scholarly journals Quantitative stratigraphic analysis in a source-to-sink numerical framework

2018 ◽  
Author(s):  
Xuesong Ding ◽  
Tristan Salles ◽  
Nicolas Flament ◽  
Patrice Rey
Keyword(s):  
Sea Level ◽  
Trajectory Analysis ◽  
Rate Of Change ◽  
Sediment Supply ◽  
Passive Margin ◽  
Shelf Edge ◽  
Analysis Method ◽  
Source To Sink ◽  
Sedimentary Architecture ◽  
Thermal Subsidence

Abstract. The sedimentary architecture at continental margins reflects the interplay between the rate of change of accommodation creation (δA) and the rate of change of sediment supply (δS). As a result, stratigraphic interpretation increasingly focuses on understanding the link between deposition patterns and changes in δA/δS. Here, we use the landscape modelling framework pyBadlands to assess the respective performance of two well-established stratigraphic interpretation techniques: the trajectory analysis method and the accommodation succession method. In contrast to most Stratigraphic Forward Models (SFMs), pyBadlands provides self-consistent sediment supply to basin margins as it simulates erosion, sediment transport and deposition in a source-to-sink context. We present a landscape evolution that takes into account periodic sea level variations and passive margin thermal subsidence over 30 million years, under uniform rainfall. We implement the two aforementioned approaches to interpret the resulting depositional cycles at the continental margin. We first apply both the trajectory analysis and the accommodation succession methods to manually map key stratigraphic surfaces and define stratigraphic units from shelf-edge (or offlap break) trajectories, stratal terminations and stratal geometries. We then design a set of post-processing numerical tools to calculate shoreline and shelf-edge trajectories, the temporal evolution of changes in accommodation and sedimentation, and automatically produce stratigraphic interpretations. Comparing manual and automatic stratigraphic interpretations reveals that the results of the trajectory analysis method depend on time-dependent processes such as thermal subsidence whereas the accommodation succession method does not. In addition to reconstructing stratal stacking patterns, the tools we introduce here make it possible to quickly extract Wheeler diagrams and synthetic cores at any location within the simulated domain. Our work provides an efficient and flexible quantitative sequence stratigraphic framework to evaluate the main drivers (climate, sea level and tectonics) controlling sedimentary architectures and investigate their respective roles in sedimentary basins development.

scholarly journals Quantitative stratigraphic analysis in a source-to-sink numerical framework

2019 ◽  
Vol 12 (6) ◽  
pp. 2571-2585 ◽  
Author(s):  
Xuesong Ding ◽  
Tristan Salles ◽  
Nicolas Flament ◽  
Patrice Rey
Keyword(s):  
Sea Level ◽  
Trajectory Analysis ◽  
Temporal Evolution ◽  
Rate Of Change ◽  
Sediment Supply ◽  
Shelf Edge ◽  
Analysis Method ◽  
Stratigraphic Analysis ◽  
Source To Sink ◽  
Thermal Subsidence

Abstract. The sedimentary architecture at continental margins reflects the interplay between the rate of change of accommodation creation (δA) and the rate of change of sediment supply (δS). Stratigraphic interpretation increasingly focuses on understanding the link between deposition patterns and changes in δA∕δS, with an attempt to reconstruct the contributing factors. Here, we use the landscape modelling code pyBadlands to (1) investigate the development of stratigraphic sequences in a source-to-sink context; (2) assess the respective performance of two well-established stratigraphic interpretation techniques: the trajectory analysis method and the accommodation succession method; and (3) propose quantitative stratigraphic interpretations based on those two techniques. In contrast to most stratigraphic forward models (SFMs), pyBadlands provides self-consistent sediment supply to basin margins as it simulates erosion, sediment transport and deposition in a source-to-sink context. We present a generic case of landscape evolution that takes into account periodic sea level variations and passive margin thermal subsidence over 30 million years, under uniform rainfall. A set of post-processing tools are provided to analyse the predicted stratigraphic architecture. We first reconstruct the temporal evolution of the depositional cycles and identify key stratigraphic surfaces based on observations of stratal geometries and facies relationships, which we use for comparison to stratigraphic interpretations. We then apply both the trajectory analysis and the accommodation succession methods to manually map key stratigraphic surfaces and define sequence units on the final model output. Finally, we calculate shoreline and shelf-edge trajectories, the temporal evolution of changes in relative sea level (proxy for δA) and sedimentation rate (proxy for δS) at the shoreline, and automatically produce stratigraphic interpretations. Our results suggest that the analysis of the presented model is more robust with the accommodation succession method than with the trajectory analysis method. Stratigraphic analysis based on manually extracted shoreline and shelf-edge trajectory requires calibrations of time-dependent processes such as thermal subsidence or additional constraints from stratal terminations to obtain reliable interpretations. The 3-D stratigraphic analysis of the presented model reveals small lateral variations of sequence formations. Our work provides an efficient and flexible quantitative sequence stratigraphic framework to evaluate the main drivers (climate, sea level and tectonics) controlling sedimentary architectures and investigate their respective roles in sedimentary basin development.

