C. R. van Staal

• PhD
• Emeritus at Natural Resources Canada

The 290-282 Ma ophiolitic Liuyuan Complex in northwestern China preserves a section of oceanic crust formed in a back-arc basin during the final stages of the evolution of the Central Asian Orogenic Belt. We present results of detailed field work, petrography, whole rock, and mineral chemistry of the plutonic rocks of the Liuyuan Complex. These inc...

The 290-282 Ma ophiolitic Liuyuan Complex in northwestern China preserves a section of oceanic crust formed in a back-arc basin during the final stages of the evolution of the Central Asian Orogenic Belt. We present results of detailed field work, petrography, whole rock, and mineral chemistry of the plutonic rocks of the Liuyuan Complex. These inc...

Our multidisciplinary study of the southern Beishan orogen in NW China, situated between the Tienshan and Solonker suture zones, sheds light on the closure of the Paleo-Asian Ocean and termination of orogeneses in the Central Asian Orogenic Belt. We identify the Baidunzi Complex, an exotic Permian transpressional continental arc terrane, characteri...

The Meelpaeg structure in southwestern Newfoundland comprises allochthonous tectonites formed during the Salinic (D1-2) and Acadian (D3) orogenies. D1-2 occurred between 451 and 417 Ma and culminated in Barrovian metamorphism during terminal collision of the Gander margin with composite Laurentia. Collision was followed by tectonic escape of the de...

The migration and character of magmatism over time can provide important insights into the tectonic evolution of an orogen. We present evidence for three separate stages of compositionally distinct granitoid magmatism associated with the Acadian orogenic cycle in the eastern and southern Newfoundland Appalachians. The interpretations are based on n...

Supplementary Material: Analytical methods and data, sample location map, field photographs and thin section photomicrographs, cathodoluminescence and backscatter images, and Concordia and kernel density estimation (KDE) plots.

Identifying source orogens for syn-orogenic sediments in dispersed fragments of a su-percontinent provides key information on the tectonic evolution of the orogens involved in supercontinent assembly and on paleogeographic reconstruction. An approach using U-Pb geochronology and trace elements of multiple detrital minerals including zircon, rutile,...

Lead isotope values for volcanogenic massive sulfide (VMS) deposits provide important insights into metal sources and the nature of pre-accretionary tectonostratigraphic terranes and underlying basements. Deposits of this type in New England formed in diverse tectonic settings including volcanic arcs and backarcs, a supra–subduction zone arc, a rif...

To understand the tectonic evolution of the Taconic eclogites, we defined the timing and metamorphic conditions of the main metamorphic stages through detailed, multiscale petro-structural analysis, thermodynamic modelling and petrochronology

Dashwoods is a composite peri-Laurentian terrane in Newfoundland forms the basement to the Early Ordovician to Silurian Notre Dame arc. The southern part of Dashwoods is characterized by paragneiss that is intruded by Early Ordovician to Late Silurian plutons and affected by polyphase Taconic to Salinic deformation and high-grade metamorphism. The...

The Beishan Orogen contains the youngest suture in the Central Asian orogenic belt and is vital to understanding its terminal collision history and closure of the last vestiges of the Paleo-Asian Ocean. Multidisciplinary evidence is provided for a close temporal and spatial linkage between the Liuyuan Complex backarc ophiolite and the Ganquan Compl...

The Bay of Islands complex, Newfoundland, Canada, represents a fossil subduction system that was obducted onto the Laurentian margin during the Taconic Orogeny. We present whole-rock geochemistry and geochronology for the Bay of Islands metamorphic sole from the Table Mountain and North Arm Mountain massifs. The Bay of Islands metamorphic sole can...

New seismic imaging by Luo et al. (2022, https://doi.org/10.1029/2022GL099013) revealed two important lithosphere‐scale structures beneath southern New England: a large offset of the Moho near the suture between Laurentia and accreted exotic terranes, and a remnant of west‐dipping slab rooted in easternmost New England. Formation of a crustal‐scale...

Located in the southern margin of the Central Asian orogenic belt, the stratigraphy and tectonic setting of the mafic 290−280 Ma Liuyuan Complex have been controversial for decades, with workers arguing for a forearc ophiolite or a continental rift setting. Here, we present the results of a detailed field study, where the Liuyuan Complex was subdiv...

