Terrestrial Palaeoecology and Global Change

256 Valentin A. Krassilov. Terrestrial Palaeoecology
northwestern Sakhalin (Figs. 103, 104) is exceptional in spanning all the stages, from the
Maastrichtian to the mid-Miocene, in a condensed monoclinal sequence continuously exposed
in steep coastal cliffs extending about 20 km over the Khoinjo Point. It contains the
stratotypes of several lithostratigraphic units (suites, or formations) described by Kryshtofovich
(1936), who recognized the Eocene and Miocene fossil plant assemblages. A number of
floristic horizons have been added by subsequent studies (Akhmetyev, 1978; Krassilov, 1979;
Krassilov & Kundyshev, 1982). The following analysis is based on the joint palaeofloristic and
magnetostratigraphic work by Krassilov, Schmidt and Remisovskiy (1986c).
Schematically, the Khoinjo Section includes:
(1) Cretaceous marine shales with inoceramid shells, more than 20 m.
(2) Sandstones with thin coal lenses, 4 m, unconformable on (1), containing the
Metasequoia–Trochodendroides assemblage.
(3) Conglomerates, gravels and coarse detrital sandstones (Conglomerate Formation),
about 100 m, with several floristic horizons representing the Dryophyllum–
Trochodendroides assemblage.
(4) Coarse to fine-grained sandstones, 25-30 m (Lower Member of the Lower Due
Formation), with the Magnoliaephyllum–Dryophyllum assemblage.
Fig. 103. View of the Khoindjo Secton, Cretaceous to Miocene, Tatar Straight coast of western Sakhalin
(1981).