摘要:

Relict shallow water sediments, formed during the post-glacial rise in sea. revel, cover the continental shelf off northernmost New Zealand. Supplies of detrital sediment are negligible and biogenic skeletal debris is the only sediment component being supplied to the sea floor at present in any large quantity. Glauconite is forming over much of the region and active sediment movement is restricted to the nearshore environment.

ISSN:0028-8306    

DOI:10.1080/00288306.1969.10420233

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

Two new trace-fossil occurrences are described from the New Zealand Tertiary succession. They consist of a large variety ofZoophycosfrom the Oligocene near Murchison, and the association of a large and small variety ofChondritesfrom the Lower - Middle Paleocene of the Wairarapa. Also, fucoidal markings in the Upper Paleocene - Lower Eocene of the Wairarapa are identified as sections across theZoophycossepta. TheZoophycosstructures are interpreted as the product of systematic mining activity by a worm-like animal in the sediment. SimilarChondritesassociations occur in flysch sediments of Austria.

ISSN:0028-8306    

DOI:10.1080/00288306.1969.10420234

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

This paper presents a further detailed stratigraphic column showing the alternating sequence of sandstones and siltstones of the Lower Miocene Waitemata turbidite sediments. Descriptions of the sedimentary features, current direction indicators, grain size analyses, petrology, and trace fossils are given especially with regard to their use as possible correlation factors. The use of a model relating current direction variation within an expanding lobate turbidity current is discussed, together with its application for determining axial flow direction of the turbidity current and the direction of thickening of the turbidite sandstone. It is concluded that the best possible method of correlating the uniform sequence of unfossiliferous sediments available at present is by means of close spaced detailed stratigraphic columns together with graphs of sandstone-siltstone ratio and bed thickness variations with respect to stratigraphic height.

ISSN:0028-8306    

DOI:10.1080/00288306.1969.10420235

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

Rocks belonging to a turbidite facies of the Lower Miocene Waitemata Group are exposed extensively about Whangaparaoa Peninsula. Interbedded with this sequence are a number of thick, distinctive, volcaniclastic grits believed to have been emplaced by submarine lahars. These sediments accumulated towards the axial parts of a marine basin within a continental borderland. The turbidites were deposited by predominantly south-east - flowing currents. Directions of weak bottom (traction) currents were more variable. Deformation and contortion of strata occur on a grand scale and are attributed to the penecontemporaneous slumping of poorly consolidated sediments in response to tilting of the sea floor. Injection of clastic dikes accompanied later stages of movement in slumped sequences. Evidence suggests that one great slump sheet extends over a distance of at least 10 miles from near Red Beach in the west to Whangaparaoa Head and possibly Tiritiri Matangi in the east.

ISSN:0028-8306    

DOI:10.1080/00288306.1969.10420236

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

A sedimentological study of the Tertiary sediments of the Mandamus - Dove River area in North Canterbury, New Zealand, indicates that fluvial conglomerates and coal were the first sediments deposited on a Cretaceous peneplain developed on greywackes of the Torlesse Group. Subsequent cross-bedded glauconitic sands were deposited by north-flowing longshore currents following marine transgression in the area. Rapid build-up of bedded tuffs produced by volcanic activity to the north-east diverted longshore current sedimentation from the area and permitted an environment suitable for the growth of an algal—crinoidal—bryozoan biostrome. Cessation of volcanic activity and continuing basin subsidence halted biostrome growth and allowed renewed deposition of detritus by marine currents.

ISSN:0028-8306    

DOI:10.1080/00288306.1969.10420237

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

摘要:

The western Tasman Sea floor is characterised by physiographic units that tend to parallel the coastline of south-eastern Australia. The margin has a narrow continental shelf and a steep continental slope. Sediment derived mainly from northern New South Wales and Queensland in the north, and from Tasmania and Victoria in the south, has built a system of fans forming the lower continental slope, continental rise, and Tasman Abyssal Plain.

ISSN:0028-8306    

DOI:10.1080/00288306.1969.10420238

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

ISSN:0028-8306    

DOI:10.1080/00288306.1969.10420239

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

ISSN:0028-8306    

DOI:10.1080/00288306.1969.10420240

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor

ISSN:0028-8306    

DOI:10.1080/00288306.1969.10420241

出版商:Taylor & Francis Group    

年代:1969

数据来源: Taylor