The arrival of the paleo–Orinoco Delta at Trinidad: The Cruse Formation delta lobes and delivery to deepwater Atlantic

2020 ◽  
Vol 90 (8) ◽  
pp. 938-968
Author(s):  
Ariana Osman ◽  
Ronald J. Steel ◽  
Ryan Ramsook ◽  
Cornel Olariu ◽  
Si Chen
Keyword(s):  
Sea Level ◽  
Late Miocene ◽  
Sediment Supply ◽  
Average Height ◽  
Shelf Edge ◽  
Sea Level Changes ◽  
Orinoco Delta ◽  
Basin Floor ◽  
Shelf Margin ◽  
High Sediment

ABSTRACT Icehouse continental-shelf-margin accretion is typically driven by high-sediment-supply deltas and repeated glacio-eustatic, climate-driven sea-level changes on a ca. 100 ky time scale. The paleo–Orinoco margin is no exception to this, as the paleo–Orinoco River Delta with its high sediment load prograded across Venezuela, then into the Southern and Columbus basins of Trinidad since the late Miocene, depositing a continental-margin sedimentary prism that is > 12 km thick, 200 km wide, and 500 km along dip. The Cruse Formation (> 800 m thick; 3 My duration) records the first arrival of the paleo–Orinoco Delta into the Trinidad area. It then accreted eastwards, outwards onto the Atlantic margin, by shallow to deepwater clinoform increments since the late Miocene and is capped by a major, thick flooding interval (the Lower Forest Clay). Previous research has provided an understanding of the paleo–Orinoco Delta depositional system at seismic and outcrop scales, but a clinoform framework detailing proximal to distal reaches through the main fairway of the Southern Basin has never been built. We integrate data from 58 wells and outcrop observations to present a 3-D illustration of 15 mapped Cruse clinoforms, in order to understand the changing character of the first Orinoco clastic wedge on Trinidad. The clinoforms have an undecompacted average height of 550 m, estimated continental slope of 2.5° tapering to 1°, and a distance from shelf edge to near-base of slope of > 10 km. The clinoform framework shows trajectory changes from strong shelf-margin progradation (C10–C13) to aggradation (C14–C20) and to renewed progradation (C21–24). Cruse margin progradational phases illustrate oblique clinothem geometries that lack well-developed topsets but contain up to 70 m (200 ft) thick, deepwater slope channels. This suggests a high supply of sediment during periods of repeated icehouse rise and fall of eustatic sea level, with fall outpacing subsidence rates at times, and delivery of sand to the deepwater region of the embryonic Columbus channel region. Also, evidence of wholesale shelf-edge collapse and canyon features seen in outcrop strongly suggest that deepwater conduits for sediment dispersal and bypass surfaces for Cruse basin-floor fans do exist. The change to a topset aggradational pattern with a rising shelf trajectory may be linked to increased subsidence associated with eastward migration of the Caribbean plate. The Cruse-margin topsets were dominated by mixed fluvial–wave delta lobes that were effective in delivery of sands to the basin floor. The preservation of a fluvial regime of the delta may have been impacted by basin geometry which partly sheltered the area from the open Atlantic wave energy at the shelf edge. Ultimately, understanding shelf-edge migration style as well as process-regime changes during cross-shelf transits of the delta will help to predict the location of bypassed sands and their delivery to deepwater areas.

The Alberta foreland basin: relationship between stratigraphy and Cordilleran terrane-accretion events

1989 ◽  
Vol 26 (10) ◽  
pp. 1964-1975 ◽  
Author(s):  
Douglas J. Cant ◽  
Glen S. Stockmal
Keyword(s):  
Sea Level ◽  
Foreland Basin ◽  
Temporal Correlation ◽  
Sediment Supply ◽  
Passive Margin ◽  
Sea Level Fluctuations ◽  
Lithospheric Flexure ◽  
Half Wavelength ◽  
Bending Stresses ◽  
Clastic Wedges

