The Russian Carboniferous and Permian compared with those of India and America : a review and discussion / by Charles Schuchert.
- Charles Schuchert
- Date:
- 1906
Licence: In copyright
Credit: The Russian Carboniferous and Permian compared with those of India and America : a review and discussion / by Charles Schuchert. Source: Wellcome Collection.
Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.
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![lower horizons. Should the detailed examination show that the fossils of the various horizons of the Productus limestone are also found associated in the thin fossiliferous zone of the Belleroplion limestone of Ivrain, the conclusion will be una- voidable that the various zones of the Productus limestone are of Upper Permian age.” In the second paper cited above, treating of the fauna of the Productus shales, Diener states the following “The only decisive evidence for a permian age of the Pro- ductus shales is however based on their stratigraphical rela- tions to the triassic beds of the mesozoic belt of the Central Himalayas, not on their fossil remains. One of the chief results of Griesbach’s geological survey of the Phot Mahals of Kumaon and Gurhwal is the proof of an unconformity, exist- ing at the base of the Productus shales, which locally overlap successive strata of carboniferous age. With this unconform- ity another uninterrupted sequence begins, with conformable bedding throughout, which ranges from the Productus shales to the topmost beds of the triassic system. So intimate is the stratigraphical connection between the Productus shales and the following Otoceras beds of lowest triassic age, that a sharp boundary cannot be drawn between them ” (pp. 53-54). In the third publication above cited, Diener reviews his for- mer work on the fossils of Chitichun No. 1, owing to larger and more significant collections subsequently made by Walker. These collections have not altered Diener’s correlations with the Salt Range, but they have, when interpreted in the light of Noetling’s publications, caused him to depart strongly from the nearly unanimous views of European stratigraphers and to agree in the main with the intercontinental correlation of Noetling. Great weight should be attached to the correlation of these two paleontologists, for they have collected the fossils of the Permian in India and studied them in the laboratory. Diener’s conclusions are as follows :— “ So far there is no reason for any change in my correlation of the Chitichun fauna with Indian faunae of petmian age, as proposed by myself in 1897. I am, however, bound to confess that the affinities of the Chitichun fauna to those of Europe have not been correctly interpreted, and that my examination of Walker’s materials is apt to lead in this respect to results remarkably different to those deduced in my first memoir. “ In that memoir [here numbered 1] the conclusions at which I arrived with regard to the stratigraphical position of the Chitichun fauna were summed up as follows:— “ ‘ The Chitichun limestone is approximately homotaxial with the upper division of the middle Productus limestone (Virgal and Kalabagh beds) in the Salt Range. It probably corresponds in age to the pernio-carboniferous horizon (Artin-](https://iiif.wellcomecollection.org/image/b22407194_0028.jp2/full/800%2C/0/default.jpg)
