Details

Autor(en) / Beteiligte

• Schopf, James M
• Turner, Mort D
• Splettstoesser, John E

Titel

Forms and Facies of Vertebraria in Relation to Gondwana Coal

Ist Teil von

• Geology of the Central Transantarctic Mountains, 1986, p.37-62

Ort / Verlag

Washington, D. C: American Geophysical Union

Erscheinungsjahr

1986

Quelle

Wiley Online Library All Obooks

Beschreibungen/Notizen

• Evidence accumulated over 150 years suggests that the glossopterids were an isolated group of plants with some unusual features. I consider that Vertebraria , which shows anatomical features of roots, was a member of this group with a corresponding number of unusual characteristics. Study of permineralized, partly permineralized and partly coalified, and fully collapsed (coalified) small roots also suggests a basis for an environmental interpretation. Many of the associated small roots that probably belong to Vertebraria have been fossilized in situ. Collapsed tissue structure, the prevalence of sediment intrusions in air spaces within roots, and the attitude of roots in relation to bedding provide means of judging whether roots are preserved in their original place of growth. Large roots, at least 15 em in diameter, show that the Vertebraria (glossopterid) ‘trees' at least attained arborescent stature. Features of large compressed roots of Vertebraria are readily explained according to permineralized anatomy. There is little question that roots of Vertebraria type may be transported along with leaves, branches, and sedimentary debris, but environmental significance should be principally attached to roots that are in situ. The examples illustrated provide an ample means of distinguishing transported from original positions of growth. The abundant roots of Vertebraria are essentially the Gondwana equivalent of the rhizophores and roots of Stigmaria of the Arcto‐Carboniferous coal fields that have long been recognized as having environmental meaning, and the facies interpretation of Vertebraria should be similarly applied in Gondwanaland. Vertebraria was a major contributor to deposits of Gondwana coal.