Structure and kinematics of an outcrop-scale fold-cored triangle zone

authored by: David Colin Tanner, Christian Brandes, Bernd Leiss
Abstract: Triangle zones are widespread structural elements that link fold and thrust belts with their foreland basins. We present a structural analysis of an outcrop-scale (∼6 m [20 ft] wide) triangle zone that is exposed in the siliciclastic Carboniferous strata of the Harz Mountains in northern Germany. The geometry of the triangle zone is critically compared with larger outcrop and seismic-scale structures. The external form of the triangle zone is the same as that proposed for larger examples, with two bounding detachments that dip in opposing directions. However, the interior of the triangle zone is characterized by tight to isoclinal folds. We demonstrate how the triangle zone probably evolved from a fault-bend fold, which accreted further folds behind it. This is an alternative fold-based interpretation for a structure that is commonly modeled as a duplex stack. We present the resulting consequences for seismic interpretation and hydrocarbon reservoir evaluation.
Organisation(s): Institute of Geology
External Organisation(s): Leibniz Institute for Applied Geophysics (LIAG)
University of Göttingen
Type: Article
Journal: AAPG bulletin
Volume: 94
Pages: 1799-1809
No. of pages: 11
ISSN: 0149-1423
Publication date: 12.2010
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Fuel Technology, Energy Engineering and Power Technology, Geology, Geochemistry and Petrology, Earth and Planetary Sciences (miscellaneous)
Electronic version(s): https://doi.org/10.1306/06301009188 (Access: Unknown)

BibTeX

@article{2ec94c7c181c4dbba756f1cf41f3f251,
title = "Structure and kinematics of an outcrop-scale fold-cored triangle zone",
abstract = "Triangle zones are widespread structural elements that link fold and thrust belts with their foreland basins. We present a structural analysis of an outcrop-scale (∼6 m [20 ft] wide) triangle zone that is exposed in the siliciclastic Carboniferous strata of the Harz Mountains in northern Germany. The geometry of the triangle zone is critically compared with larger outcrop and seismic-scale structures. The external form of the triangle zone is the same as that proposed for larger examples, with two bounding detachments that dip in opposing directions. However, the interior of the triangle zone is characterized by tight to isoclinal folds. We demonstrate how the triangle zone probably evolved from a fault-bend fold, which accreted further folds behind it. This is an alternative fold-based interpretation for a structure that is commonly modeled as a duplex stack. We present the resulting consequences for seismic interpretation and hydrocarbon reservoir evaluation.",
author = "Tanner, {David Colin} and Christian Brandes and Bernd Leiss",
year = "2010",
month = dec,
doi = "10.1306/06301009188",
language = "English",
volume = "94",
pages = "1799--1809",
journal = "AAPG bulletin",
issn = "0149-1423",
publisher = "American Association of Petroleum Geologists",
number = "12",
}