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11.
川西须家河组前陆盆地构造层序及沉积充填响应特征 总被引:1,自引:0,他引:1
川西坳陷在须家河组沉积期为典型的周缘前陆盆地,受幕式造山运动的控制,其构造层序具有"二元体系域"的特征,即强烈造山期体系域和构造宁静期体系域。构造运动不仅控制着前陆盆地的层序地层发育,也会分配层序内部的沉积物充填。基于Vail经典层序地层学理论,综合利用地震、测录井等资料,分析研究区内构造层序类型及主控因素,阐明不同构造层序内部的沉积充填响应特征。结果表明:须家河组在前陆盆地期(须二段—须五段)可以划分为2个构造层序,其中须二段和须四段为强烈造山期体系域,须三段和须五段为构造宁静期体系域;构造运动是控制研究区构造层序发育的主要因素;强烈造山期体系域以粗粒沉积为主,发育冲积扇—辫状河三角洲—湖泊沉积体系,构造宁静期体系域以细粒沉积为主,发育曲流河三角洲—滨浅湖沉积体系。 相似文献
12.
为推进北黄海北部特色滩涂型海洋牧场建设,本研究对北黄海大鹿岛附近海域海洋牧场本底地质环境开展调查评估,利用高分辨率声学探测设备获取研究海域的精密水深数据和浅地层剖面数据;利用现场和实验室结合的方法测定海水理化参数;利用筛析法、激光粒度仪测试方法确定沉积物类型和粒度特征,最终通过分析研究区海底地形地貌、海水水质状况和沉积物分布特征对本底地质环境进行评估。结果显示:目标海域测量水深为1-29 m,平均水深为16 m,海底地形整体表现为平缓的近岸缓坡,地貌以水下侵蚀堆积地貌为主;海底浅地层剖面中U1声学地层清晰连续,全区可追踪,厚度约6 m且变化不大;海水水质良好,主要处于Ⅱ类海水水质标准;表层沉积物类型均为砂,沉积物组分变化不大,砂组分占绝对优势,表层沉积物空间分布主要与沉积物物源条件及辽南沿岸流、海域潮流等因素有关。综合分析认为,北黄海大鹿岛附近海域水深适宜,地形较为平坦,水质环境良好,以砂质浅滩沉积为主,适于滩涂型海洋牧场的构建。 相似文献
13.
李效文 《贵州师范大学学报(社会科学版)》2011,(5):82-85
在红色题材影视创作的书写系统中,贵州被加工成梦幻奇观、英雄神话的空间固然能够为受众提供某种程度上的观赏性消费满足,但是,决不应该让视听文本里的"西部空间"失去自治性、多样性的可能去受控于市场操作的过程;贵州不应是一个从现实中被抽离出来并放置到梦幻和神话表意系统中的、抽象的、空洞的符号,而应是一个建立在现实地理空间基础上的、具有区域特征和民族文化特色的、历史与现实相生的人文系统。 相似文献
14.
A taxonomic review of three Asian species of Hesperonoe (Annelida: Polynoidae) is presented. Hesperonoe hwanghaiensis Uschakov and Wu, 1959 (type locality: Qingdao, China) is redescribed based on five specimens collected from an intertidal site in the Korean coast of the Yellow Sea, as a new record of this species from Korea, which is the only known habitat outside the type locality. Hesperonoe coreensis sp. nov. is described based on nine specimens collected from two intertidal sites in the Korean coast of the Yellow Sea, including the same site as the habitat of H. hwanghaiensis. Hesperonoe japonensis sp. nov. is described by re-examination of many specimens collected from eight intertidal sites and a subtidal one in Japan, which was previously misidentified as H. hwanghaiensis. The three species are clearly distinguishable from one another by the species-specific morphology of the macrotubercles (or marked ridges) on the surface of elytra. All of the three species seemed to be commensal with the burrowing mud shrimp Upogebia major in intertidal flats, except for an additional probable host of another upogebid shrimp Austinogebia narutensis for H. japonensis sp. nov. in a subtidal habitat. The morphological characteristics and host species of the three Asian species are compared with all of the other five congeners known from the North American Pacific and Arctic Sea.http://www.zoobank.org/urn:lsid:zoobank.org:pub:51CB5C5B-0838-48AC-A0BA-8E63AA7628CB 相似文献
15.