A plate tectonic model involving northwesterly retreat of an Iapetan subducting slab has been developed over the last three decades to explain the time span of volcanism recorded within the development of Early Paleozoic arc systems preserved in New Brunswick. These arc systems are referred as the Penobscot arc-backarc (514–482 Ma), and Popelogan–M...

The Taconian-Grampian tract was characterized by a diachronous collision of a north-facing oceanic arc-forearc terrane and associated backarc basins with an irregular Laurentian margin with hyperextended segments. Hyperextension produced outboard continental terranes, separated by exhumed subcontinental mantle from the inboard margin. The exhumed m...

The 290-280 Ma mafic Liuyuan Complex, embedded in the terranes constituting the southern edge of the Central Asian Orogenic Belt, has been interpreted to be either an ophiolite or an intracontinental large igneous province. Our detailed mapping shows that the Liuyuan Complex preserves an almost complete oceanic crustal section, with basal troctolit...

The North American continent has a rich record of the tectonic environments and processes that occur throughout much of Earth history. This Memoir focuses on seven “turning points” that had specific and lasting impacts on the evolution of Laurentia: (1) The Neoarchean, characterized by cratonization; (2) the Paleoproterozoic and the initial assembl...

The Gubaoquan area is located in the southern part of the Palaeozoic Beishan Orogenic Collage of the Central Asian Orogenic Belt in northwest China. Structural analysis of the Gubaoquan area has documented multiple phases of deformation, which challenge previous tectonic models and suggest that the eclogites formed through in-situ metamorphism. The...

Structural and metamorphic evolution of eclogitic units of the Newfoundland Appalachians subducted and exhumed during the Taconic orogenic cycle

The results of a detailed study of thirty eclogite and amphibolite bodies embedded within gneiss and schist of the northern Fleur-de-Lys Supergroup (NFLS) in northeastern Newfoundland, eastern Canada, are presented. The NFLS represents a part of the Iapetus margin of Laurentia that was deeply buried as a result of an arc-continent collision during...

New analytical and field techniques, as well as increased international communication and collaboration, have resulted in significant new geological discoveries within the Appalachian-Caledonian-Variscan orogen. Cross-Atlantic correlations are more tightly constrained and the database that helps us understand the origins of Gondwanan terranes conti...

The eastern Dunnage Zone of the central Newfoundland Appalachians hosts Paleozoic orogenic gold mineralization along a northeast-trending, crustal-scale fault corridor that extends for more than 200 km. This orogenic gold system is characterized by polyphase, structurally controlled, quartz vein systems that cut Neoproterozoic granitoid rocks and u...

Keppie et al. (2021) presented a Devonian to Carboniferous oroclinal bending hypothesis and dextral strike-slip translation of a single arc terrane to explain the distribution of Cambrian to Ordovician volcanic rocks in the northern Appalachians. We contend that extant data are incompatible with this hypothesis for reasons documented here.

Ophiolite complexes are an important component of oceanic terranes in the northern Cordillera during Cordilleran orogenesis. Despite their tectonic importance, few systematic studies of these complexes have been conducted. Detailed studies of the pseudostratigraphy, age, geochemistry, and structural setting of ophiolitic rocks in the northern Cor...

The tectonic assembly of the Northern Cordillera is currently disputed and directly impacts Paleozoic‐to‐recent paleogeographic and plate tectonic reconstructions of North America. In this study, we present new U‐Pb zircon geochronology from the allochthonous Yukon‐Tanana terrane and the parautochthonous Cassiar terrane of the Northern Cordillera f...

West and East Ganderia in the northern Appalachians and Caledonides represent a Gondwanan superterrane situated along the Tornquist margin of Amazonia prior to Furongian drift into the Iapetus Ocean, which opened the Rheic Ocean from west to east. The ocean-facing Penobscot arc-backarc system was established by 515 Ma in West Ganderia. A correlativ...

We argue there is no distinction between accretion and collision as a process, except when accretion is used in the sense of incorporating small bodies of sedimentary and/or volcanic rocks into an accretionary wedge by off-scraping or underplating. There is also a distinction when these terms are used in classifying mountain belts into accretionary...

