无人机遥感技术在江苏海域和海岛动态监视监测中的应用研究

本文介绍了传统海域动态监视监测存在的问题,分析了无人机遥感系统在海域动态监视监测中的应用优势,提出将我省海域无人机在海域和海岛监视监测中应用解决方案,同时对该系统在海洋其他领域中的应用前景进行了展望.     

"三江"北段昌都陆块晚三叠世钾质-超钾质火山岩成因及地质意义

昌都微陆块内部发育一套晚三叠世粗安岩.本文基于系统的野外踏勘,对具有代表性的火山岩进行岩石学、地球化学等研究.结果显示该区火山岩的SiO₂含量为51.36%~58.04%,全碱含量(Na₂O+K₂O)为5.03%~7.84%,根据岩石K₂O,MgO及K₂O/Na₂O比值判断,属钾质-超钾质火山岩,具高K、高Al、低Ti的特征.本区岩石强烈富集大离子亲石元素(LILE)和轻稀土元素(LREE),Nb、Ta、Ti的负异常明显,整体特征类似于弧火山岩.其稀土总量较高(270×10^-6~960×10^-6),轻重稀土分馏明显,重稀土分布形态较平缓.岩石具有较高的初始锶同位素比值(⁸⁷Sr/⁸⁶Sr)_i=0.7150~0.7176和较低的初始钕同位素比值(¹⁴³Nd/¹⁴⁴Nd)_i=0.51180~0.51184,ε_Nd(t)=-10.9~-10.2,二段Nd模式年龄为t_2DM=1.82~1.88Ga.本区岩石的地球化学特征显示其源区是由俯冲板片所产生的流体/熔体交代的岩石圈地幔,源区矿物组成分析结果显示,其源区以尖晶石二辉橄榄岩为主,含少量石榴石二辉橄榄岩及金云母.本区钾质-超钾质岩石虽然与西藏南部的钾质-超钾质岩石有相似的地球化学特征,但却产于碰撞后的构造背景之下.结合其所具有的弧火山岩特征及时代构造背景判断其为一种"滞后型"弧火山岩,其形成过程可以概括为三个阶段.     

西天山巨型金铜铅锌成矿带构造成矿演化和找矿方向

西天山产有Muruntau、Kumtor、Kalmakyr等巨型金矿床和Kalmakyr、Dal'neye等世界级铜矿床以及Tekeli等超大型铅锌矿床,构成世人瞩目的巨型金铜铅锌成矿带.新疆西天山金、铜、铅锌矿找矿面临重大突破,不断认识乌兹别克斯坦—吉尔吉斯斯坦—哈萨克斯坦东南部—中国新疆西部整个西天山的构造成矿过程,明确新疆西天山金、铜、铅锌矿重大找矿突破方向,预测大型矿集区十分必要.本文通过境内外野外地质矿产广泛调研和对相关文献综合研究,认为西天山造山带形成演化经历前寒武纪古陆边缘裂陷盆地、古生代洋-陆俯冲增生、晚古生代陆-陆碰撞造山、中—新生代坳陷盆地四个主要地质过程,造就出四类重要成矿系统和类型:①元古宙边缘裂陷盆地铅锌成矿系统SEDEX型;②古生代俯冲岛弧金铜铅锌成矿系统斑岩-矽卡岩-浅成低温热液型;③晚古生代碰撞造山金铅锌成矿系统造山型-MVT;④中—新生代坳陷盆地铅锌铜成矿系统砂岩型.综合对比西天山境内外成矿系统地质发育特点,预测新疆西天山那拉提-额尔宾中天山隆起带是造山型金矿找矿重大突破区,吐拉苏盆地和巴音布鲁克中天山以及那拉提山北坡有望实现斑岩型金铜找矿突破,伊犁地块南缘元古宇SEDEX型铅锌找矿值得关注,山间/山前盆地无疑是砂岩型铅锌铜找矿优先选择.     

