摘要:

Formal Chronostratigraphic Units are defined in theInternational Stratigraphic Guideon the basis of boundary stratotypes and then extended globally as isochronous units. They are unrealistic for application to late‐Quaternary history, which involves events that are demonstrably time‐transgressive owing to measurable lags between the causative force and the geologic response. Natural geologic time units that are diachronous globally are preferred because they represent events identifiable in the stratigraphic record. A similar objection is raised against formal Chronostratigraphy for the pre‐Quaternary: recognizable biostratigraphic or lithostratigraphic units on which the geologic time scale has been built are diachronous globally, for they depend on slow evolutionary or tectonic processes. The imposition of Chronostratigraphic Units that are unrecognizable stratigraphically at a distance away from the type locality introduces an unnecessary terminology in the efforts of stratigraphers to econstruct the geologic hi

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1980.tb01038.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

A thin mantle of cover‐loam over much of North‐East Essex has been recognised as consisting largely of loess. The cover‐loam represents the intermixing, to a varying degree, of a layer of loessial silt with a thin layer of underlying sand which is also of likely aeolian origin. The heavy mineral content of the coarse silt fraction of North‐East Essex loess is generally similar to that of last glaciation age loesses elsewhere in Eastern England, Belgium and the Netherlands. This suggests the North‐East Essex loess is part of a single loess sheet deposited over Eastern England and parts of Western Europe. Nevertheless, detailed examination of the heavy minerals content from all of these areas reveals slight areal variations especially in the proportion of hornblende. These differences show the coarse silt from North‐East Essex loess to have closest affinities with that from Norfolk. A distant source for the loess within the present North Sea Basin is proposed on textural evidence. Loess accumulation in North‐East Essex probably commenced in the few thousand years leading up to the maximumextent of Devensianice (about 18,000 years B.P.) and may have continued to about 14,

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1980.tb01039.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1980.tb01040.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

The current system of nomenclature for landform elements associated with deglaciation is often insufficient and inappropriate to describe the total depositional environment. There is a manifold transition of the deposits in regard to morphology, orientation, arrangement, material, and material‐related properties. A multidimensional scheme constructed to be maximally informative of the depositional environment is presente

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1980.tb01041.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

Palaeomagnetic and palynological studies have been made of the sediments of two Finnish lakes. Geomagnetic field changes in Finland can be traced since lake sediments record the ambient geomagnetic field at, or close to, the time they are deposited. Pollen analyses provided a useful method of dating these changes since14C dates proved to be misleading.

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1980.tb01042.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

A method is presented for correlating benthonic foraminiferal communities in Late Quaternary marine sediments on continental shelves and in coastal areas with the planktonic foraminiferal stratigraphy of the North Atlantic and Norwegian Sea deep‐sea sediment

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1980.tb01043.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1980.tb01044.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY