scholarly journals The Northwest Africa (NWA) 5790 meteorite: A mesostasis-rich nakhlite with little or no Martian aqueous alteration

2015 ◽  
Vol 50 (2) ◽  
pp. 287-304 ◽  
Author(s):  
Tim Tomkinson ◽  
Martin R. Lee ◽  
Darren F. Mark ◽  
Katherine J. Dobson ◽  
Ian A. Franchi
Keyword(s):  
Aqueous Alteration ◽  
Northwest Africa

scholarly journals Aqueous alteration of the Martian meteorite Northwest Africa 817: Probing fluid-rock interaction at the nakhlite launch site

2018 ◽  
Vol 53 (11) ◽  
pp. 2395-2412 ◽  
Author(s):  
M. R. Lee ◽  
L. Daly ◽  
B. E. Cohen ◽  
L. J. Hallis ◽  
S. Griffin ◽  
...  
Keyword(s):  
Aqueous Alteration ◽  
Rock Interaction ◽  
Martian Meteorite ◽  
Northwest Africa ◽  
Launch Site

scholarly journals Aqueous alteration in the Northwest Africa 817 (NWA 817) Martian meteorite

2002 ◽  
Vol 203 (1) ◽  
pp. 431-444 ◽  
Author(s):  
Ph. Gillet ◽  
J.A. Barrat ◽  
E. Deloule ◽  
M. Wadhwa ◽  
A. Jambon ◽  
...  
Keyword(s):  
Aqueous Alteration ◽  
Martian Meteorite ◽  
Northwest Africa

LITHOLOGIC DIVERSITY WITHIN LUNAR REGOLITH BRECCIA METEORITE NORTHWEST AFRICA 8783: CLASTS 3 AND 6

2020 ◽  
Author(s):  
Cecillia Utterback ◽  
◽  
Madi Hall ◽  
Erin M. Recchuiti ◽  
Amy L. Fagan
Keyword(s):  
Lunar Regolith ◽  
Northwest Africa

scholarly journals Molecular Species Delimitation of Larks (Aves: Alaudidae), and Integrative Taxonomy of the Genus Calandrella, with the Description of a Range-Restricted African Relic Taxon

Diversity ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 428
Author(s):  
Martin Stervander ◽  
Bengt Hansson ◽  
Urban Olsson ◽  
Mark F. Hulme ◽  
Ulf Ottosson ◽  
...  
Keyword(s):  
Mitochondrial Dna ◽  
Molecular Species ◽  
Species Delimitation ◽  
Integrative Taxonomy ◽  
West African ◽  
Northwest Africa ◽  
Sub Saharan ◽  
Plateau State ◽  
Avian Family ◽  
Relic Population

Larks constitute an avian family of exceptional cryptic diversity and striking examples of convergent evolution. Therefore, traditional morphology-based taxonomy has recurrently failed to reflect evolutionary relationships. While taxonomy ideally should integrate morphology, vocalizations, behaviour, ecology, and genetics, this can be challenging for groups that span several continents including areas that are difficult to access. Here, we combine morphometrics and mitochondrial DNA to evaluate the taxonomy of Calandrella larks, with particular focus on the African C. cinerea and the Asian C. acutirostris complexes. We describe a new range-restricted West African taxon, Calandrella cinerea rufipecta ssp. nov. (type locality: Jos, Plateau State, Nigeria), with an isolated relic population 3000 km from its closest relative in the Rift Valley. We performed molecular species delimitation, employing coalescence-based multi-rate Poisson Tree Processes (mPTP) on cytochrome b sequences across 52 currently recognized lark species, including multiple taxa currently treated as subspecies. Three species-level splits were inferred within the genus Calandrella and another 13 across other genera, primarily among fragmented sub-Saharan taxa and taxa distributed from Northwest Africa to Arabia or East Africa. Previously unknown divergences date back as far as to the Miocene, indicating the presence of currently unrecognized species. However, we stress that taxonomic decisions should not be based on single datasets, such as mitochondrial DNA, although analyses of mitochondrial DNA can be a good indicator of taxa in need of further integrative taxonomic assessment.

scholarly journals The old, unique C1 chondrite Flensburg – Insight into the first processes of aqueous alteration, brecciation, and the diversity of water-bearing parent bodies and lithologies

