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James E. Quick

Publications and source records attributed to James E. Quick.

16 recordsLinked to original sources

Neoproterozoic tectonic evolution of the Jebel Saghro and Bou Azzer - El Graara inliers, eastern and central Anti-Atlas, Morocco

New mapping, geochemistry, and 17 U–Pb SHRIMP zircon ages from rocks of the Sirwa, Bou Azzer–El Graara, and Jebel Saghro inliers constrain the Neoproterozoic evolution of the eastern Anti-Atlas during Pan-African orogenesis. In the Sirwa inlier, Tonian quartzite from the pre Pan-African passive margin deposits of the Mimount Formation contains detrital zircon derived entirely from the West African Craton (WAC), with most grains yielding Eburnean Paleoproterozoic ages of about 2050 Ma. Cryogenian Pan-African orogenic activity (PA1) from about 760 to 660 Ma included northward-dipping subduction to produce a volcanic arc, followed by ophiolite obduction onto the WAC. In the Bou Azzer–El Graara inlier, calc-alkaline granodiorite and quartz diorite, dated at 650–646 Ma, are syn- to post-tectonic with respect to the second period of Pan-African orogenesis (PA2), arc-continent accretion, and related greenschist facies metamorphism. Slab break-off and lithospheric delimination may have provided the source for the supra-subduction calc-alkaline plutons. At about 646 Ma, quartz diorite intruded the Tiddiline formation placing an upper limit on molassic deposition. Widespread Ediacaran high-K calc-alkaline to shoshonitic plutonism and volcanism during the final stage of Pan-African orogenesis (PA3) occurred in a setting related to either modification of the margin of the WAC or formation of a continental volcanic arc above a short-lived southward-dipping subduction zone. In the Saghro inlier, eight plutonic rocks yield ages ranging from about 588 to 556 Ma. Sampled plutonic rocks previously considered to be Cryogenian yielded Ediacaran ages. Peraluminous rhyolitic volcanic rocks in the lower part of the Ouarzazate Supergroup, including ash-flow tuffs of the Oued Dar’a caldera, yield ages between about 574 and 571 Ma. The Oued Dar’a caldera developed in a pull-apart graben produced by a left-step in a northeast-trending, left-lateral strike-slip fault zone, and much of the lower Ouarzazate Supergroup volcanic rocks in the area are probably related to caldera out-flow facies and collapse. Late stage PA3 intrusive rocks include the Bouskour–Sidi Flah and Timijt rhyolitic dike swarms at about 563 Ma, the voluminous pink Isk-n-Alla granite (559 ± 5 Ma), and volumetrically minor gabbro of Tagmout (556 ± 5 Ma). Rhyolite flows from the upper part of the Ouarzazate Supergroup, above a regional angular unconformity, yielded ages of 558 ± 4 and 556 ± 4 Ma. The youngest ages place an upper limit on block faulting and weak folding during latest Pan-African tectonic activity (PA3), coincident with the departure of the Cadomian crustal fragment from the northern margin of the WAC.

Precambrian Research↗

Hydrogen and oxygen isotope constraints on hydrothermal alteration of the Trinity peridotite, Klamath Mountains, California

The Trinity peridotite represents a rare opportunity to examine a relatively fertile plagioclase peridotite that was exhumed and later subjected to intrusive events in a seafloor environment, followed by its emplacement and incorporation into a continent. Over 250 stable isotopic determinations on whole rocks and minerals elucidate the hydrothermal evolution of the Trinity complex. All three serpentine polymorphs are present in the Trinity peridotite; these separate on the basis of their δD values: antigorite, -46 < δD < -82‰ and lizardite and chrysotile, -90 < δD < -106 and -110 < δD < -136‰, respectively. Antigorite coexists with chlorite, talc, and tremolite in contact aureole assemblages associated with Silurian/Devonian gabbroic plutons. Lizardite and chrysotile alteration carries a meteoric signature, which suggests association with post-emplacement serpentinization, or overprinting of earlier low-temperature seafloor serpentinization. Regionally, contours of δD values exhibit bull's-eye patterns associated with the gabbroic plutons, with δD maxima coinciding with the blackwall alteration at the margins on the plutons. In contrast to the hydrogen isotope behavior, oxygen isotope values of the three polymorphs are indistinguishable, spanning the range 5.3 < δ 18 O< 7.5, and suggesting low integrated fluid fluxes and strongly 18 O-shifted fluids. Inferred primary δ 18 O values for peridotite, gabbro, and late Mesozoic granodiorite indicate a progressive 18 O enrichment with time for the source regions of the rocks. These isotopic signatures are consistent with the geology, petrochemistry, and geochronology of the Trinity massif, which indicate the following history: (1) lithospheric emplacement and cooling of the peridotite in an oceanic environment ~472 Ma; (2) intrusion of gabbroic plutons into cold peridotite in an arc environment between 435 and 404 Ma; and finally (3) intrusion of felsic plutons between 171 and 127 Ma, long after the peridotite was incorporated into the continental crust.