The Neoproterozoic tectonomagmatic evolution of West Avalonia comprises four major events. Tectonism started with the formation of a Tonian passive margin on a Baltica-derived ribbon dispersed into the Mirovoi Ocean. Obduction of an oceanic terrane onto the ribbon produced olistostromes, deformation and metamorphism before 750 Ma. Obduction was fol...

The Bathurst Mining Camp (BMC) is one of Canada’s oldest mining districts for volcanogenic massive sulphide (VMS) deposits. Most of the 46 known deposits were discovered in the 1950s using a combination of geological and geophysical methods. However, renewed exploration efforts over the past 15 years have not been as successful as one would expect...

Following Appalachian orogenesis, metamorphic rocks in central Newfoundland were exhumed and reburied under Tournaisian strata. New zircon fission‐track (ZFT) ages of metamorphic rocks below the Tournaisian unconformity yield post‐depositionally reset ages of 212–235 Ma indicating regional fluid‐absent reheating to at least ≥220°C. Post‐Tournaisian...

The Dunhuang Tectonic Belt (DTB) is located about 100 km south of the Beishan–Tianshan orogen in the Central Asian Orogenic Belt in NW China. It was previously considered as a part of the Tarim or North China craton. Detailed structural analyses reveal two episodes of deformation in the central DTB, D1 and D2. D1 is a north-side-up reverse shear, a...

Upper-plate and lower-plate settings within subduction zones have distinct geological signatures. Identifying and discriminating between these settings is crucial to the study of accretionary orogens. We applied this distinction to the Northern Cordillera in Yukon, British Columbia, and Alaska, and we focused on the identification of upper-plate an...

Upper plate and lower plate settings within subduction zones have distinct geological signatures. Identifying and discriminating between these settings is crucial to the study of accretionary orogens. We apply this distinction to the Northern Cordillera in Yukon, British Columbia and Alaska, and focus on the identification of upper plate and lower...

The Yukon Tanana (YTT) and Slide Mountain terranes (SMT) of the Cordillera in Canada and Alaska were interpreted in terms of opening and closing of a Late Devonian-Permian Japan Sea-style backarc basin behind a continental arc built upon YTT, which rifted from Laurentia during the Famennian-early Mississippian. Formation of Famennian transitional o...

The Red Indian Line (RIL) in central Newfoundland is the suture, where the main tract of the Iapetus Ocean was closed at ~452 Ma during accretion of the peri-Gondwanan Victoria arc with the composite active Laurentian margin. The protracted deformation history of this soft collision started at ~471 Ma with accretion of oceanic terranes to the activ...

The distinction of upper and lower plate processes in paleosubduction zones is critical for identification and interpretation of terrane sutures, subduction zone geometries and mechanisms of accretionary orogenesis. We utilize geochemical and geochronological analyses to challenge existing Paleozoic-Mesozoic tectonic models for the Northern Cordill...

We studied the 3-D shear-wave velocity (Vs) structure in the Gulf of St. Lawrence (GSL) and adjacent onshore areas to 20 km depth by inverting Rayleigh-wave dispersion extracted from the vertical components of continuous ambient seismic noise waveforms. The region is divided into three broad zones based on their Vs characteristics. In the northwest...

Accretionary orogens such as the NW Cordillera are often long lived and represent a collage of terranes amalgamated through multiple phases of deformation. In order to understand the early development of these orogens, key crustal components present during these early stages must be identified and studied in detail to unravel present day structural...

The Baie Verte Peninsula is located in the northern Appalachians of Newfoundland. It is underlain by the ancestral Laurentian continental margin (Humber zone), the accreted (Taconic Orogeny) Cambrian Baie Verte Oceanic Tract and its Ordovician ophiolite volcano-sedimentary cover. These three marine successions were intruded by late Ordovician to Si...

Short-lived, high-volume magmatic events or flare-ups in Cordilleran-style accretionary systems are presumably triggered by the rapid underthrusting of melt-fertile lithosphere beneath a continental arc during extreme retroarc shortening. New zircon U-Pb age and trace element geochemical studies of the Coast Mountains batholith were conducted to te...

Geochronological data from volcanic rocks aid in reconstructing the Silurian–Devonian evolution of the northern Appalachians of New Brunswick in the context of Salinic (Silurian) and Acadian (Devonian) orogenesis. Late Silurian to Early Devonian sedimentation, volcanism and deformation in northern New Brunswick is complex, and characterized by tran...

