松辽盆地齐家地区"四史"模拟及其地质意义研究

为确定齐家地区高台子油层的油气成藏规律,应用IES petromod成藏模拟软件开展了地层埋藏史、压力演化史、成熟度演化史及油气运聚史"四史"模拟工作。地层埋藏史模拟结果表明:齐家地区经历了"3降2升"的地质埋藏过程,三个沉降期分别是:泉头组沉积末期-嫩江组沉积末期、四方台组-明水组沉积末期及依安组沉积末期-现今,两次构造抬升时期是嫩江组沉积末期、明水组沉积末期-依安组沉积末期。地层压力演化具有幕式的变化特征,青山口组二+三段地层随着埋深的增加,地层压力在嫩江组沉积末期达到峰值,后因嫩末构造运动的影响,地层压力开始减小,其后,又随着地层埋深的增加,地层压力逐渐增大,开始另一幕的形成,在明水组沉积末期,地层压力达到最大。成熟度演化史表明:嫩三段-嫩四段沉积时期,青一段烃源岩开始进入生烃门限,到明水组沉积末期,齐家-古龙凹陷一带烃源岩的镜质体反射率高达1. 0%～1. 3%,有机质成熟的范围也进一步扩大。油气运聚史表明,齐家地区高台子油层主要有嫩江组沉积末期、明水组沉积末期两次油气运聚成藏过程,其中明水组沉积末期,油气运聚范围最广,油气由生烃中心齐家-古龙凹陷向其两侧进行大规模的侧向运移聚集,形成了环凹陷周边的一系列油气藏。     

云南保山盆地的形成与演化

盆地中识别出三个不整合面,即Ｔｇ、Ｔ３和Ｔ０。其拉张史可分为两大阶段：（１）Ｔｇ→Ｔ３,拉张强度渐增期;（２）Ｔ３→现今,拉张强度渐弱期。保山盆地的演化阶段为：（１）盆地初始形成期（Ｔｇ→Ｔ５）;（２）盆地扩张定型期（Ｔ５→Ｔ１）;（３）盆地萎缩充填期（Ｔ１→现今）。     

四川省地质遗迹保护工作探讨

四川省地质遗迹资源类型丰富齐全,是不可多得的自然资源,如何保护并在“保护的前提下开发,以开发促保护,以保护促发展”,是值得探索的重大课题。     

下扬子地区热历史与海相烃源岩二次生烃潜力

下扬子地区是中国南方海相油气勘探的优选地区,针对中、古生界海相油气勘探提出了“二次生烃,晚期成藏”的部署思路。通过盆地热史恢复获得热流史,然后正演计算烃源岩成熟度史,再利用实验模拟二次生烃量版,计算区内4套主要海相烃源岩的二次生烃强度。结果表明：(1) 下扬子地区苏北、苏南、皖南地区具有不同的热演化史;(2) 二叠系和下三叠统烃源岩具有好的二次生烃潜力(150～300 mg/g),志留系烃源岩有一定的二次生烃潜力(约为120 mg/g),寒武系烃源岩几乎不具有二次生烃能力;(3) 平面上,苏南、皖南地区的二次生烃条件整体上不利,苏北各凹陷区4套海相烃源岩二次生烃强度明显大于苏南和皖南地区。     

沉积盆地热演化史研究新进展

   沉积盆地热历史及其对有机质成熟度的影响是非常活致的研究课题。本文论述了这方面的新进展，其中包括古地温研究办法、盆地热历史类型及热历史重建。作者认为恢复沉积盆地沉积热历史应重视后期地温场的改造。
        

