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Oluwasinaayomi Faith Kasim Olayide Josiah Omirin Daniel Izuchukwu Okoro 《GeoJournal》2018,83(1):137-151
Cohabitation, as a form of sexual relationship, is becoming popular among tertiary students in developing countries. This is largely due to emergence of sexual liberalization that projects premarital sex as acceptable societal norm. The paper analyses the spatial pattern of cohabitation in communities abutting tertiary institutions in Ibadan, Nigeria. Snowball sampling technique was used to identify cohabiters at Agbowo and Apete and the Coordinates of their residence were taken using Global Positioning System. Nearest Neighbour Analysis (NNA) was adopted for spatial analysis. Spatial pattern of cohabitation at Agbowo (NNA value 1.072615) shows a random pattern. The pattern at Apete (NNA value 0.802374) displays a cluster pattern. Finding identifies, ownership, use and types of building; inadequate on-campus accommodation; peer pressure and poverty as cohabitation causal factors influencing the observed spatial patterns. Therefore, parents and guardians should adopt high-investment strategy in safeguarding the welfare and wellbeing of their wards. 相似文献
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The Cassiopeia A supernova remnant will be observed by Chandra for 1 Ms this spring. We discuss our motivations and plans
for acquiring and analyzing these data. 相似文献
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Outcrop-based sequence stratigraphic analysis and palynological biofacies were used to define depositional sequences and their bounding surfaces, and build a sequence stratigraphic model for the Upper Cretaceous succession of the Afikpo Sub-basin. Four unconformity-bounded third-order depositional sequences were identified. Sequence 1 comprises the Nkporo Formation and is subdivided into lowstand system tract (LST) representing an incised valley fill and transgressive systems tract (TST) consisting of estuarine and marine shales and mudstones. The base of the sequence is an angular unconformity correlated to the 77.5 Ma sequence boundary (SB) and the maximum flooding surface (MFS) is dated at 76 Ma. Sequence 2 is diachronous and straddles the lithostratigraphic boundary of the Nkporo and Mamu formations. The upper SB is dated at 71 Ma while associated MFS is dated at 73.5 Ma. Sequence 3 consists of the upper Mamu Formation and the Ajali Formation. The upper SB of sequence 3 is at 68 Ma while the MFS is dated at 69.8 Ma. Sequence 4 is the topmost depositional sequence belonging to the Nsukka Formation. The upper SB is placed at 66.5 Ma. The MFS within this sequence is dated at 67.8 Ma. The sequences encompass from tidally influenced bay head delta and central estuarine environments to coastal and shallow marine shelf environments. Stratigraphic architecture and facies types show that sequence development was controlled to a great extent by eustatic sea level variations though differential subsidence rates encouraged differential rates of sediment supply and rates of sea level change along different segments of the shoreline. 相似文献
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