The geometry of the Joint Pattern and its relation with fold structures in the Aywaille Area (Ardennes, Belgium)
The orientation of intersecting joint-planes were recorded together with the bedding-plane, resulting in 4 sets which are related orthogonally to the bedding-plane and geometrically to the regional fold structure. The model of Price (1966
), describing the generation of joints in relation with folding, cannot explain completely the formation of the joint-sets. (LW).
This paper discusses not only the geometrical features, but also the strain pattern of folds developed in quartzitic layers in a Variscan transpressive domain. Strain data from the deformed northern Portugal Ordovician quartzites show that folding
Stream response to repeated coseismic folding, Tiptonville dome, New Madrid seismic zone
Channel geometry ; Earthquake ; Folding ; Geochronology ; Meander ; Mississippi ; Stream ; United States of America
Active folding in the New Madrid seismic zone (NMSZ) forms the Tiptonville dome, a 15 km long and 5 km wide surface fold with up to 11 m of late Holocene structural relief. The fold is crossed by streams of varying size, from the Mississippi River
folding produced by these earthquakes; and to partition the amount of deformation produced by individual events.
River response to an active fold-and-thrust belt in a convergent margin setting, North Island, New Zealand
Digital elevation model ; Fluvial processes ; Fluvial terrace ; Folding ; Geomorphology ; New Zealand ; North Island ; Quaternary ; Tectonic thrust
High-resolution digital elevation data (TOPSAR 10-m grid) are used to reconstruct Late Quaternary growth histories of subtle folding in the Wairapa fold-and-thrust belt, North Island, New Zealand. Outcrop data of deformed latest Miocene and younger
strata are combined with observations of warped and faulted late Quaternary terrace surfaces to unravel the geomorphic and structural history of the Huangarua River valley. These data permit comparison of short-term and long-term patterns of folding
and enable to assess the impact of differential fold growth and climatically induced processes, such as variable sediment flux, on terrace genesis.
The advancement of the lower parts of the glacier-foot into and across the sands of the foreland implies the following genesis of push-moraines: Shoving off a place of sand, folding it and pushing it over the foreland at average rates of up to 7,2
mm/h, according to the investigations in the summer of 1983. At a certain stage of the folding process, new folds begin to develop in front of the old, and the old folds are shifted onto the backslope of the folds in front of them until
they are completely united. In this way, pile-moraines arise, which become higher and higher. They include two or more folds declining towards the glacier. Systems of small moraines presumably of the same genesis occur on old moraine areas in front of the Kotlujokull
The forms of rock slopes in the Cape Fold Mountains
The forms of rock slopes developed on the quartzitic sandstones of the folded Cape Supergroup strata are explained with reference to rock mass strength and the characteristics of rock masses. (AJC).
Development of basement-involved fold and thrust structures exemplified by the Tatric-Fatric-Veporic nappe system of the Western Carpathians (Slovakia)
This paper describes the map-scale geometry of basement-involved fold and thrust structures occurring within an intracontinental convergence zone in the Central Western Carpathians (CWC) of Slovakia. A system of ductile basement/cover large-scale
folds formed here by rotation of pre-existing, closely spaced, domino-type normal faults. However, the advancement of the wedge was likely accomplished by formation of a new thrust fault rooted in the ductile lower and/or middle crust.
Geometry and timing of deformation inside a structural arc : the case of the western Emilian folds (Northen Apennine front, Italy)
of the belt. In this paper the AA. analyse subsurface data in order to give a quantitative description of a lateral ramp affecting the Northern Apennine front inside the arcuate Emilian folds. - (NF)
Recent fold growth and drainage development : the Janauri and Chandigarh anticlines in the Siwalik foothills, northwest India
the geomorphic and hydrographic expressions of the Chandigarh and the Janauri active anticlines in the NW India Siwaliks. To investigate the morphological scenario during the folding process, they used spatial imagery, geomorphometric parameters extracted from
Tilting of active folds and drainage asymmetry on the Manawatu Anticlines, New Zealand : a preliminary investigation
Asymmetry ; Drainage ; Folding ; New Zealand ; North Island ; Tectonics ; Watershed
are used to determine whether westward-flowing trunk streams on the gentle western limbs of 5 anticlines are migrating southwards across their drainage basins, concomitant with down-tilting of the fold axes. While results show potential for the techniques
Glacially folded outwash near Lago Llanquihue, southern Lake District, Chile
Folded outwash occurs in 4 distinct clusters in an arcuate arrangement just west of the terminal Llanquihue moraines deposited by the Lago Llanquihue piedmont ice lobe at the last glacial maximum. The AA. report here on the analyses of an unusual
feature in this context and present possible interpretations of the results. They conclude that the folded outwash represents a variety of push moraines.
Morphotectonic evidence from lateral propagation of an active frontal fold; Pakuashan anticline, foothills of Taiwan
This paper demonstrates that a combined study, based on geomorphological, stratigraphical and tectonic analysis, allows precise understanding of the structure and evolution of an active fold. The aims of the study are to document : 1) the structures
that accommodate lateral propagation on an active fold; 2) the orientation of the principal stress-axis inferred from fault population analysis in the pretectonic Toukoshan Formation and syntectonic deposits; and 3) the tectonic geomorphology of the Pakuashan
Soil-landform development of a part of the fold belt along the eastern coast of Bangladesh
This study attempts investigations of geomorphology and soils of a part of coastal area of Bangladesh, and to work out the role of different pedogenic processes, neotectonic activities (folding), and Late Quaternary climate/sea-level fluctuations
combined effects of eustatic sea level and tectonic uplift due to folding.