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71.
Several traces of biological interaction were found on penguin bones from the basal levels (Aquitanian) of the Miocene Gaiman Formation in the lower Chubut valley of the Provincia del Chubut, Argentina. The fossil-bearing beds were deposited in littoral to sublittoral environments within sediments of mostly pyroclastic origin. We interpret many traces to have been produced by predators and/or scavengers while the penguins were still in a breeding area. Many bones show cracking marks due to aerial exposure. The material is disarticulated as is usual in recent breeding areas. Potential predators were coeval terrestrial mammals, most probably marsupial carnivores. After a marine transgression, these bones were buried or exposed on the sea bottom where they could be colonized by algae, sponges, cnidarians, and other benthic organisms. We identified sponge borings in several bones. Other traces are interpreted to have been produced by echinoderms feeding on sponges or algae. No evidence of other invertebrate predators such as muricid or naticid gastropods, or decapods was found. Finally, other traces appear to have been generated by shark and possibly teleostean vertebrates feeding on epibionts. One coracoid is interpreted to have been marked by a shark that is common in the Gaiman Formation, the carcharhiniform Galeocerdo aduncus. From an ethological (Seilacherian) classification, traces on bones from the Gaiman Formation include Domichnia (sponge perforations), Praedichnia (terrestrial marsupials, sharks, teleosteans) and Pasichnia (echinoderms). Remarkably, remains of marine organisms with skeletons made of calcium carbonate are very poorly preserved in the Gaiman Formation. Only large oysters, sparse shell fragments, skeletal moulds, and bioturbation is evident. The fossil assemblage is mainly composed of phosphatic (e.g. teeth, bones, crustacean parts) and siliceous (sponge spicules, diatoms) remains.  相似文献   
72.
Transgression is not only an inevitable part of systemic supervision but is also necessary if we are to work towards innovative and inclusive supervisory and therapeutic practice. Defying culturally generated ‘rules’ of systemic practice can allow for more relevant and productive ways of talking. Systemic practitioners are increasingly finding themselves trying to practice systemic therapy in employing authorities and training courses which are dominated by inflexible professional narratives and manualised procedures. Our profession is committed to ethical inner and outer dialogue, to self‐ and relational reflexivity as distinct from the rule‐bound surveillance culture in which we live and work. Systemic supervisors and therapists may find themselves at odds with monological institutional discourse and attempts from within our own profession to manualise practice. I introduce examples from supervisory conversations to illustrate how supervisors can develop more culturally sensitive practices through supporting practitioners to hear and have heard their own marginalised and oppressed voices and those of their clients.  相似文献   
73.
福建东南沿海第四纪盆地构造沉降   总被引:1,自引:0,他引:1       下载免费PDF全文
利用福建东南沿海地区城市活断层探测的研究资料,重新确认了福州、泉州和漳州盆地的断层组合与第四纪沉积。研究区内晚更新世“福州海侵”产生的炭质淤泥沉积现代高程的分析对比表明,晚更新世以来该区地壳发生不均匀隆升,而这些盆地相对于研究区内其他地区发生沉降。断层的静态位错理论研究认为,正断层深部活动引发地表的沉降,该区断裂的深部正断层活动是盆地沉降的重要因素。盆地的发展演化可划分为晚更新世以前的断陷阶段,和其间或其后的拗陷沉积阶段。  相似文献   
74.
The discovery of a previously unrecognized unconformity and of new faunas in the type Llandovery area underpins a revised correlation of Hirnantian strata in mid Wales. This has revealed the sedimentary and faunal events which affected the Lower Palaeozoic Welsh Basin during the global rise in sea level that followed the end‐Ordovician glacial maximum and has allowed their interpretation in the context of local and global influences. In peri‐basinal shelfal settings the onset of post‐glacial deepening is recorded by an unfossiliferous, transgressive shoreface sequence (Cwm Clyd Sandstone and Garth House formations) which rests unconformably on Rawtheyan rocks, deformed during an episode of pre‐Hirnantian tectonism. In the deep water facies of the basin centre, this same sequence boundary is now recognized as the contact between fine‐grained, re‐sedimented mudstones and an underlying regressive sequence of turbidite sandstones and conglomerates; it is at a level lower than previously cited and calls into question the established lithostratigraphy. In younger Hirnantian strata, graptolites associated with the newly recognized Ystradwalter Member (Chwefri Formation) demonstrate that this distal shelf unit correlates with the persculptus graptolite‐bearing Mottled Mudstone Member of the basinal succession. Together these members record an important macrofaunal recolonization of the Welsh Basin and mark a key event in the post‐glacial transgression. Further deepening saw the establishment of a stratified water column and the imposition of anoxic bottom water conditions across the basin floor. These post‐glacial Hirnantian events are consistent with the re‐establishment of connections between a silled Welsh Basin and the open Iapetus Ocean. However, a comparison with other areas suggests that each event records a separate deepening episode within a pulsed glacio‐eustatic transgression, while also reflecting changes in post‐glacial climate and patterns of oceanic circulation and associated biotic flux. British Geological Survey © NERC 2009. All rights reserved.  相似文献   
75.
