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The deep-water region offshore NW Borneo is an active fold-and-thrust belt that hosts a signifi cant number of proven hydrocarbon accumulations. In the past, two mechanisms have been discussed as primary control for Neogene to Holocene folding and thrusting in this deep-water province: (1) basement-driven crustal shortening and (2) gravity-related delta tectonics. In this study, new, balanced interpretations of regional, crustal-scale, depth-migrated, twodimensional (2-D), multichannel seismicrefl ection profi les are presented that provide for the fi rst time quantitative data on tectonic shortening throughout the entire deep-water fold-and-thrust belt of NW Borneo. We use our tectonic restorations to compare the amount of deep-water shortening on the NW Borneo slope to the amount of extension across the NW Borneo shelf. A key result of this balancing study is the observation that Pliocene to Holocene gravity-driven shortening decreases from south to north, while the total amount of shortening increases slightly to the north. Consequently, the amount of purely basement-driven compression along NW Borneo is strongly inferred to increase toward the north. Because most of the shortening is late Pliocene and younger, we interpret the tectonic shortening to be ongoing.

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The southern Makran fold-thrust belt, Pakistan, displays unique outcrop examples of wellexposed, kilometre-scale, listric growth faults that displace Miocene-age deltaic growth strata by several hundreds of metres to kilometers. The largest growth faults are counter-regional (landward-dipping), bounding major clastic depocentres exposed over areas > 1000 km 2 .Stratal offset along these faults can exceed 1.5 km. Fault-zone thicknesses range between ca. 100 and 400 m, and average fault thickness-displacement ratios are around 1:10. Highresolution satellite data show in unprecedented detail the faults and the stratigraphic architecture of associated growth sequences, which comprise kilometre-scale progradational clinoforms, thick mudstone units and basinwards wedging sandstone-shale deposits. The true vertical thickness of the syn-kinematic record is, in places, up to 8 km, making the outcrop examples equivalent to major growth faulted successions known from seismic data of large deltas, and at least an order of magnitude larger than other outcrop examples. A comparison of the Makran outcrops with seismic-reflection examples offshore NW Borneo reveals distinct similarities in the gross depocentre geometries and internal architecture. The key control for growth faulting is interpreted to result from sedimentary loading, with rapid sedimentary progradation causing the development of rollover synclines by differential compaction and fluid expulsion, and counter-regional growth faults preferentially forming on the basinward side of these synclines. The data and interpretations presented can be used to assess the key parameters that contribute to the development of growth faults and growth successions above shale, reinforcing structural and stratigraphic observations from seismic interpretation and modelling studies in demonstrating their occurrence in exposure.

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Classically, the North-Sea Chalk is assumed to have deposited under quiet, homogeneous pelagic conditions with local re-deposition in slumps and slides. However, recently the observation of highly discontinuous reflection patterns on 2D and 3D seismic data from the NW European Chalk Group initiated a revision of some general ideas of chalk deposition, assuming that long-lived, contour-parallel bottom currents exert a primary influence on the development of intra-chalk channels, drifts and mounds. In this study, an alternative explanation is suggested for the formation of many of the significant intra-chalk seismic and stratal discontinuities by interpreting these as being caused by gravity-driven processes developing in response to intense syndepositional tectonics. Submarine mass-transport systems identified in the study area include large-scale slumps, slides, debris flows and turbidites. The latter occur in sinuous channel systems flanked by large master overbanks, with the channel fill exhibiting well-developed secondary banks and overbanks on the respective outer bends of the inner channel thalweg. This first documentation of channelised density-flow deposits in the North-Sea Chalk has important consequences for the interpretation and prediction of re-deposited chalk units, emphasising at the same time the strength of vigorous 3D seismic discontinuity detection for subsurface sedimentary-systems analysis.