scholarly journals Seismic interpretation of the Cretaceous unconformities and sequences in the Middle Magdalena Valley and the western margin of the Eastern Cordillera, Colombia

2021 ◽  
Vol 353 (1) ◽  
pp. 155-172
Author(s):  
Jairo Guerrero ◽  
Luis Montes ◽  
Etienne Jaillard ◽  
Andreas Kammer
Keyword(s):  
Seismic Interpretation ◽  
Western Margin ◽  
Eastern Cordillera

scholarly journals Cenozoic uplift of the Central Andes in northern Chile and Bolivia—reconciling paleoaltimetry with the geological evolution

2016 ◽  
Vol 53 (11) ◽  
pp. 1227-1245 ◽  
Author(s):  
Simon Lamb
Keyword(s):  
Lower Crust ◽  
Central Andes ◽  
Crustal Thickening ◽  
Direct Result ◽  
Western Margin ◽  
Crustal Shortening ◽  
Eastern Cordillera ◽  
Surface Uplift ◽  
Geological Evolution ◽  
History Of

The Cenozoic geological evolution of the Central Andes, along two transects between ∼17.5°S and 21°S, is compared with paleo-topography, determined from published paleo-altimetry studies. Surface and rock uplift are quantified using simple 2-D models of crustal shortening and thickening, together with estimates of sedimentation, erosion, and magmatic addition. Prior to ∼25 Ma, during a phase of amagmatic flat-slab subduction, thick-skinned crustal shortening and thickening (nominal age of initiation ∼40 Ma) was focused in the Eastern and Western Cordilleras, separated by a broad basin up to 300 km wide and close to sea level, which today comprises the high Altiplano. Surface topography at this time in the Altiplano and the western margin of the Eastern Cordillera appears to be ∼1 km lower than anticipated from crustal thickening, which may be due to the pull-down effect of the subducted slab, coupled to the overlying lithosphere by a cold mantle wedge. Oligocene steepening of the subducted slab is indicated by the initiation of the volcanic arc at ∼27–25 Ma, and widespread mafic volcanism in the Altiplano between 25 and 20 Ma. This may have resulted in detachment of mantle lithosphere and possibly dense lower crust, triggering 1–1.5 km of rapid uplift (over ≪5 Myrs) of the Altiplano and western margin of the Eastern Cordillera and establishing the present day lithospheric structure beneath the high Andes. Since ∼25 Ma, surface uplift has been the direct result of crustal shortening and thickening, locally modified by the effects of erosion, sedimentation, and magmatic addition from the mantle. The rate of crustal shortening and thickening varies with location and time, with two episodes of rapid shortening in the Altiplano, lasting <5 Myrs, that are superimposed on a long-term history of ductile shortening in the lower crust, driven by underthrusting of the Brazilian Shield on the eastern margin.

Evolution of the Paran drainage basin and its relation to the Plio-Pleistocene history of the Arava Rift western margin, Israel

2000 ◽  
Vol 49 (4) ◽  
pp. 215-238 ◽  
Author(s):  
Hanan Ginat ◽  
Yoav Avni ◽  
Zvi Garfunkel ◽  
Hanan Ginata ◽  
Yosef Bartov
Keyword(s):  
Drainage Basin ◽  
Western Margin ◽  
History Of

Carbonate Seismic Interpretation Technology Update Based On Forward Modeling And Its Application In A Oilfield

2020 ◽  
Author(s):  
Bo Peng ◽  
Xin Chen ◽  
Xiaodong Wei ◽  
Haishan Sun ◽  
Qiang Liu ◽  
...  
Keyword(s):  
Forward Modeling ◽  
Seismic Interpretation

Regionally continuous Miocene rhyolites beneath the eastern Snake River Plain reveal localized flexure at its western margin: Idaho National Laboratory and vicinity

2020 ◽  
Vol 57 (3) ◽  
pp. 241-270
Author(s):  
Kyle L. Schusler ◽  
David M. Pearson ◽  
Michael McCurry ◽  
Roy C. Bartholomay ◽  
Mark H. Anders
Keyword(s):  
Volcanic Rocks ◽  
Snake River Plain ◽  
North American Plate ◽  
Snake River ◽  
Trace Element Geochemistry ◽  
Deep Borehole ◽  
Age Progression ◽  
Western Margin ◽  
Silicic Volcanic ◽  
River Plain

The eastern Snake River Plain (ESRP) is a northeast-trending topographic basin interpreted to be the result of the time-transgressive track of the North American plate above the Yellowstone hotspot. The track is defined by the age progression of silicic volcanic rocks exposed along the margins of the ESRP. However, the bulk of these silicic rocks are buried under 1 to 3 kilometers of younger basalts. Here, silicic volcanic rocks recovered from boreholes that penetrate below the basalts, including INEL-1, WO-2 and new deep borehole USGS-142, are correlated with one another and to surface exposures to assess various models for ESRP subsidence. These correlations are established on U/Pb zircon and 40Ar/39Ar sanidine age determinations, phenocryst assemblages, major and trace element geochemistry, δ18O isotopic data from selected phenocrysts, and initial εHf values of zircon. These data suggest a correlation of: (1) the newly documented 8.1 ± 0.2 Ma rhyolite of Butte Quarry (sample 17KS03), exposed near Arco, Idaho to the upper-most Picabo volcanic field rhyolites found in borehole INEL-1; (2) the 6.73 ± 0.02 Ma East Arco Hills rhyolite (sample 16KS02) to the Blacktail Creek Tuff, which was also encountered at the bottom of borehole WO-2; and (3) the 6.42 ± 0.07 Ma rhyolite of borehole USGS-142 to the Walcott Tuff B encountered in deep borehole WO-2. These results show that rhyolites found along the western margin of the ESRP dip ~20º south-southeast toward the basin axis, and then gradually tilt less steeply in the subsurface as the axis is approached. This subsurface pattern of tilting is consistent with a previously proposed crustal flexural model of subsidence based only on surface exposures, but is inconsistent with subsidence models that require accommodation of ESRP subsidence on either a major normal fault or strike-slip fault.

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