Geology Reports⌕ Search
Home/Archive/USGS

USGS · 70243819

Paleozoic plate-tectonic evolution of the Tarim and western Tianshan Regions, western China

Yangshen Shi·Huafu Lu·Dong Jia·Dongsheng Cai·Shimin Wu·Chuming Chen·David G. Howell·Zenon C. Valin
View original source ↗Export metadata ↓

Abstract

The plate-tectonic evolution of the Tarim basin and nearby western Tianshan region during Paleozoic time is reconstructed in an effort to further constrain the tectonic evolution of Central Asia, providing insights into the formation and distribution of oil and gas resources. The Tarim plate developed from continental rifting that progressed during early Paleozoic time into a passive continental margin. The Yili terrane (central Tianshan) broke away from the present eastern part of Tarim and became a microcontinent located somewhere between the Junggar ocean and the southern Tianshan ocean. The southern Tianshan ocean, between the Tarim craton and the Yili terrane, was subducting beneath the Yili terrane from Silurian to Devonian time. During the Late Devonian-Early Carboniferous, the Tarim plate collided with the Yili terrane by sinistral accretional docking that resulted in a late Paleozoic deformational episode. Intracontinental shortening (A-type subduction) continued through the Permian with the creation of a magmatic belt.

Explore related subjects

International Geology ReviewArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 36.61922749358027° to 42.48569294241568° latitude; 72.1312740853939° to 104.25483193359253° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Yangshen Shi, Huafu Lu, Dong Jia, Dongsheng Cai, Shimin Wu, Chuming Chen, David G. Howell, Zenon C. Valin. 2010-07-06. Paleozoic plate-tectonic evolution of the Tarim and western Tianshan Regions, western China. https://doi.org/10.1080/00206819409465504

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related USGS reports

USGS2025

Did the Aleutian Basin form by plate capture or backarc basin opening?

The origin of the Aleutian Basin is unresolved because its crust is deeply buried beneath sediments. It has been interpreted as forming in the Eocene when the Beringian convergent margin jumped seaward to south of the Aleutian arc, thereby capturing a large sector of Cretaceous Pacific crust. Alternatively, it may have formed by backarc spreading. We present new magnetic and seismic reflection data compilations and review other pertinent data to evaluate these two possibilities. Arguments for entrapment are: 1) Palaeomagnetic and geologic data document that the Aleutian arc formed approximately in place and as a seaward, on-strike continuation of the Alaska Peninsula; 2) basin-central spreading anomalies trend N-S, normal to the Aleutian arc and exhibit amplitudes and lengths typically formed at mid-ocean ridges; 3) seismic reflection profiles document that cross-basin depositional sequences are like those expected of filling a fixed-width basin. Arguments for a backarc spreading origin include: 1) The perpendicular orientation of magnetic anomalies in the Aleutian Basin and the northern Pacific Plate suggest different origins; 2) the sub-parallel orientation of Aleutian Basin spreading magnetic fabric and Palaeogene rift basins on the Bering Shelf suggest a common extensional regime; 3) thinner continental crust beneath outer-shelf basins is consistent with extension; 4) lineated magnetic fabrics on the margins of the basin are similar to early rifting magnetic fabrics found in other backarc basins; 5) basin heat flow is consistent with Palaeogene seafloor spreading; 6) its marginal basin setting is analogous to marginal basins elsewhere that formed by extension and seafloor spreading, not entrapment; and 7) entrapment requires formation of the Aleutian subduction zone by transference, a mode of subduction initiation that has not yet been documented. We present evidence for both interpretations and underscore the need for continued data collection (e.g. scientific drilling) to test competing hypotheses. Similar approaches may be useful for understanding thickly sedimented marginal basins elsewhere.

Alaska↗
USGS2023

U-Pb zircon ages and Lu-Hf isotope systematics across northwestern Mexico: Implications for Cretaceous to Paleocene tectonomagmatic evolution during Farallon subduction

This study presents U-Pb zircon ages and Lu-Hf zircon isotope data for Cretaceous-Paleocene plutonic rocks along a W-E transect in northwestern Mexico. These data are combined with tectonic reconstruction that restores Late Cenozoic extensional deformation and shows the position of magmatism at 36 Ma. Zircon U-Pb ages results span from 142 to 58 Ma and demonstrate that the continental arc migrated northeastward at 1–2.5 km/Myr. These rates are slower than previously interpreted, but consistent with landward arc migration rates observed in the Andes. Weighted mean initial epsilon hafnium εHf( t ) values of plutonic rocks along the transect range from + 8.8 to −9.1. The heterogeneity in the zircon εHf( t ) is spatially related to the pre-Cretaceous basement provinces that the intrusive rocks were emplaced into. Zircon εHf( t ) values of western Baja California display positive values ranging from + 8.8 to + 2.6 suggesting they were formed from a moderately depleted mantle and were emplaced into the Guerrero-Alisitos-Vizcaino terrane. Zircon εHf( t ) values in the eastern part of Baja California and most of Sonora are heterogeneous ranging between −0.7 and −9.1 and may be formed from a relatively slightly more evolved mantle source and end up more evolved after crustal assimilation of metasediments. Zircon εHf( t ) values ranging from + 8.7 to + 2.9 in Chihuahua are consistent with a depleted-mantle derived melt and assimilation of Grenville lithospheric province. Our results highlight how Hf isotopic signatures help to constrain the pre-Cretaceous basement configuration in northwestern Mexico despite the few exposed outcrops along the transect.

northwestern Mexico↗
USGS2021

Comment on ‘New insights on Franciscan Complex geology, architecture, depositional age, and provenance for the western Mt. Tamalpais area, Marin County, California’ by Bero et al. (2020)

Serious errors and inconsistencies in the article undermine many of its interpretations to the point that principal conclusions are not valid. Much dependence is placed on the maximum depositional age (Dmax) of sandstone units based on zircon analysis of 10 samples, but calculation of those Dmax values is flawed, and their use confuses maximum with actual depositional ages and makes age distinctions finer than the resolution of the data. Conclusions that are compromised include the concept of a westward/downward-younging tectonostratigraphic stack of accretionary units, comparison of mapped sandstones with other California Coast Ranges sandstones, comparison of timing of events recorded in the map area with regional events, identification of mélange only in a narrow band in the study area, and detrital provenance of some of the sandstone units.

California↗