scholarly journals The Geological History of Northern Central Africa

Nature ◽  
1938 ◽  
Vol 142 (3587) ◽  
pp. 220-220
1998 ◽  
Vol 25 (2) ◽  
pp. 283-291
Author(s):  
P.S.M. PHIRI ◽  
D.M. MOORE

Central Africa remained botanically unknown to the outside world up to the end of the eighteenth century. This paper provides a historical account of plant explorations in the Luangwa Valley. The first plant specimens were collected in 1897 and the last serious botanical explorations were made in 1993. During this period there have been 58 plant collectors in the Luangwa Valley with peak activity recorded in the 1960s. In 1989 1,348 species of vascular plants were described in the Luangwa Valley. More botanical collecting is needed with a view to finding new plant taxa, and also to provide a satisfactory basis for applied disciplines such as ecology, phytogeography, conservation and environmental impact assessment.


2000 ◽  
Vol 30 (3) ◽  
pp. 474-476 ◽  
Author(s):  
LUIZ JOSÉ TOMAZELLI ◽  
SÉRGIO REBELLO DILLENBURG ◽  
JORGE ALBERTO VILLWOCK

2018 ◽  
Vol 938 (8) ◽  
pp. 38-43
Author(s):  
S.A. Kotler ◽  
I.D. Zolnikov ◽  
D.V. Pchelnikov

The types of geological and geomorphological structure of the Katun valley are distinguished in the work. For this, a method of geoinformation mapping using morphometric indicators of the valley’s width and meandering of the channel was developed. The morphometric parameter of the valley’s width was calculated as the total area of terraces. As the morphometric parameters of the channel’s meandering, the angles of the river segments’ deviation relative to each other were calculated. Conjugated analysis of these morphometric indicators enabled identifying 18 morphotypes. These morphotypes according to the geological and geomorphological structure of the valley were combined into 4 classes. Separation of the Katun valley in certain classes and morphotypes is due to the different geological history of these sites during the Quaternary period. The most important reasons predetermining the modern variety of geological and geomorphological types of the valley are neotectonic movements and exogenous phenomena (glaciers, dam lakes, landslides, etc.) naturally localized in the space from the upstream of the river to its exit into the foothills. The developed method can be applied for quantitative morphometric classification of the mountain rivers’ valleys in other regions.


2016 ◽  
Author(s):  
Celine Martin ◽  
◽  
George E. Harlow ◽  
George E. Harlow ◽  
George E. Harlow ◽  
...  

Author(s):  
Brian Fagan

Ever since Roman tourists scratched graffiti on the pyramids and temples of Egypt over two thousand years ago, people have traveled far and wide seeking the great wonders of antiquity. In From Stonehenge to Samarkand, noted archaeologist and popular writer Brian Fagan offers an engaging historical account of our enduring love of ancient architecture--the irresistible impulse to visit strange lands in search of lost cities and forgotten monuments. Here is a marvelous history of archaeological tourism, with generous excerpts from the writings of the tourists themselves. Readers will find Herodotus describing the construction of Babylon; Edward Gibbon receiving inspiration for his seminal work while wandering through the ruins of the Forum in Rome; Gustave Flaubert watching the sunrise from atop the Pyramid of Cheops. We visit Easter Island with Pierre Loti, Machu Picchu with Hiram Bingham, Central Africa with David Livingstone. Fagan describes the early antiquarians, consumed with a passionate and omnivorous curiosity, pondering the mysteries of Stonehenge, but he also considers some of the less reputable figures, such as the Earl of Elgin, who sold large parts of the Parthenon to the British Museum. Finally, he discusses the changing nature of archaeological tourism, from the early romantic wanderings of the solitary figure, communing with the departed spirits of Druids or Mayans, to the cruise-ship excursions of modern times, where masses of tourists are hustled through ruins, barely aware of their surroundings. From the Holy Land to the Silk Road, the Yucatán to Angkor Wat, Fagan follows in the footsteps of the great archaeological travelers to retrieve their first written impressions in a book that will delight anyone fascinated with the landmarks of ancient civilization.