California↗

Constraints on the size, overpressure, and volatile content of the Mount St. Helens magma system from geodetic and dome-growth measurements during the 2004-2006+ eruption

During the ongoing eruption at Mount St. Helens, Washington, lava has extruded continuously at a rate that decreased from ~7-9 m 3 /s in October 2004 to 1-2 m 3 /s by December 2005. The volume loss in the magma reservoir estimated from the geodetic data, 1.6-2.7×10 7 m3 , is only a few tens of percent of the 7.5×10 7 m 3 volume that had erupted by the end of 2005.

Washington↗

SUPERXAP manual

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Open-File Report↗

Geology of the Bir Nifazi Quadrangle, Kingdom of Saudi Arabia

The Bi'r Nifazi quadrangle is located in the north-central part of the Precambrian shield of Saudi Arabia between lat 24&deg; 45' and 25&deg; 00' N. and long 41&deg; 15' and 41&deg; 30' E. Approximately 75 percent of the area is underlain by large plutons that range in composition from gabbro to alkali granite. A nearly complete ophiolitic section, the Darb Zubaydah ophiolite, is preserved in septa between and in roof pendants within these plutons. The ophiolite appears to comprise the oldest rocks in the area. The age of the ophiolite (800-840 Ma) is based on a tentative correlation with dated volcanic rocks in the Nuqrah area, approximately 100 km north of the Bi'r Nifazi area. Emplacement of younger plutons has rotated the ophiolitic section into an eastward-facing subvertical homocline. The lowest exposed unit in the ophiolite within the quadrangle is composed of serpentinized peridotite that is intruded by gabbro and diabase dikes. The serpentinite is overlain by gabbro and microgabbro, massive diabase, a lower basalt sequence, a thick sandstone sequence named the Kaffan sandstone, lahar deposits, an upper basalt sequence, and interbedded tuff, basalt, and sedimentary rocks. Tectonized peridotite is not present at the base of the ophiolite, but roof pendants of tectonized peridotite are present in the granodiorite batholith west of the Bi'r Nifazi quadrangle. The composition of volcanic rocks and the abundance of pillow basalt, volcanic wacke, and coarse-grained andesitic to rhyolitic tuff and volcaniclastic rocks suggest that the ophiolite formed in the vicinity of an island arc. Strands of the left-lateral Najd fault system cut all of the ophiolitic and plutonic rocks and bound small basins in which sedimentary rocks of the Jibalah group were deposited. A north-trending, 10-km-long belt of gossans crops out within the ophiolite beneath the upper-basalt sequence at Jabal Mardah. Reconnaissance drilling indicates that one of the larger gossans is underlain by a steeply dipping, 15-m-thick, sulfide-rich volcanic wacke that averages 1 percent nickel locally. The ore is composed of pyrite, millerite, polydymite, and minor sphalerite that fill interstices between clasts of the wacke and are intimately intergrown with quartz and nickel-rich epidote and chlorite. These textures and assemblages suggest that the sulfides crystallized in situ from infiltrating hydrothermal fluids. Tuffs and basalt flows appear to have acted as impermeable barriers that channeled the hydrothermal fluids through the more permeable wacke where sulfides were deposited. Carbonate-replaced serpentinized peridotite at the base of the ophiolite is considered a potential source for the nickel. In contrast to most nickel deposits, the mineralized rocks at Jabal Mardah have extremely high Ni/Cu (130 to 260) and negligible concentrations (< 5 ppb) of platinum-group elements.

Open-File Report↗

SAVEWARE I; a dozen programs designed to read DATASAVE files, perform various petrologic calculations, and produce printed and graphical data analysis, Part A - Documentation

SAVEWARE is a group of 12 programs that run on IBM and IBM compatible microcomputers. The programs were written in QuickBASIC and have been combined with input/output routines from DATASAVE. The programs (except ASCI2DSV) access data from DATASAVE format data files and perform various petrologic operations.

Open-File Report↗

XAP, a program for deconvolution and analysis of complex X-ray spectra

The X-ray analysis program (XAP) is a spectral-deconvolution program written in BASIC and specifically designed to analyze complex spectra produced by energy-dispersive X-ray analytical systems (EDS). XAP compensates for spectrometer drift, utilizes digital filtering to remove background from spectra, and solves for element abundances by least-squares, multiple-regression analysis. Rather than base analyses on only a few channels, broad spectral regions of a sample are reconstructed from standard reference spectra. The effects of this approach are (1) elimination of tedious spectrometer adjustments, (2) removal of background independent of sample composition, and (3) automatic correction for peak overlaps. Although the program was written specifically to operate a KEVEX 7000 X-ray fluorescence analytical system, it could be adapted (with minor modifications) to analyze spectra produced by scanning electron microscopes, electron microprobes, and probes, and X-ray defractometer patterns obtained from whole-rock powders.

