Structure of the Havallah sequence, Golconda allochthon, Nevada: Evidence for prolonged evolution in an accretionary prism: Discussion and reply

Tomlinson, Andy J.; Miller, Elizabeth L.; Holdsworth, B. K.; Whiteford, W. B.

doi:10.1130/0016-7606(1987)98<615:sothsg>2.0.co;2

Cited by 3 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This presumed missing stratigraphic record for the P-T transition means that little can be learned about the P-T event in most places and particularly within the passive margin of the western North American craton (Paull & Paull, 1994 a ). Sedimentological arguments supporting the completeness of the P-T transition have been presented (Paull, 1980; Alvarez & O'Connor, 2002), but were overwhelmed by the commonly accepted model of a significant and ubiquitous gap between Permian and Triassic (Silberling & Roberts, 1962; Tomlinson et al 1987; Miller, 1989; Wardlaw et al 1995; Ketner, 2008). This major unconformity correlated with both a global sea-level lowstand and the Sonoma orogeny, with strata of the late Guadalupian, entire Lopingian and the lower part of the Early Triassic missing (Collinson, Kendall & Marcantel, 1976; Wardlaw et al 1995).…”

Section: Introductionmentioning

confidence: 99%

New U–Pb constraints identify the end-Guadalupian and possibly end-Lopingian extinction events conceivably preserved in the passive margin of North America: implication for regional tectonics

et al. 2016

View full text Add to dashboard Cite

The discovery and dating of a volcanic ash bed within the upper Phosphoria Formation in SE Idaho, USA, is reported. The ash occurs 11 m below the top of the phosphatic Meade Peak Member and yielded a 206Pb/238U date of 260.57 ± 0.07 / 0.14 / 0.31 Ma, i.e. latest Capitanian, Guadalupian. The stratigraphic position of this ash near the top of the Meade Peak phosphatic Member of Phosphoria Formation indicates plausible completeness of the sedimentation within the Guadalupian–Lopingian and probably at the Permo-Triassic (P-T) transitions. The new radiometric age reveals that the regional biostratigraphy and palaeontology of Phosphoria and Park City formations requires serious reconsideration, particularly in cool water conodonts, bryozoans and brachiopods. The new age proposes that the Guadalupian–Lopingian boundary (GLB) coincides with the Meade Peak – Rex contact and consequently with the end-Guadalupian extinction event. The lack of a major unconformity at the P-T transition suggests that the effects of the Sonoma orogeny were not as extensive as has been assumed.

show abstract

Section: Introductionmentioning

confidence: 99%

New U–Pb constraints identify the end-Guadalupian and possibly end-Lopingian extinction events conceivably preserved in the passive margin of North America: implication for regional tectonics

et al. 2016

View full text Add to dashboard Cite

show abstract

Permo‐Triassic tectonism in volcanic arc sequences of the western U.S. Cordillera and implications for the Sonoma orogeny

Wyld¹

1991

Tectonics

View full text Add to dashboard Cite

The Permo-Triassic Sonoma orogeny, western U.S. Cordillera, involved fight folding and imbricate thrust faulting of basinal strata of the Golconda allochthon. This event is generally interpreted in terms of accretion of upper Paleozoic volcanic arc rocks of the western U.S. Cordillera ("McCloud arc") to the North American continent, either via back arc basin closure or arc-continent collision. The structural history of the McCloud arc during the Sonoma orogeny is poorly understood, however, as are the implications of this history for tectonic models. This paper presents a synthesis of the Permian to Triassic stratigraphic and structural evolution of the McCloud arc, incorporating new data from the Pine Forest Range, northwest Nevada. The synthesis indicates that, on a regional scale, the arc was affected by widespread uplift but only local tilting, folding and faulting in the Late Permian to Early Triassic. The timing of Permo-Triassic tectonic activity in the McCloud arc is thus similar to the middle Permian to Early Triassic age of deformation in the Golconda allochthon but the structures produced in the two groups of rocks differ markedly. The significance of this contrasting structural response to Sonoma age tectonism can be evaluated by comparison with other better understood examples of arc-continent accretion (back arc basin closure in the southern Andes, "compressional" arc-continent collision in New Guinea and "extensional" arccontinent collision in the Mediterranean). This comparison indicates that the contrasting structural history of the McCloud arc and Golconda allochthon is entirely compatible with an arccontinent accretion model for the Sonoma orogeny and cannot be used as a basis for concluding that the McCloud arc was not involved in the orogenic event. The comparison further indicates that either back arc basin closure or "compressional" arc-continent collision are the most likely settings for the Sonoma orogeny. In contrast, an "extensional" Mediterraneanstyle arc-continent collision, as has been recently proposed for the earlier (middle Paleozoic) Antler orogeny, is probably not an appropriate analogue for the Sonoma orogeny. The weak structural response of the McCloud arc during Sonoman compression also provides new constraints on the specific processes involved in arc accretion, either via arc-continent collision or back arc basin closure. These constraints suggest that there may be few fundamental differences between the two models during the final stages of arc accretion. Regardless of tectonic setting, Permo-Triassic uplift and associated deformation in the McCloud arc should be considered as much a response to the Sonoma orogeny as is fight folding and imbricate faulting in the Golconda allochthon. A second model interprets the arc to have been east facing, and suggests that the Havallah sequence and related rocks were deformed as they were offscraped from the subducting edge of the North American plate and incorporated into a growing accretionary prism east of the arc [Speed, 1979; Snyd...