Gold production history of the United States

Gold has played an important role in the settlement and economics of the United States. Commercial production from 24 states totaled more than 420 million troy ounces (13,000 metric tons) from 1804 through 1995. There were, no doubt, early undocumented discoveries by Native Americans, but the first records are those from the mid-1600's in the east and from the 1770's in the west. Commercial production began in 1804 in North Carolina and spread among several Appalachian states in the 1820's and 1830's as placer deposits were discovered and exploited. After peaking in the 1830's and 1840's, Appalachian production began to decline as deposits were worked out and as miners moved westward in response to the news of the discoveries in California in 1848. Appalachian production virtually ceased with the Civil War while production from California and adjacent states remained at several millions of ounces per year. As the California Gold Rush waned, new discoveries brought the Rocky Mountain states, South Dakota, and Alaska into prominence. Local, state and total production responded to time of discovery, extent of placers, labor availability, technology, government mandates and, of course, the price of gold. By 1900, the major gold rushes had occurred and most of the major producing districts were defined; however, the fixed price of gold (since 1837) provided a decreasingly attractive incentive for more exploration and exploitation. The rise in the price of gold, during the Depression provided a powerful incentive to increase gold production, but one that was cut short by War Production Board Order L-208 which closed the gold mines in 1942. In the post-war period, the fixed price, combined with the prohibition of American gold ownership, again proved to be a disincentive and gold production dropped. The era of free gold price that began in 1968, followed by the permission for Americans to again own gold, brought new interest in gold with prices rising briefly in 1980 to US$850 per ounce and remaining above US$350 per ounce through 1995. This higher price, combined with the technology for bulk mining and processing of low grade ores, provided incentive for new exploration and exploitation. Consequently, gold production soared above 10 million ounces per year in the early 1990's with 65% coming from Nevada. There has been a general decrease in the grade of gold ores since the early 1900's and significant changes in the methods of recovery. Despite the decreasing grade, the reserves of recoverable gold have more than doubled since the early 1970's.     

大别造山带北麓地区自石炭纪以来构造演化研究

大别造山带北麓地区位于大别造山带外侧缘,其构造演化过程严格受大别造山过程的控制。大别造山带北麓地区构造热史的恢复对于整个大别造山带造山过程的研究具有重要意义。造山带外缘复杂的构造演化过程,造成了其埋藏史恢复的复杂性。在综合分析该地区石炭系上覆地层分布、侵入岩中矿物结晶压力以及构造运动发展阶段等多方面资料的基础上,以全新的思路恢复了大别造山带北麓地区石炭系埋藏史,分析认为,自石炭纪以来,大别造山带北麓地区共经历了三次沉降和三次隆升的演化过程。     

冀东太古代花岗质岩石成因组构研究

我国冀东地区广泛分布着太古代各种花岗质岩石(英云闪长质—奥长花岗质—花岗质片麻岩,及微斜长石花岗岩)。在这些花岗质岩石中见有各种成因组构:残余岩浆组构、聚集重结晶组构、交代一熔蚀组构、分凝—共结组构及塑变—碎裂组构。运用这些标志性组构不仅可以研究该区花岗质岩石的成因而且可以追溯这些花岗质岩石的形成演化历史。     

中国近代银铅矿开发概貌

总结了我国清末至民国初期（１８４０－１９２０年）长达８０年的银铅矿开发概貌，按现行政区划共涉及１４个省。对各省的银铅矿．既扼要探讨历史沿革，又尽量地汇集具体产银产铅地名及有关地质矿产信息，对了解和研究近代中国银矿开发史，系统地总结现代中国银铅矿床的由来，都有一定的意义。     

Anti-Semitism in German geography 1900–1945

The number of Anti-Semitic opinions found in geographical and geopolitical literature gives evidence of a wide-spread hostility towards Jews before 1945. Only very few critical dissidents branded Anti-Semitism as propaganda of political rightists. The extent to which Anti-Semitism served as an ideological bridge between geography and geopolitics in Germany till 1945 must be established. But independent from geopolitics, there are lots of proof for an autochthonously developed Anti-Semitism among German university geographers long before geopolitics was created. All in all geopolitics had no innovative effect on the research and the theory of political geography in Germany till 1945. Its main topics, epistemological premises and methodological apparatus grew on the substratum of authochthonous traditions created in the 19th century. Geopolitics only takes up basic reflections that already exist.     