六盘山弧形构造带铜多金属矿床的成矿环境

六盘山弧形构造带位于青藏高原东北缘,自震旦-寒武纪以来,经历了"威尔逊旋回"构造演化.在陆内裂谷和板块俯冲阶段,成矿类型主要为海底火山块状硫化物型和与韧性剪切作用有关的构造蚀变岩型,而在碰撞造山和陆内造山阶段,成矿类型演变为与大型推覆体构造有关的似层状热液型,显示出不同构造演化阶段所反映的成矿环境不同.     

Characteristics of air flow over Andaman islands including precipitation

The characteristics of simulated air flow over Andaman Islands are studied with a two-dimensional version of the University of Virginia meso scale model (UVMM). Using the observed synoptic data as initial conditions, 24 hr simulations are obtained for a day each in April and November. These days are chosen to study the variations in the simulated flow pattern under different synoptic conditions including precipitation effects. A large scale condensation scheme is employed to consider the effect of latent heat release on the perturbations. The results show that the latent heat released by condensation strengthens the intensity of perturbations and the topography accelerates the arrival of sea breeze by about an hour. The model-simulated results, given in graphical form, are discussed and compared with available observations.     

Gold Deposits in the Sanandaj–Sirjan Zone: Orogenic Gold Deposits or Intrusion‐Related Gold Systems?

Most of the known large gold deposits in Iran are located along the Sanandaj–Sirjan Zone, western Iran, which hosts a wide range of gold deposit types. Gold deposits in the belt, hosted in upper Paleozoic to upper Mesozoic volcano‐sedimentary sequences of lower greenschist to lower amphibolite metamorphic grade, appear to represent mainly orogenic and intrusion‐related gold deposit types. The largest resource occurs at Muteh, with smaller deposits/occurrences at Zartorosht, Qolqoleh, Kervian, Qabaqloujeh, Kharapeh, and Astaneh. Although a major part of the gold deposits in the Sanandaj–Sirjan Zone are related to metamorphic devolatilization, some deposits including Muteh and Astaneh are related to short‐lived disruptions in an extensional tectonic regime and are associated with magma generation and emplacement. The age of gold ore formation in the orogenic gold deposits is Late Cretaceous to Tertiary, reflecting peak‐metamorphism during regional Cretaceous–Paleocene convergence and compression. The Oligocene to Pliocene age of most intrusion‐related gold systems is consistent with the young structural setting of the gold ore bodies; these deposits are sequestered along normal faults, correlated with Middle to Late Tertiary extensional tectonic events. This relationship is comparable to the magmatic‐metallogenetic evolution of the Urumieh‐Dokhtar magmatic arc, where the number of different types of gold‐copper deposits and the magnitude of the larger ones followed development of a magmatic arc. The appropriate explanation may be related to two different stages of gold mineralization consisting of a first compressional phase during the Late Cretaceous to Early‐Middle Tertiary, which is related to orogenic gold mineralization in the Qolqoleh, Kervian, Qabaqloujeh, Kharapeh, and Zartorosht deposits, and the extensional phase during the Eocene to Pliocene that is recognized by young intrusion‐related gold mineralization in the Muteh and Astaneh deposits.     

Geochemical evidence concerning sources and petrologic evolution of Faial Island,Central Azores

Volcanic rocks that make up Faial Island, Central Azores, consist of four volcano-stratigraphic units, with ages between 730 ka and the present. Lavas range from alkali basalts to trachyandesites and belong to the alkaline-sodic series. The oldest unit is the Ribeirinha Volcanic Complex, generally characterized by low MgO contents. The Cedros Volcanic Complex is composed of basalts to benmoreites with low MgO contents. The Almoxarife Formation represents fissure flows, containing MgO contents similar to to slightly higher than those of the underlying Cedros Volcanic Complex. The youngest unit, the Capelo Formation, consists of mafic rocks with MgO values higher than those of the other units. Bulk-rock major and trace element trends suggest that differentiation of the three earliest units were dominated by fractional crystallization of plagioclase ± clinopyroxene ± olivine ± titanomagnetite. Capelo bulk-rock compositions are the most primitive, and are related to a period when volcanic activity was fed by deep magmatic chambers, and melts ascended more rapidly. Comparison among geochemical patterns of the trace elements suggests a strong similarity between the lavas from Faial and Pico islands. Corvo Island volcanism contrasts with the geochemistry of Faial and Pico lavas, reflecting its strong K and Rb depletion, and Th, U, Ta, Nb, La, and Ce enrichment. Absence of the Daly gap in the Faial volcanics is attributed to early crystallization of Ti-Fe oxides. The probable source of the Faial magma coincides with the MORB-FOZO array, which implies the presence of ancient recycled oceanic crust in the mantle source. Ratios of incompatible trace elements suggest the similarity of Corvo volcanic rocks with magmas derived from HIMU sources, whereas the Faial and Pico volcanic rocks could have been produced from sources very close to EMII-type OIB.     