2020 ◽  
Vol 190 (2) ◽  
pp. 709-736
Author(s):  
Jae-Cheon Sohn ◽  
Shigeki Kobayashi ◽  
Yutaka Yoshiyasu

Abstract A northward trans-Wallacean radiation is demonstrated for Chrysorthenches, a member of the Orthenches group. Here we review Chrysorthenches and allied genera resulting in a generic transfer of Diathryptica callibrya to Chrysorthenches and two new congeners: C. muraseaeSohn & Kobayashisp. nov. from Japan and C. smaragdinaSohnsp. nov. from Thailand. We review morphological characters of Chrysorthenches and allied genera, and find polyphyly of Diathryptica and the association of the Orthenches-group with Glyphipterigidae. These findings were supported in a maximum likelihood phylogeny of DNA barcodes from ten yponomeutoids. We analysed 30 morphological characters for 12 species of Chrysorthenches, plus one outgroup, via a cladistic approach. The resulting cladogram redefined two pre-existing Chrysorthenches species-groups and identified one novel lineage: the C. callibrya species-group. We review the host associations between Chrysorthenches and Podocarpaceae, based on mapping the working phylogenies. Our review suggests that ancestral Chrysorthenches colonized Podocarpus and later shifted to other podocarp genera. Biogeographical patterns of Chrysorthenches show that they evolved long after the Podocarpaceae radiation. Disjunctive trans-Wallacean distribution of the C. callibrya species-group is possibly related to the tracking of their host-plants and the complicated geological history of the island-arc system connecting Australia and East Asia.


The Lake Rudolf Rift Valley Expedition was designed to carry out many different lines of investigation in the Lake Rudolf Basin. One of the chief of these was a study of the geological history of that part of the East African Rift Valley. The expedition was assisted financially by The Royal Society, The Geological Society of London, The Royal Geographical Society, The Percy Sladen Trustees and the Geographical and Geological Sections of the British Association. A general description of the activities of the Expedition was given in a paper read before the Royal Geographical Society (Fuchs 1935). Owing to the tragic loss of two members of the expedition, Dr W. S. Dyson and Mr W. R. H. Martin, two fruitless months were spent searching for them. Consequently a great amount of the work planned for the east side of the lake had to be abandoned. Nevertheless, the considerable distance travelled within the 50,000 sq. miles of the Rudolf Basin has enabled me to make out the chief events of its geological history. I am very much indebted to all those who assisted us in the field and at home, in particular to the Kenya Government, the Officers of the King’s African Rifles, and Mr H. L. Sikes of the Public Works Department; I would also like to thank Mr A. M. Champion, Provincial Commissioner of Turkana, who wholeheartedly assisted us in every way possible both in the field and at home, for he has placed at my disposal his own excellent topographical maps and his extensive observations on the geology of the area. I am also deeply indebted to Professor O. T. Jones, Mr Henry Woods and Mr W. Campbell Smith for their criticisms. Mr Campbell Smith has also given me provisional identifications of the rocks.


1977 ◽  
Vol 3 ◽  
pp. 6
Author(s):  
Bridglal Pachai ◽  
Derek Wilson
Keyword(s):  

1918 ◽  
Vol 37 ◽  
pp. 327-349 ◽  
Author(s):  
B. N. Peach ◽  
J. Horne ◽  
E. T. Newton

A characteristic feature of the plateau of Cambrian Limestone in the neighbourhood of Inchnadamff is the occurrence in it of swallow-holes, caves, and subterranean channels which are intimately associated with the geological history of the region. The valley of Allt nan Uamh (Burn of the Caves), locally known as the Coldstream Burn, furnishes striking examples of these phenomena. One of the caves in this valley yielded an interesting succession of deposits, from which were collected abundant remains of mammals and birds. The discovery of bones of the Northern Lynx, the Arctic Lemming, and the Northern Vole among these relics, and the collateral evidence of the materials forming some of these layers, seem to link the early history of this bone-cave with late glacial time, or at least with a period before the final disappearance of local glaciers in that region.


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