A foreland-basin sequence resulting from accretion of a terrane to a continental passive margin ideally should be unconformity bounded, with a shallowing-upward pattern, like the classic Flysch to Molasse sequence of Alpine foreland basins. The basal unconformity is cut as the peripheral bulge associated with lithospheric flexure migrates cratonward ahead of the basin and the advancing overthrusts. The shallowing occurs because sediment supply at first is low – early stages of accretion near the continental slope generate little or no topography above sea level; later stages result in significant tectonic uplift, and much sediment is shed into the foreland, filling the basin. The upper unconformity is cut as lithospheric bending stresses are relaxed following overthrusting, and reduction of the flexural load on the lithosphere through erosion and (or) tectonic denudation of the overthrusts causes regional uplift or basin "rebound". Actual sequences show differences from this idealized version in that (i) basal unconformities may not develop under conditions of high eustatic sea level; and (ii) they may not shallow upward in all cases. These differences can occur because later terranes that accrete onto the seaward side of a previously accreted terrane may simply push it farther onboard, thus initiating sediment supply as rapidly as the load-induced subsidence. Also, in this way, a small terrane can influence the filling of a foreland basin that is more than one "lithospheric flexural half-wavelength" away from the site of accretion.The stratigraphy of the Alberta basin has been divided after comparison with the idealized sequence resulting from an individual accretion event. The six clastic wedges recognized (Fernie–Kootenay, Mannville, Dun vegan, Belly River, Edmonton, and Paskapoo) show a temporal correlation with the times of accretion of terranes (Intermontane superterrane, Bridge River, Cascadia, Insular superterrane, Pacific Rim – Chugach, and Olympic, respectively) in the Cordillera. Therefore, the stratigraphy of the foreland basin may be best interpreted in terms of Cordilleran tectonics rather than sea-level fluctuations. Eustatic sea-level variations are believed to affect the internal stratigraphy and sedimentology of some clastic wedges and are responsible for the deposition of some thin units, but they appear to operate on time scales that differ from those of the clastic wedges identified here.

scholarly journals The effects of differential compaction on clinothem geometries and shelf-edge trajectories

Geology ◽  
2019 ◽  
Vol 47 (11) ◽  
pp. 1011-1014 ◽  
Author(s):  
Daan Beelen ◽  
Christopher A.-L. Jackson ◽  
Stefano Patruno ◽  
David M. Hodgson ◽  
João P. Trabucho Alexandre
Keyword(s):  
Sea Level ◽  
Sedimentary Facies ◽  
Sediment Supply ◽  
Shelf Edge ◽  
Fine Grained ◽  
Vertical Extension ◽  
Basin Floor ◽  
Sediment Transfer ◽  
Stacking Patterns ◽  
Basin Margin

Abstract The geometry of basin-margin strata documents changes in water depth, slope steepness, and sedimentary facies distributions. Their stacking patterns are widely used to define shelf-edge trajectories, which reflect long-term variations in sediment supply and relative sea-level change. Here, we present a new method to reconstruct the geometries and trajectories of clinoform-bearing basin-margin successions. Our sequential decompaction technique explicitly accounts for downdip lithology variations, which are inherent to basin-margin stratigraphy. Our case studies show that preferential compaction of distal, fine-grained foresets and bottomsets results in a vertical extension of basin-margin strata and a basinward rotation of the original shelf-edge trajectory. We discuss the implications these effects have for sea-level reconstructions and for predicting the timing of sediment transfer to the basin floor.

scholarly journals Supplemental Material: Widespread glacial erosion on the Scandinavian passive margin

2021 ◽  
Author(s):  
Vivi Pedersen ◽  
et al.
Keyword(s):  
Sea Level ◽  
Passive Margin ◽  
Dynamic Topography ◽  
Glacial Erosion ◽  
Source To Sink ◽  
Effective Elastic Thickness ◽  
Wedge Volume

Table S1 (source to sink analysis), and the influence of dynamic topography (Fig. S1), effective elastic thickness (Fig. S2), and paleo sea level Fig. S3) on shelf wedge volume and bedrock deflection.<br>

scholarly journals Supplemental Material: Widespread glacial erosion on the Scandinavian passive margin

2021 ◽  
Author(s):  
Vivi Pedersen ◽  
et al.
Keyword(s):  
Sea Level ◽  
Passive Margin ◽  
Dynamic Topography ◽  
Glacial Erosion ◽  
Source To Sink ◽  
Effective Elastic Thickness ◽  
Wedge Volume

Table S1 (source to sink analysis), and the influence of dynamic topography (Fig. S1), effective elastic thickness (Fig. S2), and paleo sea level Fig. S3) on shelf wedge volume and bedrock deflection.<br>

scholarly journals Contributions of Organic and Mineral Matter to Vertical Accretion in Tidal Wetlands across a Chesapeake Bay Subestuary