准噶尔盆地腹部油气充注与再次运移研究

准噶尔盆地为一个经历多期构造运动的叠合型盆地。盆地腹部油气藏形成与演化是一个受多源、多期次油气充注与再次调整的复杂过程。采用烃源岩生烃史正演模拟与油气藏地质、地球化学反演分析相互验证的方法,表明腹部油气运聚可以分为早期、晚期和后期油气充注,即:早白垩世前的早期原油充注阶段,原油主要来自于下二叠统风城组烃源岩;晚白垩世以原油充注为主的晚期充注阶段,原油主要来源于上二叠统下乌尔禾组烃源岩;古近纪以来以天然气充注为主的后期充注阶段,天然气来自于风城组和下乌尔禾组烃源岩高过成熟阶段的产物。受喜马拉雅构造运动的影响,形成于中晚燕山期的腹部车莫古隆起发生掀斜作用,致使油气发生再次运移,调整后的腹部油气藏呈分散和小规模分布,油气藏类型由以构造圈闭为主变成以地层/岩性圈闭为主。     

吉林桦甸市夹皮沟本区金矿剥露历史和矿床保存变化——来自磷灰石裂变径迹年代学证据

有关吉林省桦甸市夹皮沟金矿区剥露历史的研究,至今尚不多见,然而成矿后的变化与保存是矿床学研究的一个重要领域,并且矿区剥露历史对于区内矿体保存状况具有重要的指示意义。裂变径迹是研究区域隆升剥露的一种有效手段,能提供剥蚀速率和剥蚀量的定量数据,本文应用裂变径迹技术研究夹皮沟金矿区中生代成矿以来的剥露历史。使用磷灰石裂变径迹年龄数据进行热历史模拟,揭示其演变机理。实验中获得8个了磷灰石裂变径迹测试结果,裂变径迹年龄可分为3组:(128~111Ma、86~64Ma和48~29Ma)。夹皮沟金矿区的热演化历史可分为了3个阶段,分别为:第1阶段160Ma到85±10 Ma;第2阶段85±10 Ma到28±2 Ma;第3阶段28±2 Ma至今,相应的剥露深度为2.90km、0km和1.17km。根据剥露厚度及成矿深度推测,夹皮沟本区中下戏台、立山两矿区金矿床保存状况良好,下部仍有较大探矿潜力。     

The discovery and history of the Dalgaranga meteorite crater,Western Australia

The Dalgaranga meteorite crater, 100 km northeast of Yalgoo, Western Australia, was one of the first impact structures identified in Australia, the smallest isolated crater found in Australia, and the only confirmed crater in the world associated with a mesosiderite projectile. Seventeen years passed before the Dalgaranga meteorites were described in the scientific literature, and nearly 40 years passed before a survey of the structure was published. The reasons for the time gap were never explained and a number of factual errors about the discovery and early history remain uncorrected in the scientific literature. Using historical and archival documents, and discussions with people involved in Dalgaranga research, the reasons for this time gap are explained by a series of minor misidentifications and coincidences. The age of the crater has yet to be determined, but using published data, we estimate the projectile mass to be 500–1000 kg.     

青藏高原北缘山脉隆升时限的同位素证据

青藏高原北缘江尕勒萨依地区新生代地层中自生矿物的O和C同位素测试结果显示，δ^18O和δ^13C在浙新世早期和中新世早期都出现急剧的变化。沉积学特征也表明中新世早期新生代沉积物质粒度快速变大，而上新世至早第四纪沉积速率急剧加大。由此推断，青藏高原北缘山脉最早期的隆升开始于浙新世的早期；并在中新世早期出现过山脉的快速隆升；而上新世至第四纪早期山脉的隆升最为强烈。