温熔蚀,三爿石中多处贯穿有辉绿岩和橄榄玄武岩的岩脉和岩墙,其辉绿-间粒结构和斜长石与暗色矿物的组合,构成了抗风化能力强的岩体,使三爿石得以长期保存。洞穴岩石CaO含量百分比的平均值是崖壁的三倍,且洞穴中岩石的胶结物多为方解石,其含量超过总胶结物的50%以上,使岩石结构的稳定性受到影响,会发生类似石灰岩地区的溶蚀作用,从而导致岩体的破碎和崩塌,有可能形成诸如会仙岩、天宫洞等大型洞穴和凹槽。     

松辽盆地断陷期超层序界面的地质属性刻画及其油气地质意义

松辽盆地断陷期分为1个超层序组、3个超层序、6个层序。从火石岭组到营城组构成一个完整的活动大陆边缘火山一断陷超层序组。三个超层序分别为同碰撞期火山一断陷超层序(火石岭组)、火山间歇期断陷超层序(沙河子组)和后碰撞期火山一断陷超层序(营城组)。超层序组底界Ts界面是前三叠纪拼合基底与侏罗系火山岩一沉积岩互层序列之间的反射界面,界面上下层系之间的间断时限≥45Ma;界面之下是古亚洲洋构造域时期形成的拼合基底,界面之上是鄂霍次克洋构造域形成的火山—沉积建造。超层序组顶界T4界面是断陷期火山岩一碎屑岩互层／序列与上覆坳陷期正常沉积岩层序之间的反射界面,界面上下层系之间的间断时限为3～5Ma;界面之下是鄂霍次克洋构造域晚期形成的火山—沉积建造,界面之上是太平洋构造域早期形成的坳陷期沉积层序。层序对油气的控制作用十分明显。高产工业气藏主要见于超层序组的顶界面;工业气藏和低产气藏主要出现在层序界面附近;层序内部一般多形成低产气藏或差气层。