show abstract

Speculative reconstruction of the Mojave‐Snow Lake Fault: IMPLICATIONS FOR Paleozoic and Mesozoic orogenesis in the western United States

Schweickert¹,

Lahren²

1990

Tectonics

View full text Add to dashboard Cite

Available evidence suggests that the Mojave‐Snow Lake fault, a major Early Cretaceous dextral fault with up to 400 km displacement, formerly existed in what is now the axial part of the Sierra Nevada batholith. Regional relations suggest that the fault formerly continued in western Nevada, the Mojave Desert, and in rocks now exposed in the Salinian block. Restoration of 400 km of Early Cretaceous dextral displacement on the Mojave‐Snow Lake fault leads to speculative but testable reconstructions of Mesozoic and Paleozoic tectonic features of California and Nevada. Insights derived from these reconstructions include the following: (1) Two regionally extensive Jurassic thrust belts of opposed vergence appear to have intersected in the northern Sierra Nevada. The eastern, east‐vergent thrust belt, which includes the Fencemaker and Liming thrusts in western Nevada and several east‐vergent thrusts in the northern Sierra, may be a contractional belt along which an Early Jurassic interarc or marginal basin was closed in Middle to Late Jurassic time. The western, west‐vergent thrust belt is part of the classic Nevadan orogen of the western Klamath Mountains and the western Sierra metamorphic belt, in which collisions and/or thrusting of various island arc terranes occurred during Middle and Late Jurassic time. (2) The early Mesozoic continental arc included paired belts of Triassic‐Jurassic blueschist and melange, and igneous rocks including Late Triassic and younger plutons and volcanic rocks. This conclusion is not new, but the reconstruction provides a slightly different geometry than previously thought. (3) Sonomia, the late Paleozoic island‐arc terrane of the western U. S., may have formed a relatively narrow belt extending from northwestern Nevada to the latitude of the western Mojave Desert. The geologic development of the Paleozoic basement complex of Sonomia was very different from that of the Cordilleran miogeocline in Death Valley and the Mojave Desert, requiring that a continuation of the Sonoma suture belt (or Golconda thrust) must have extended southward through the Sierra Nevada batholith to the Mojave region. (4) A heterogeneous belt of Permian to Triassic or Triassic deformation in the Mojave and eastern Sierra Nevada, together with the Golconda allochthon in Nevada, may represent the protracted response to the collision of Sonomia with the western margin of North America. The contractional deformation continued during the evolution of the early Mesozoic continental arc. (5) Several predictions can be made about the nature of concealed basement within the Sierra Nevada batholith and within western Nevada. The reconstruction suggests that elements of the Antler and Sonoma orogenic belts should underlie areas of the batholith and western Nevada, as a result of northward displacement along the Mojave‐Snow Lake fault from the western Mojave and southern Sierra Nevada.

show abstract

Structure of the Havallah sequence, Golconda allochthon, Nevada: Evidence for prolonged evolution in an accretionary prism: Discussion and reply

Cited by 3 publications

References 0 publications

New U–Pb constraints identify the end-Guadalupian and possibly end-Lopingian extinction events conceivably preserved in the passive margin of North America: implication for regional tectonics

New U–Pb constraints identify the end-Guadalupian and possibly end-Lopingian extinction events conceivably preserved in the passive margin of North America: implication for regional tectonics

Permo‐Triassic tectonism in volcanic arc sequences of the western U.S. Cordillera and implications for the Sonoma orogeny

Speculative reconstruction of the Mojave‐Snow Lake Fault: IMPLICATIONS FOR Paleozoic and Mesozoic orogenesis in the western United States

Contact Info

Product

Resources

About