Pes shape variation in an ornithopod dinosaur trackway (Lower Cretaceous,NW Spain): New evidence of an antalgic gait in the fossil track record

Trackways can provide unique insight to animals locomotion through quantitative analysis of variation in track morphology. Long trackways additionally permit the study of trackmaker foot anatomy, providing more insight on limb kinematics. In this paper we have restudied the extensive tracksite at Barranco de La Canal-1 (Lower Cretaceous, La Rioja, NW Spain) focussing on a 25-m-long dinosaur (ornithopod) trackway that was noted by an earlier study (Casanovas et al., 1995; Pérez-Lorente, 2003) to display an irregular pace pattern. This asymmetric gait has been quantified and photogrammetric models undertaken for each track, thus revealing distinct differences between the right and the left tracks, particularly in the relative position of the lateral digits II–IV with respect to the central digit III. Given that the substrate at this site is homogenous, the consistent repetition of the collected morphological data suggests that differences recorded between the right and the left tracks can be linked to the foot anatomy, but more interestingly, to an injury or pathology on left digit II. We suggest that the abnormal condition registered in digit II impression of the left pes can be linked to the statistically significant limping behaviour of the trackmaker. Furthermore, the abnormal condition registered did not affect the dinosaur's speed.     

A new gigantic lacewing species (Insecta: Neuroptera) from the Lower Cretaceous of Brazil confirms the occurrence of Kalligrammatidae in the Americas

Makarkinia kerneri sp. nov. is described from the Lower Cretaceous Crato Formation of Brazil, based on an incomplete but very well-preserved hind wing (Neuroptera: Kalligrammatidae). The previously presumed attribution of the genus is confirmed, based on the diagnostic characters of its wing venation (e.g., dense crossvenation; the anteriorly directed branches of MP) and the presence of a distinct eye-spot on the wing. Makarkinia is the only American representative and youngest known genus of Kalligrammatidae. With an estimated wing length of 100–160 mm, it has the largest wings amongst all fossil and extant Neuroptera.     

松辽盆地榆树林油田下白垩统泉头组扶余油层浅水三角洲沉积特征及其演化

松辽盆地榆树林油田下白垩统泉头组四段扶余油层沉积时期发育大型浅水三角洲沉积。本文基于12 口探井岩心与
2268 口钻井资料,通过单井岩心相分析、测井相分析、连井相对比和平面沉积微相研究,认为研究区发育浅水三角洲平原、
内前缘、外前缘和前三角洲亚相,以浅水三角洲平原亚相为主,平原分流河道和内前缘水下分流河道为主要沉积微相。在
扶三段（F Ⅲ）早期,研究区主要为浅水三角洲内前缘亚相,物源只来自北部 ;其后,三角洲向南进积,全区变为平原亚
相 ;F Ⅲ 3 小层沉积时期,南部物源进入,并与北部物源交汇,一直持续至扶一段（F Ⅰ）末期;在 F Ⅰ 3 小层沉积末期,湖
平面快速上升,南北两个三角洲退积,研究区中部依次出现浅水三角洲内前缘、外前缘和前三角洲。     

阿尔金北缘喀腊大湾地区早古生代中酸性火山熔岩岩石地球化学特征及其构造环境

阿尔金北缘喀腊大湾地区早古生代的中酸性火山岩为一套英安岩—流纹岩—粗面英安岩(少量)组合,在岩石地球化学上高SiO2、富碱(Na2O/K2O =0.4 ～22.2,Na2O+ K2O =2.49％ ～9.74％)、低钛,里特曼指数(δ)为0.20～5.52,铝饱和指数A/CNK为0.8～1.4,指示这是一套低钾—中钾钙碱性—碱性钾玄质(少量)火山岩,自北向南具有从准铝质Ⅰ型向弱过铝质—强过铝质S型花岗质岩浆过渡的特征.LREE、K、Ba、Th(U)、Pb、Zr富集以及Nb(Ta)、P、Ti的亏损指示其形成于与俯冲消减作用有关的活动大陆边缘环境.岩石地球化学研究表明,英安岩和流纹岩不存在分异演化关系,其源岩分别为变质(基性)火山岩和变质泥质岩.结合区域地质特征,认为该套中酸性火山岩形成于活动大陆边缘洋壳俯冲消减后期同碰撞—碰撞后的环境,是俯冲碰撞过程中陆壳巨量增厚,碰撞后伸展阶段中下地壳(或岩石圈)拆沉,幔源岩浆底侵,诱发趋于成熟的大陆边缘弧地壳在不同深度位置上发生部分熔融的产物.这一地质过程是对同一时期阿尔金北缘地区古大洋自北向南俯冲消减到米兰—金雁山地块之下的动力学机制的响应,也为判断阿尔金北缘红柳沟—拉配泉地区蛇绿混杂岩带早古生代的俯冲极性提供了佐证.     

