Biostratigraphy v. geophysics; correlation of Middle Turonian chalks in the Anglo-Paris Basin

Author:

Gale Andy12ORCID

Affiliation:

1. School of the Environment, Geography and Geological Sciences, University of Portsmouth, Burnaby Building, Burnaby Road, Portsmouth PO1 3QL, UK

2. Earth Science Department, Natural History Museum, Cromwell Road, London SW7 5BD, UK

Abstract

High-resolution correlations between boreholes are commonly based on a combination of geophysical well-log data and biostratigraphy, and when these conflict resolution can be contentious and difficult. Such a situation exists in the Middle Turonian chalks of the Anglo-Paris Basin, where electrical resistivity logs, registering thin but seemingly laterally continuous beds of clay-rich chalk (marls) in mostly uncored boreholes, provide apparently straightforward correlations across broad regions. In contrast, detailed biostratigraphical analysis using microcrinoids provides very different results, showing the presence of a major hiatus associated with a hardground and differing significantly from the geophysical correlations. Detailed re-examination of this contentious problem, utilizing exposures adjacent to boreholes, demonstrates the supremacy of detailed biostratigraphical analysis, independently supported by regional thickness patterns, cyclostratigraphy and geochemistry. Although closely spaced geophysical well logs can afford convincing correlations, their use in correlation over broader geographical regions leads to erroneous and misleading conclusions.

Publisher

Geological Society of London

Subject

Geology

Reference31 articles.

1. Bailey, H.W. and Wood, C.J. 2010. The Upper Cretaceous Chalk. In: Catt, J. (ed.) Hertfordshire Geology and Landscape. Hertfordshire Natural History Society, 36–60.

2. The lithostratigraphy of the English Chalk Rock

3. Brydone, R.M. 1911. The Stratigraphy of the Chalk of Hants. Dulau.

4. Turonian correlation and sequence stratigraphy of the Chalk in southern England

5. An integrated microcrinoid zonation for the lower Campanian chalks of southern England, and its implications for correlation

Cited by 1 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

1. Intra-Turonian stratigraphic reorganization on the Arabian Plate;Geological Society, London, Special Publications;2024-07-15

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3