Mapping Of Sediments Research Articles

Fossil diatoms and Biostratigraphy of the lower Karewa formation of Kashmir

During the course of geological mapping of the Karewa sediments of Kashmir to assess the economic potentialities of diatomaceous earth, the author collected nearly one thousand samples from 32 measured sections. The samples were analysed for fossil diatoms.
 The study has indicated that while the lower Karewa is very rich in fossil diatoms, the upper Karewa is devoid of them. It is further observed that there is a uniformity in the trend of distribution and assemblages of fossil diatoms in the lower Karewa beds. Based on these two factors, the lower Karewa is divided into two biozones, the lower - Centrales Assemblage Zone, characterized by the predominance of centric diatoms and the upper – Pennales Assemblage Zone, characterized by the predominance of pennate diatoms.

Field mapping and geophysical work in the Scoresby Sund region, East Greenland

The fourth season of the five-year mapping programme in the Scoresby Sund region was carried out in July and August. A tent base camp was established at the head of Hurry Inlet and served as operation centre for 3 helicopters. The Norwegian sealer "Brandal", and a small cutter provided transport in the fjords. The expedition members numbered 44, comprising 16 geological two-man parties and supporting personnel. Five parties mapped in the crystalline complex of Liverpool Land and one party the Caledonian supracrustal and igneous rocks on Canning Land. Mapping of the post-Caledanian sediments in Jameson Land and southern Scoresby Land was undertaken by six parties (see Birkelund and Perch-Nielsen, this repart). Two parties mapped the eastern part of the Tertiary basalt area south af Scoresby Sund and one undertook Quaternary investigations in the central and eastern part of the Scoresby Sund region. A geophysical party carried out a terrestrial magnetometer investigation across central Jameson Land and a shipborne investigation in Scoresby Sund and Hall Bredning.

Field mapping of Palaeozoic, Mesozoic and Tertiary sediments in the Scoresby Sund region, East Greenland

An eight-week. field season concluded the four-year mapping project on the Phanerozoic sediments of the Scoresby Sund region. Six teams worked in Scoresby Land, Jameson Land, Liverpool Land and the Kap Brewster area (see Henriksen, this report). In addition to the authors the following took part in the 1971 mapping: R. G. Bromley, U. Asgard, F. Surlyk (Univ. of Copenhagen), M. Aellen (Eidg. Techn. Hochschule, Zurich), J. H. Callomon (Univ. of London) and K. Birkenmajer (Polish Acad. ScL, Krakow).

13.—Sea-floor Sediment Mapping by Sonar Methods

SynopsisA system is described which produces true-to-scale sonar maps of the sediment patterns on the seabed of the Continental Shelf waters. Correction is made for the speed of the ship over ground, and the 'drift angle' of the sonar beam during passage from one station to another. Work at sea has been extended to water depths of 250 metres, and the technique has been widely used for cable route surveys.