McConnell et al. (2015) claimed that the absence of Middle Ordovician back-arc volcanic rocks in the Bellewstown terrane in the Irish Caledonides implies that the Tetagouche–Exploits back-arc basin never existed in Ireland. The emphasis on the absence of evidence surprised us, because ‘absence of evidence is not evidence of absence’. However, if th...

In the New Brunswick Appalachians, polydeformed felsic volcanic rocks of the Bathurst Supergroup record four cleavage-forming tectonic events, of which D1 and D2 record subduction-related underplating of buoyant elements of the Tetagouche backarc basin and subsequent collision between composite Laurentia and the Gander margin, respectively, during...

Understanding of the formation of accretionary orogens requires investigations of the timing, kinematics and mechanisms of terrane accretion. In the NW Cordillera, the Slide Mountain oceanic terrane (SMT) formed between Phanerozoic island arcs and the North American continent (NAC) during Devonian-Permian times and subsequently recorded multiple de...

The Dunite Peak area of the Big Salmon Range, south-central Yukon, exposes klippen of maficultramafic strata belonging to the Slide Mountain terrane that structurally overlie metasedimentary strata of the Yukon-Tanana terrane. Previous workers also infer the suture between the allochthonous Yukon-Tanana terrane and parautochthonous Cassiar terrane...

The St. Cyr klippe, part of the Yukon-Tanana terrane in Yukon, Canada, preserves fresh and retrogressed eclogite hosted by quartzofeldspathic schists. Petrology, mineral chemistry and compositional zoning combined with isochemical phase equilibrium (pseudosection) modeling shows that eclogites followed a clockwise pressure-temperature path. An amph...

Knowledge of the timing, kinematics and mechanisms of terrane accretion is fundamental to our understanding of the NW Cordillera and of accretionary orogens in general. The Slide Mountain oceanic terrane (SMT) formed between Phanerozoic island arcs and the North American continent during Devonian-Permian times and subsequently recorded multiple def...

This presentation discusses the challenges for dating deformation processes recorded in rocks, and outlines the advantages and disadvantages of two approaches to 40Ar/39Ar dating, a method which calculates the age of rocks by taking advantage of the natural decay of potassium to argon over geological time scales. A case study from TGI4's volcanogen...

White mica 40Ar/39Ar analyses may provide useful constraints on the timing of tectonic processes, but complex geological and thermal histories can perturb Ar systematics in a variety of ways. Ductile shear zones represent excellent case studies for exploring the link(s) between dynamic re-/neo-crystallization of white mica and coeval enhanced fluid...

Development of an Upper Ordovician to lower Silurian (Llandovery) accretionary wedge (Brunswick subduction complex) along the composite Laurentian margin accompanied subduction of the Tetagouche backarc basin and coincided with synaccretionary sedimentation in the Bathurst and Fournier supergroups in northern New Brunswick. These dominantly turbidi...

geological map 1:50,000 scale, pdf and shape files, link: http://geoscan.nrcan.gc.ca/starweb/geoscan/servlet.starweb?path=geoscan/shorte.web&search1=R=295864

geological map, 1:50,000 scale, pdf and shape files, link: http://geoscan.nrcan.gc.ca/starweb/geoscan/servlet.starweb?path=geoscan/shorte.web&search1=R=295865

geological map, 1:50,000 scale, pdf and shape files, link: http://geoscan.nrcan.gc.ca/starweb/geoscan/servlet.starweb?path=geoscan/shorte.web&search1=R=295866

The St. Cyr area near Quiet Lake hosts well-preserved to variably retrogressed eclogite found as sub-metre to hundreds of metre-long lenses within quartzofeldspathic schist in southcentral Yukon, Canada. The St. Cyr klippe consists of structurally imbricated, polydeformed and polymetamorphosed units of continental arc crust and ultramafic-mafic roc...

A detailed tectonic analysis of the magmatic evolution of the Early to Middle Ordovician west-facing Popelogan arc in New Brunswick and adjacent Maine is presented based on combining new U-Pb zircon radiometric age dates (thermal ionization mass spectrometry and sensitive high-resolution ion microprobe) with existing age constraints on the various...