2021 ◽  
Vol 9 (7) ◽  
pp. 751
Author(s):  
Jenny R. Allen ◽  
Jeffrey C. Cornwell ◽  
Andrew H. Baldwin
Keyword(s):  
Organic Matter ◽  
Sea Level Rise ◽  
Chesapeake Bay ◽  
Sea Level ◽  
210Pb Dating ◽  
Sediment Supply ◽  
Mineral Matter ◽  
Tidal Wetlands ◽  
Vertical Accretion ◽  
Inorganic Matter

Persistence of tidal wetlands under conditions of sea level rise depends on vertical accretion of organic and inorganic matter, which vary in their relative abundance across estuarine gradients. We examined the relative contribution of organic and inorganic matter to vertical soil accretion using lead-210 (210Pb) dating of soil cores collected in tidal wetlands spanning a tidal freshwater to brackish gradient across a Chesapeake Bay subestuary. Only 8 out of the 15 subsites had accretion rates higher than relative sea level rise for the area, with the lowest rates of accretion found in oligohaline marshes in the middle of the subestuary. The mass accumulation of organic and inorganic matter was similar and related (R2 = 0.37). However, owing to its lower density, organic matter contributed 1.5–3 times more toward vertical accretion than inorganic matter. Furthermore, water/porespace associated with organic matter accounted for 82%–94% of the total vertical accretion. These findings demonstrate the key role of organic matter in the persistence of coastal wetlands with low mineral sediment supply, particularly mid-estuary oligohaline marshes.

scholarly journals Multi-Proxy Provenance Analyses of the Kingriali and Datta Formations (Triassic—Jurassic Transition): Evidence for Westward Extension of the Neo-Tethys Passive Margin from the Salt Range (Pakistan)

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 573
Author(s):  
Shahid Iqbal ◽  
Michael Wagreich ◽  
Mehwish Bibi ◽  
Irfan U. Jan ◽  
Susanne Gier
Keyword(s):  
Lower Jurassic ◽  
Sediment Supply ◽  
Heavy Mineral ◽  
Passive Margin ◽  
Indian Plate ◽  
Late Triassic ◽  
Indian Shield ◽  
Margin Setting ◽  
Salt Range ◽  
Mineral Data

The Salt Range, in Pakistan, preserves an insightful sedimentary record of passive margin dynamics along the NW margin of the Indian Plate during the Mesozoic. This study develops provenance analyses of the Upper Triassic (Kingriali Formation) to Lower Jurassic (Datta Formation) siliciclastics from the Salt and Trans Indus ranges based on outcrop analysis, petrography, bulk sediment elemental geochemistry, and heavy-mineral data. The sandstones are texturally and compositionally mature quartz arenites and the conglomerates are quartz rich oligomictic conglomerates. Geochemical proxies support sediment derivation from acidic sources and deposition under a passive margin setting. The transparent heavy mineral suite consists of zircon, tourmaline, and rutile (ZTR) with minor staurolite in the Triassic strata that diminishes in the Jurassic strata. Together, these data indicate that the sediments were supplied by erosion of the older siliciclastics of the eastern Salt Range and adjoining areas of the Indian Plate. The proportion of recycled component exceeds the previous literature estimates for direct sediment derivation from the Indian Shield. A possible increase in detritus supply from the Salt Range itself indicates notably different conditions of sediment generation, during the Triassic–Jurassic transition. The present results suggest that, during the Triassic–Jurassic transition in the Salt Range, direct sediment supply from the Indian Shield was probably reduced and the Triassic and older siliciclastics were exhumed on an elevated passive margin and reworked by a locally established fluvio-deltaic system. The sediment transport had a north-northwestward trend parallel to the northwestern Tethyan margin of the Indian Plate and normal to its opening axis. During the Late Triassic, hot and arid hot-house palaeoclimate prevailed in the area that gave way to a hot and humid greenhouse palaeoclimate across the Triassic–Jurassic Boundary. Sedimentological similarity between the Salt Range succession and the Neo-Tethyan succession exposed to the east on the northern Indian passive Neo-Tethyan margin suggests a possible westward extension of this margin.

scholarly journals Did the last sea level lowstand always lead to cross-shelf valley formation and source-to-sink sediment flux?

2006 ◽  
Vol 111 (F4) ◽  
Author(s):  
Torbjörn E. Törnqvist ◽  
Santina R. Wortman ◽  
Zenon Richard P. Mateo ◽  
Glenn A. Milne ◽  
John B. Swenson
Keyword(s):  
Sea Level ◽  
Sediment Flux ◽  
Source To Sink
Sign in / Sign up

Export Citation Format

Share Document