2021 ◽  
Vol 293 ◽  
pp. 142-186
Author(s):  
Addi Bischoff ◽  
Conel M. O'D. Alexander ◽  
Jean-Alix Barrat ◽  
Christoph Burkhardt ◽  
Henner Busemann ◽  
...  
Keyword(s):  
Aqueous Alteration ◽  
Insight Into

scholarly journals Cuttlebone morphometrics and sex identification of Sepia bertheloti (d’Orbigny, 1835) from the central-east Atlantic

2019 ◽  
Vol 73 (1) ◽  
Author(s):  
Airam Guerra-Marrero ◽  
David Jiménez-Alvarado ◽  
Vicente Hernández-García ◽  
Leticia Curbelo-Muñoz ◽  
José Juan Castro-Hernández
Keyword(s):  
Morphometric Analysis ◽  
Growth Pattern ◽  
Gonadal Development ◽  
Sex Identification ◽  
East Atlantic ◽  
Subsequent Increase ◽  
Northwest Africa ◽  
Males And Females

Abstract Analysis of 322 cuttlebones of Sepia bertheloti caught in the waters of the Northwest Africa showed significant differences in growth between males and females. Morphometric analysis revealed a relatively different cuttlebone growth pattern between sexes, with males presenting faster growth in length to reach larger sizes and females displaying greater growth in width. This difference in cuttlebone growth is related to female gonadal development and the subsequent increase of the paleal cavity, providing more support and space to accommodate a higher number of oocytes.

The aqueous alteration of GEMS-like amorphous silicate in a chondritic micrometeorite by Antarctic water

2021 ◽  
Vol 293 ◽  
pp. 399-421
Author(s):  
M.D. Suttle ◽  
L. Folco ◽  
M.J. Genge ◽  
I.A. Franchi ◽  
F. Campanale ◽  
...  
Keyword(s):  
Antarctic Water ◽  
Aqueous Alteration ◽  
Amorphous Silicate

Seismic geomorphology of early North Atlantic sediment waves, offshore northwest Africa

2013 ◽  
Vol 1 (1) ◽  
pp. SA75-SA91 ◽  
Author(s):  
Dallas B. Dunlap ◽  
Lesli J. Wood ◽  
Lorena G. Moscardelli
Keyword(s):  
Seismic Survey ◽  
Entire Study ◽  
Sediment Waves ◽  
Northwest Africa ◽  
Stable Slope ◽  
Wave Forms ◽  
History Of ◽  
Wave Heights ◽  
Slope Currents ◽  
Mass Transport Deposits

The lower continental rise of Morocco’s Atlantic Margin contains three varying morphologies of buried deepwater sediment waves. The 3D mapping of a [Formula: see text] seismic survey acquired in the Safi Haute Mer seismic block revealed numerous linear features that range from small, less than 17-m-thick Jurassic-age amplitude striations up to 110-m-thick migrating Cretaceous contourite sediment waves. Early proto-Atlantic deposition in Safi Haute Mer initiated in the Triassic, with syn- and postrift accumulation in basement half-grabens basinward of the modern Moroccan salt front. Sedimentation continued through the Mesozoic with deposition of turbidites, progradation of clinoforms, and culminating in multiple Late Cretaceous, regionally expansive, mass-transport deposits ([Formula: see text]). Tertiary stratigraphy consists of multiple thin, pelagic drapes and unconformities. The complex history of sedimentation and tectonics gave rise to three styles of sediment waves found within the study area: (1) type J1 — small and poorly imaged, Jurassic age, locally generated wave forms that have wavelengths of up to 12 km and crest-to-crest separations of less than 1 km with little or no vertical expression; (2) type K1 — early Aptian constructional sediment waves ([Formula: see text] thick) built by contour currents that traveled in and near a contourite moat at the base of a seafloor high produced by shallowly buried mobile salt; and (3) type K2 — latest Albian and earliest post-Albian sediment waves built by along-slope currents on a relatively stable slope, showing evidence of updip migration. The type K2 sediment wavefield exhibits wave heights of 40 m and crest-to-crest separations of 1 km, and it is continuous over the entire study area.

Upwelling and boundary circulation off Northwest Africa as depicted by infrared and visible satellite observations

1991 ◽  
Vol 26 (4) ◽  
pp. 357-402 ◽  
Author(s):  
L. Van Camp ◽  
L. Nykjaer ◽  
E. Mittelstaedt ◽  
P. Schlittenhardt
Keyword(s):  
Satellite Observations ◽  
Northwest Africa
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