The Canadian Appalachians represent an archetypal ancient, accretionary orogen the study of which has played a substantial role in developing modern geological concepts. From the initial simplistic models of a mountain belt deriving from the closure of the Iapetus Ocean, our understanding has evolved, recognising a richer, more complex geological h...

Targeted Geoscience Initiative 4 (TGI 4) is a 5 year Government of Canada program to help produce the next generation of innovative geoscience knowledge and analytical techniques that will result in more effective targeting of buried mineral deposits. The Geological Survey of Canada in collaboration with provincial and territorial surveys, industry...

The Connaigre Peninsula of south-central Newfoundland has long been considered to be amongst the most complete and best exposed sections of Neoacadian and older Avalonian rocks in the Appalachians. The rocks of this region range from the Cryogenian volcano-sedimentaryrocks of the Tickle Point Formation (ca. 682 Ma rhyolite) to the Middle to Upper D...

The Annieopsquotch accretionary tract (AAT) comprises a thrust stack of Lower to Middle Ordovician arc and backarc terranes that were accreted to the composite Laurentian margin of Iapetus during the Middle to Late Ordovician. Geological relationships suggest that the constituent terranes of the AAT initially formed outboard of the composite Lauren...

Also published in: Reeltime geological syntheses: remembering Harold 'Hank', In J. P. Hibbard, J.C. Pollock, J. B. Murphy, C. R., van Staal, J. D. Greenough (Eds): Geological Association of Canada, Geoscience Canada reprint series 10, p. 371-394 The Baie Verte Peninsula, western Newfoundland Appalachians, preserves evidence for Early to Mid Ordovi...

40Ar/39Ar in situ UV laser ablation of white mica, Rb–Sr mineral isochrons and zircon fission track dating were applied to determine ages of very low- to low-grade metamorphic processes at 3.5±0.4 kbar, 280±30°C in the Avalonian Mira terrane of SE Cape Breton Island (Nova Scotia). The Mira terrane comprises Neoproterozoic volcanic-arc rocks overlai...

Late Paleozoic assembly of the Alexander-Wrangellia-Peninsular composite terrane is recorded by two phases of regional deformation, metamorphism, and magmatism within basement complexes of the Alexander (Craig and Admiralty subterranes), Wrangellia, and Peninsular terranes in the Canadian and Alaskan Cordillera. New secondary ion mass spectrometry...

Devonian and younger plutonic suites of the Appalachian orogen in Newfoundland form a curvilinear belt straddling the boundary between Ganderia and Avalonia, and exhibit a general pattern of younging to the southeast. However, many individual plutonic suites within this belt remain undated or have ages that are poorly constrained. This study report...

Detrital zircon populations in sedimentary rocks from the Laurentian margin and the accreted microcontinent Gan-deria on both sides of the main Iape-tus suture (Red Indian Line) in central Newfoundland have been studied by combined U–Pb and Lu–Hf isotope analyses. Variation in εHf(t) values with age of zircon populations of distal provenance (>900...

A combination of deep seismic imaging and drilling has demonstrated that the ocean-continent transition (OCT) of present-day, magma-poor, rifted continental margins is a zone of hyperextension characterized by extreme thinning of the continental crust that exhumed the lowermost crust and/or serpentinized continental mantle onto the seafloor. The OC...

Northwest-striking sinistral shear zones characterize mid-Cretaceous deformation in the western Coast Belt south of Prince Rupert in north coastal British Columbia. Structurally focused mapping and geochronology have revealed a component of lateral extension to this deformation. General flow characteristics of the shear zones are identified by comp...

We propose an intimate relationship between Silurian terrestrial red bed sedimentation (Old Red Sandstone), slab breakoff-related magmatism and deformation in the Newfoundland Appalachians. Red bed sedimentation started during the Early Silurian, and records the progressive rise of the Salinic mountains in the tectonic hinterland of the orogen. The...

Detrital zircon populations in sedimentary rocks from the Laurentian margin and the accreted microcontinent Ganderia on both sides of the main Iapetus suture (Red Indian Line) in central Newfoundland have been studied by combined U-Pb and Lu-Hf isotope analyses. Variation in epsilon Hf-(t) values with age of zircon populations of distal provenance...