青年农民工越轨行为的社会心理学分析   总被引:5,自引:0,他引:5  
青年农民工越轨问题影响到城市的稳定,青年农民工越轨问题的社会心理原因主要是因为社会排斥、挫折感和相对剥夺感引起的心理失衡,而处于心理失衡中的青年农民工又缺乏必要的社会支持机制,因而引起青年农民工的社会越轨问题。  相似文献   
76.
歧口凹陷古近系沙河街组一段下亚段湖盆咸化成因   总被引:3,自引:0,他引:3  
歧口凹陷沙河街组一段下亚段(简称沙一下亚段)在整体湖扩的背景下形成了多套薄层白云岩发育于暗色泥岩的特殊岩性段,显示出较强的咸化湖盆环境。对研究区内不同岩性样品进行的微量元素分析结果表明,歧口凹陷沙一下亚段主要为盐度较大的咸水环境;碳、氧稳定同位素测试显示该区碳酸盐岩δ13C 偏正异常明显,Z值分布范围为111~168.52;锶稳定同位素分布范围略高于同期海水,远低于同期河、湖水。结合薄片观察中发现的具指相意义的海绿石、胶磷矿,扫描电镜下发现的钙质超微化石研究表明,歧口凹陷沙一下亚段湖盆咸化可能是海侵所致。  相似文献   
77.
小说<塞壬娜/萨琳娜>通过描写波多黎各跨性别人的生活状况,表现了作者对于跨性别人的同情和对于性别身份的思考,解构了男性与女性二元对立的社会性别分类,并试图表明跨性别人存在的合理性.通过描写波多黎各在政治地位和文化形态上的他者形象、跨性别人存在的普遍性、种族的混杂性以及普遍的移民和流散现象,小说表明了界定和建构波多黎各民族身份的复杂性、艰巨性和必要性,批判了性别本质主义和波多黎各民族身份界定中出现的种族本质主义,探讨了建构性别身份和波多黎各民族身份新的可能性.  相似文献   
78.
The perception of behavior as a moral or conventional concern can be influenced by contextual variables, including status and power differences. We propose that social processes and in particular social role enactment through the exercise of power will psychologically motivate moralization. Punishing or rewarding others creates a moral dilemma that can be resolved by externalizing causation to incontrovertible moral rules. Legitimate power related to structure and position can carry moral weight but may not influence the power holder’s perceptions of rules and general norms of behavior. Social identity theory suggests moralization could be promoted by a concern for shared, defining values. However, the tendency to moralize another’s behavior can be injurious to shared identity. We explored white-collar employees’ perceptions of several categories of noxious or deviant workplace behaviors and regressed these perceptions on the tendency to use legitimate, referent, or reward and punish power; social identity; and the interaction of social identity and power, in particular legitimate power. Only the tendency to influence others through punishment or reward predicted moralization. Alternative causal explanations for the findings were addressed through the absence of any relationships between punishment and reward power and perceptions of deviant behaviors as wrong, upsetting, or requiring punishment. We discuss these results in the context of self and social processes, the social construction of morals and power, and the impact of managers’ behavior on group or organizational ethics.  相似文献   
79.
济阳坳陷古近系沙河街组海侵问题研究   总被引:12,自引:0,他引:12  
袁文芳  陈世悦  曾昌民 《石油学报》2006,27(4):40-44,49
从4个方面对济阳坳陷古近纪是否发生过海侵进行了论证:1盐类矿物演化序列的海相性特点;2海相遗迹化石Paleodictyon的发现;3Paleodictyon围岩中可以指示海侵发生的甲藻甾烷分子化石的发现;4有海侵证据的沙河街组沉积时期的湖进基本与全球范围的海侵吻合.研究结果表明,济阳坳陷古近纪沙河街组沉积期曾经受到过海水波及或短时期与海连通.海侵作用对研究区优质烃源岩的成因和中国东部渤海湾盆地的古地理格局以及新生代沉积盆地内的层序地层都具有重要作用.  相似文献   
80.
古生物学经历了4个发展阶段:形态古生物学阶段、古生态学阶段、古生物地理学阶段和古生物迁移研究阶段。古生物迁移研究是古生物学现代发展的必然结果。李四光教授早在20年代就注意到古生物迁移现象,并把古生物迁移资料应用于海水进退规程的研究中。到了60年代,李四光教授再次强调古生物迁移研究的重要意义。可以认为,古生物迁移,不仅是地质力学基础理论的一个极重要的研究领域,而且更是地壳运动理论和古生物学发展的一个极重要的研究课题。   相似文献   
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