海南岛西部青白口系石碌群褶皱变形特征及其控矿分析

青白口系石碌群属于一套海相沉积经变质的以细粒碎屑岩、泥岩及镁质碳酸岩夹火山岩为原岩的变质岩系组合,赋存有沉积变质型铁矿和热液型铜钴矿。岩石经历了多期次变形作用的改造,总体表现为由褶皱变形往韧脆性断裂变形演化的特征,褶皱变形包含了三个变形序列的构造形迹组合。与铁矿主成矿期密切有关的NW向石碌复向斜属于海西．印支期造山运动...     

Pliocene and late Pleistocene (MIS 5e) decapod crustaceans from Santa Maria Island (Azores Archipelago: Central Atlantic): systematics,palaeoecology and palaeobiogeography

The presence of decapod crustaceans in the Pliocene and Pleistocene (MIS 5e) fossil record of Santa Maria Island (Azores Archipelago) is herein reviewed. Our study raises the number of fossil decapods from this island from one species to 10 taxa (three for the Pliocene and seven for the Last Interglacial). Four of these 10 taxa are reported for the first time in the fossil record, worldwide. A new species of a mud shrimp is also described (Upogebia azorensis n. sp.). Our study suggests that the Plio–Pleistocene decapod assemblages of the Azores did not differ significantly from modern ones, being dominated by species that are today widespread across the Webbnesia ecoregion, the Mediterranean Sea, and the eastern Atlantic shores, including the Azores. As far as can be judged from the limited fossil record, apparently no tropical crab species with a Cabo Verdean/Senegalese provenance reached the Azores during windows of opportunity associated with Glacial Termination 2 or with the initial setting of the Last Interglacial period. This contribution increases the total number of marine taxa reported for the Pliocene and Pleistocene outcrops of Santa Maria Island to 218 and 155, respectively, highlighting the scientific relevance of its palaeontological heritage.     

滇西北永胜地区主要活动断裂与活动构造体系

位于滇西北断陷带东北部、程海-宾川断裂带北端的永胜地区上新世以来断裂活动强烈,构造地貌特征显著。永胜地区1:50000活动构造填图发现,区内共存在各类断裂14条。其中金官断裂（F₁）、永胜断裂（F₂）、木耳坪羊坪断裂（F₃）三者规模最大,活动性亦远超其他断裂,属于程海-宾川断裂带的一级分支断裂,其他断裂为程海-宾川断裂的二级分支断裂。构造地貌特征、错断地质体及擦痕统计等均指示区内断裂现今主要以伸展正断活动为主,根据活动性的差异可将其分为强、较强、中等、弱、极弱5类,其中金官断裂的活动性最强,垂向活动速率可达0.20~0.26 mm/a。对永胜地区主要断裂几何学、运动学特征的研究及动力学机制的讨论可知,永胜地区主要断裂在平面上构成向东突出的弧形旋扭构造体系,在剖面上表现为张扭性断裂常见的负花状构造;程海-宾川断裂带现今活动主要是在近南北向主压应力作用下产生的近东西向的伸展正断,并因为叠加了旋扭作用而具有一定左旋走滑。永胜地区的弧形旋扭构造体系及滇西北断陷带等均是在川滇内弧带顺时针旋转及南汀河断裂、畹町断裂与理塘断裂的走滑拉分共同作用下形成的。