The gene pool of the Belgorod oblast population: II. “Family name portraits” in groups of districts with different degrees of subdivision and the role of migrations in their formation
AbstractThe frequencies and spectra of surnames have been analyzed in groups of raions (districts) of the Belgorod oblast (region) with different degrees of population subdivision. The “family name portraits” of districts with low (0.00003 < < f*r < 0.00022, 
$$\overline {f_r^ * } $$
 = 0.00015) and moderate (0.00023 < f*r < 0.00042, 
$$\overline {f_r^ * } $$
 = 0.00029) inbreeding levels are similar both to each other and to the “family name portrait” of the Belgorod oblast as a whole. Districts with high subdivision levels (0.00043 < f*r < 0.00125, 
$$\overline {f_r^ * } $$
 = 0.00072) had very distinctive surname spectra and the highest surname frequencies. Intense immigration to the Belgorod oblast significantly affects its population genetic structure, decreasing the population subdivision.
Population-Genetic Structure of the Residents of Central Russia
In the territory of Central Russia, the presence of a certain, ordered system of grouping of elementary populations (raions) has been established, according to the data on the frequencies of surnames, using various methods of multivariate statistics (cluster analysis, multidimensional scaling, factor analysis). All the raions of the Belgorod oblast are combined into four clusters, corresponding to real geographical location of the populations: central cluster (12 raions), western (4 raions), south-eastern (3 raions), eastern (2 raions). Geographical distances between them play a significant role in the formation of genetic division between elementary populations.
Correlation of the Upper Cretaceous White Chalk (Turonian to Campanian) in the Anglo-Paris Basin
Using key lithological, biostratigraphic and geophysical borehole-log markers a correlation of the Upper Cretaceous Chalk stratigraphies across the whole Anglo-Paris Basin has been achieved. A common lithological marker bed stratigraphy applies and key fossil markers (inoceramids, Micraster and Echinocorys ) are consistently related to the same lithological markers throughout the basin. The major lithological changes consistently occur at the same levels but are not necessarily equally strongly developed. The magnificent dip section along the French Channel coast between the Somme and the Seine, and the inland sections at Precy-sur-Oise and Verlin (Loiret) illustrate the influence of long-lived tectonic lines on Chalk sedimentation history recognised by: (i) rapid thickness variations; (ii) channel flooring hardgrounds and associated anomalous bedding dips: (iii) stratigraphically anomalous infills of channels which may be metres to kilometres across; (iv) redeposited chalks containing abundant Bathichnus paramoudrae ; (v) tectonically induced slumps and slides with flint and chalk shatter beds (palaeoseismic horizons). These features are found along may axes including the Anticlinal du Bray at Precy and Dieppe, the Anticlinal de Margny-les-Compiegne at Nourard le-Franc and Le Treport (the Bresle Valley Axis) and the Fecamp and Verlin fault systems. The ‘events’ recognised along these axes link with similar events recognised in Sussex (e.g. Kingston Anticline), on Portsdown, at Culver Cliff, Isle of Wight (Sandown Pericline) and on the Weymouth Anticline (White Nothe). Such events are common in the high Turonian, low Coniacian, basal Santonian, and the low and mid Campanian. The recurrence of key marker beds dominated by a particular trace fossil association or sequence, Bathichnus-Thalassinoides suevicus-Zoophycos associated with major changes in lithology, micro and macro-fauna indicates more widespread ‘oceanographic’ cycles of transgression and regression related to Atlantic opening.