Open-File Report↗

DATASAVE manual

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Open-File Report↗

DATASAVE manual

Explore the source record for details and available documents.

Open-File Report↗

Geology of the Wadi Ash Shu'bah Quadrangle, Sheet 26 E, Kingdom of Saudi Arabia

The Wadi Ash Shu'bah quadrangle, located in the north-central part of the Arabian Shield, is underlain by nine Precambrian volcano-sedimentary formations and a wide compositional range of Precambrian intrusive rocks. Late Proterozoic to early Paleozoic rocks of the Jibalah Group crop out in the southwestern part of the quadrangle. Paleozoic and younger units are limited to the early Paleozoic Siq Sandstone that crops out in the northwestern part of the quadrangle and small outcrops of Cenozoic basalt and unconsolidated Quaternary sediments. The Hulayfah group, dated at older than 738 Ma, is the oldest volcano-sedimentary unit in the quadrangle and consists of metamorphosed basaltic to andesitic volcanic and subvolcanic rock, and interbedded limestone, sandstone, and silicic volcanic rock. The Maraghan formation is composed of strongly folded, fine-grained sedimentary rock that was deposited between 677 and 621 Ma. The Hadn and Hibshi formations are composed of rhyolitic to rhyodacitic volcanic rock and interbedded continental sedimentary rock that were deposited between 651 and 600 Ma, but are inferred to postdate the Maraghan formation because they are significantly less deformed. Andesitic flows and volcanic breccia in the southeast corner of the quadrangle are mapped as the Jurdhawiyah group; these rocks unconformably overlie the Maraghan formation. The Zarghat formation is a thick sequence of interbedded sedimentary rock and silicic volcanic rock, and unconformably overlies the Hadn formation. It is inferred to have been deposited between 600 and 580 Ma. The Precambrian igneous rocks are organized into four tentative magmatic episodes. Greenstone of the Hulayfah group and dioritic intrusive rocks represent the oldest episode, and are believed to have formed in an ensimatic magmatic arc environment. These rocks were intruded during a second magmatic episode by post-Hulayfah monzogranite and granodiorite. A still younger, post-Hadn magmatic episode is represented by alkali-feldspar granite and syenogranite. The most recent magmatic episode is represented by small diabase and gabbro intrusions that are inferred to have been emplaced during a period of crustal rifting coincident with the deposition of the Jibalah group. The magnesite deposit near the village of Zarghat is the most significant mineral deposit in the quadrangle. However, the Hulayfah group has the most potential for metallic deposits in the area as it contains numerous gossans and ancient mine workings.

Open-File Report↗

Reconnaissance geology of the Ghazzalah Quadrangle, sheet 26/41 A, Kingdom of Saudi Arabia

The Ghazzalah quadrangle is located in the northern Precambrian shield of Saudi Arabia between lat 26?30' and 27?00' N. and long 41?00' and 41?30' E. The area is underlain by two lithologically distinct, Precambrian volcanosedimentary units and a wide range of dioritoid and granitoid plutonic intrusive rocks. The only Phanerozoic rocks consist of one outcrop of Tertiary(?) basalt and widespread but thin deposits of Quaternary detritus. The Banana greenstone, the oldest rock in the quadrangle, consists of intermediate volcanic and subvolcanic rocks and minor interbedded marble, which have been metamorphosed to greenschist-facies assemblages. Volcanic rocks mainly range in composition from basalt to andesite, and subvolcanic rocks consist of diorite and diabase. The Banana greenstone is unconformably overlain by silicic volcanic rocks and minor arkosic sandstone and breccia of the Hadn formation. Preservation of delicate volcanic textures suggests that the rocks have been only incipiently metamorphosed. Unpublished rubidium/strontium isotopic data for the Hadn formation suggest an age of 620 to 610 Ma. Intrusive rocks are separable according to their ages relative to the Hadn formation. Those that are unconformably overlain by the Hadn formation consist of hornblende quartz diorite and gabbro, which may be consanguineous with the Banana greenstone, and younger tonalite, biotite-hornblende granodiorite, syenogranite, and monzogranite. Plutons of monzogranite, alkali-feldspar g,ranite, syenbgranite, peralkaline granite, and hypabyssal intrusions of granophyre were probably emplaced during a period coincident with and (or) following Hadn volcanism. Uranium-lead and rubidium/strontium isotopic data for two plutons in the adjacent Al Qasr quadrangle suggest that plutonic activity persisted in the region until about 580 to 570 Ma. Faulting appears to postdate all of the plutonic rocks. The dominant faults belong to a northeast-trending system of right-lateral shears; a subordinant system consists of mainly north- to northwest-trending faults. The peralkaline-granite plutons underlying Jibal Ba'gham and Jibal ar Rumman have the most economic potential. Wadi samples from these areas show an anomalous concentrations of tin, lead, niobium, and yttrium. Localized, intense radiometric anomalies in the Ba'gham intrusive complex are associated with high concentrations )f thorium, uranium, andrare-earth elements.

Open-File Report↗