The earthquake foci and deep structure of the Earth’s crust and upper mantle along the southern Sakhalin-Sea of Okhotsk-Kamchatka profile

The Kuril-Kamchatka seismofocal zone was thought to be a single plate approximately 90 km wide and dipping to a depth of 700 km at an angle of 40°–45°. This concept reflects primarily the physical differences (elastic wave velocities, density, temperature, etc.) between the seismofocal zone and the mantle hosting it. Detailed investigations show that the seismofocal zone proper is also heterogeneous with earthquake hypocenters variably concentrated and clustered within this zone, where both seismogenic and aseismic strata, as well as subvertical zones, can be identified. The latter are reflected in the structure and faults of the Earth’s crust and upper mantle.     

浙江中部芙蓉山花岗斑岩及包体岩石地球化学研究

花岗岩的源区、温压条件及与其他岩石的共生组合的研究可以限定其形成构造背景,了解其形成的深部动力学过程.本文对浙江中部中生代芙蓉山花岗斑岩及其暗色包体开展了全岩主微量元素、锆石U-Pb年代学和Hf同位素、Ti温度计和全岩Sr—Nd同位素研究,探讨芙蓉山花岗斑岩的成因类型、源区特征及其与镁铁质包体之间的关系,并进一步限定其...     

塔里木盆地北部坳陷震旦纪-奥陶纪大陆裂谷性质及其演化

塔里木盆地北部坳陷是在前震旦纪结晶基底之上发育起来的大陆裂谷盆地,始于早震旦世,结束于晚奥陶世.裂谷的轴部自西向东由阿瓦提凹陷、满加尔凹陷、英吉苏凹陷(包括库鲁克塔格南区)组成,向东延伸到罗布泊以东地区.裂谷轴部与地幔隆起带和高磁异常带相对应.裂谷东部主要以半深海-深海相的浊积岩、放射虫硅质岩和笔石页岩为特征,裂谷西部和翼部则以浅水盆地相和台地相的碳酸盐为特征.裂谷早期的火山岩主要分布于中东部的切谷内,具有双峰式火山岩的特征,玄武岩属低硅高钛富碱型.据区域动力学背景、沉积特征、沉降速率,将裂谷演化划分为幼年期,成年期和衰亡期3个阶段.     

Late Triassic volcanic activity in South-East Asia: New stratigraphical,geochronological and paleontological evidence from the Luang Prabang Basin (Laos)

In South-East Asia, sedimentary basins displaying continental Permian and Triassic deposits have been poorly studied. Among these, the Luang Prabang Basin (North Laos) represents a potential key target to constrain the stratigraphic and structural evolutions of South-East Asia. A combined approach involving sedimentology, palaeontology, geochronology and structural analysis, was thus implemented to study the basin. It resulted in a new geological map, in defining new formations, and in proposing a complete revision of the Late Permian to Triassic stratigraphic succession as well as of the structural organization of the basin. Radiometric ages are used to discuss the synchronism of volcanic activity and sedimentation.The Luang Prabang Basin consists of an asymmetric NE-SW syncline with NE-SW thrusts, located at the contact between Late Permian and Late Triassic deposits. The potential stratigraphic gap at the Permian–Triassic boundary is therefore masked by deformation in the basin. The Late Triassic volcaniclastic continental deposits are representative of alluvial plain and fluvial environments. The basin was fed by several sources, varying from volcanic, carbonated to silicic (non-volcanic). U–Pb dating of euhedral zircon grains provided maximum sedimentation ages. The stratigraphic vertical succession of these ages, from ca. 225, ca. 220 to ca. 216 Ma, indicates that a long lasting volcanism was active during sedimentation and illustrates significant variations in sediment preservation rates in continental environments (from ∼100 m/Ma to ∼3 m/Ma). Anhedral inherited zircon grains gave older ages. A large number of them, at ca. 1870 Ma, imply the reworking of a Proterozoic basement and/or of sediments containing fragments of such a basement. In addition, the Late Triassic (Carnian to Norian) sediments yielded to a new dicynodont skull, attributed to the Kannemeyeriiform group family, from layers dated in between ∼225 and ∼221 Ma (Carnian).     

南堡凹陷下古生界流体包裹体特征及成藏期研究

通过流体包裹体的透射光和荧光镜下观察、包裹体均一温度测定,对南堡凹陷下古生界碳酸盐岩流体包裹体特征及油气成藏期进行了研究。结果表明:南堡凹陷下古生界碳酸盐岩储层流体包裹体较为发育,主要在碳酸盐岩脉中沿愈合裂缝呈带状分布,烃类包裹体在荧光下呈黄白色--蓝白色,说明研究区油气成熟度相对较高;由包裹体均一温度实测结果可知,该区包裹体均一温度具有明显的双峰特征,峰值分别为70℃~80℃和130℃~140℃;结合埋藏史和热演化史进行综合研究,认为研究区下古生界碳酸盐岩储层主要经历了两期油气充注,第一期为25~22 Ma(东营末期—馆陶早期),第二期为8~5 Ma(明化镇中期)。