《Journal of Natural History》2012,46(23):2109-2123
Three new species of marine nematodes belonging to the genera Paranticoma (family Anticomidae) and Parodontophora (family Axonolaimidae) are described from the Bohai Sea and Yellow Sea. Paranticoma tricerviseta sp. nov. is similar to P. bandaenseMicoletzky and Kreis, in the spicules, but can be distinguished by the presence of a ventral projection on the spicules, three regularly arranged cervical setae in both the male and female, and two distinct ventral setae behind the anus. Parodontophora deltensis sp. nov. is close to P. paragranulifera (Timm, ) in the length of the amphids, with the ventral arm of the amphid extending past the base of the stoma, but can be separated by the ratio of dorsal arm length to ventral arm (0.36–0.55 versus 0.20–0.25) and the position of the excretory pore (at the middle level versus top level of the stoma), distinctive cervical setae arrangement and a longer renette cell. Parodontophora wuleidaowanensis sp. nov. is close to P. danker Belogurov and Kartavtseva, in the form of the amphids, but can be distinguished by the longer length of the ventral arm of the amphids and the distinctive arrangement of cervical setae. 相似文献
16.
17.
《Journal of Natural History》2012,46(37-38):2255-2272
Two new species of asterocherid associated with sponges are described from the Mediterranean Sea. They are Psilomyzon laetitiae sp. nov. and Psilomyzon sarcotragusicola sp. nov. The genus Psilomyzon consists of only one known species, P. pauciseta. The two new species can be easily distinguished from the cogener species by reduction of the endopod of leg 4. In P. pauciseta the leg 4 endopod is 3-segmented, with the third segment reduced; in both new species it is 2-segmented, with the second segment carrying an inner projection, possibly homologous to the third segment of the leg 4 endopod of P. pauciseta. In the two new species, the bifid outer process on male leg 4 second endopodal segment seems to be serially homologous to the similar processes on the same segment in legs 1–3, whereas the inner projection may represent a vestigial element of the third endopodal segment of leg 4.http://zoobank.org/urn:lsid:zoobank.org:pub:33BF0653-BBA9-426B-B365-5D8C62DFD44A 相似文献
18.
《Journal of Natural History》2012,46(35-36):2243-2245
ABSTRACTThe present study describes two new genera, six new species and three new records from the Sea of Marmara. The new genus Marmara gen. nov. belonging to the family Sagartiidae is mainly characterized by having conspicuous muscular belts along the column and the absence of suckers and tenaculi on the body wall. The genus Charisactis gen. nov. belonging to the family Condylanthidae is mainly characterized by having an atypical mesentery arrangement, single siphonoglyph and homotrichs in tentacles. The other species newly described from the Sea of Marmara belong to the families Diadumenidae (one species from deep waters), Halcampoididae (one species from shallow waters), Edwardsiidae (one species from shallow waters) and Epizoanthidae (one species from deep waters). Three species, namely Epizoanthus arenaceus (family Epizoanthidae), Rolandia coralloides (family Clavulariidae) and Virgularia sp. (family Virgulariidae) are reported for the first time from the Sea of Marmara. The external and internal anatomical features as well as cnidom structures of the species are presented and discussed with the closely related species. http://www.zoobank.org/urn:lsid:zoobank.org:pub:51DA9869-D786-4A8A-8C1F-62DC1BB67923 相似文献
19.
《Journal of Natural History》2012,46(7-8):413-428
The status of Sillago erythraea Cuvier in Cuvier and Valenciennes 1829 is re-examined. A lectotype designation by McKay in 1985 fixes it as a junior synonym of Sillago sihama (Forsskål in Niebuhr, 1775), which is restricted to the southern Red Sea. Northern Red Sea populations previously assigned to S. sihama or S. erythraea, are here described as Sillago suezensis sp. nov. Sillago suezensis is also distributed in the eastern Mediterranean Sea due to Lessepsian immigration through the Suez Canal. The new species is characterized within the Sillago sihama group, which has the swimbladder divided posteriorly into two tapering extensions projecting below the vertebral column extending into the tail musculature, by the absence of scales on the preopercle and on most of the opercle, a total number of 34 vertebrae, the swimbladder with lateral extensions each spreading a blind tubule anterolaterally, and a low position of the nostril.http://www.zoobank.org/urn:lsid:zoobank.org:act:B289CDF4-AE82-44D3-9AE1-4A2B514AD348 相似文献
20.
《Journal of Natural History》2012,46(17):2145-2152
During a recent biological investigation of submarine caves of Grand Cayman, the Caribbean Sea, two species of Heteromysoides were collected. One species, referred to Heteromysoides spongicola B?cescu, 1968, is known only by the type specimens; therefore, this discovery marks the second record of occurrence and a new habitat record for the species. The other species is considered new and is described as H. stenoura, a 10th species of the genus. The new species closely resembles H. simplex Hanamura and Kase, 2001, known from the submarine caves of Okinawa, north-western Pacific, in the possession of a spiniform process on the eyes and a simple termination to the third thoracic endopod. However, the new species can be readily distinguished from the Pacific congener by a distally narrow telson and a more developed cornea in the eyes. 相似文献