Detrital modes of sandstone suites primarily reflect the different tectonic settings of provenance terranes, although various other sedimentological factors also influence sandstone compositions. Comparisons of sandstone compositions are aided by grouping diverse grain types into a few operational categories having broad genetic significance. Compositional fields associated with different provenances can then be displayed on standard triangular diagrams.

Interpreting Provenance Relations from Detrital Modes of Sandstones

https://sites.williams.edu/rcox/files/2013/01/MudrockChem.pdf

The influence of sediment recycling and basement composition on evolution of mudrock chemistry in the southwestern United States

Geochemical and NdSr isotopic composition of deep-sea turbidites: Crustal evolution and plate tectonic associations

Prefaces Acknowledgements 1. Mountains and their climatological study 2. Geographical controls of mountain meteorological elements 3. Circulation systems related to orography 4. Climatic characteristics of mountains 5. Regional case studies 6. Mountain bioclimatology 7. Changes in mountain climates Appendix General index Author index.

Mountain Weather and Climate

Geochronological, structural, and sedimentological data provide the basis for a regional synthesis of the evolution of the Cordilleran retroarc thrust belt and foreland basin system in the western USA In this region, the Cordilleran orogenic belt became tectonically consolidated during Late Jurassic time ( 155 Ma) with the closure of marginal oceanic basins and accretion of fringing arcs along the western edge of the North American plate Over the ensuing 100 Myr, contractile deformation propagated approximately 1000 kilometers eastward, culminating in the formation of the Laramide Rocky Mountain ranges At the peak of its development, the retroarc side of the Cordillera was divided into five tectonomorphic zones, including from west to east the Luning-Fencemaker thrust belt; the central Nevada (or Eureka) thrust belt; a high-elevation plateau (the "Nevadaplano"); the topographically rugged Sevier fold-thrust belt; and the Laramide zone of intraforeland basement uplifts and basins Mid-crustal rocks beneath the Nevadaplano experienced high-grade metamorphism and shortening during Late Jurassic and mid- to Late Cretaceous time, and the locus of major, upper crustal thrust faulting migrated sporadically eastward By Late Cretaceous time, the middle crust beneath the Nevadaplano was experiencing decompression and cooling, perhaps in response to large-magnitude ductile extension and isostatic exhumation, concurrent with ongoing thrusting in the frontal Sevier belt The tectonic history of the Sevier belt was remarkably consistent along strike of the orogenic belt, with emplacement of regional-scale Proterozoic and Paleozoic mega- thrust sheets during Early Cretaceous time and multiple, more closely spaced, Paleo- zoic and Mesozoic thrust sheets during Late Cretaceous-Paleocene time Coeval with emplacement of the frontal thrust sheets, large structural culminations in Archean- Proterozoic crystalline basement developed along the basement step formed by Neoproterozoic rifting A complex foreland basin system evolved in concert with the orogenic wedge During its early and late history ( 155 - 110 Ma and 70 - 55 Ma) the basin was dominated by nonmarine deposition, whereas marine waters inundated the basin during its midlife ( 110 - 70 Ma) Late Jurassic basin development was controlled by both flexural and dynamic subsidence From Early Cretaceous through early Late Creta- ceous time the basin was dominated by flexural subsidence From Late Cretaceous to mid-Cenozoic time the basin was increasingly partitioned by basement-involved Laramide structures Linkages between Late Jurassic and Late Cretaceous Cordilleran arc- magmatism and westward underthrusting of North American continental lithosphere beneath the arc are not plainly demonstrable from the geological record in the Cordilleran thrust belt A significant lag-time ( 20 Myr) between shortening and coeval underthrust- ing, on the one hand, and generation of arc melts, on the other, is required for any linkage to exist However, inferred Late Jurassic lithospheric delamination may have provided a necessary precondition to allow relatively rapid Early Cretaceous continen- tal underthrusting, which in turn could have catalyzed the Late Cretaceous arc flare-up

/pdf/late-jurassic-to-eocene-evolution-of-the-cordilleran-thrust-jx3x655k2a.pdf

Late Jurassic to Eocene evolution of the Cordilleran thrust belt and foreland basin system, western U.S.A.

Systematic variations in compositional maturity of first-cycle fluvial sandstones are found in the Cutler Formation (Permian) and Fountain Formation (Permian-Pennsylvanian) in Colorado and in the Gondwana Supergroup (Permian-Triassic) of Peninsular India. These variations reflect changing climate during deposition. Climate is considered to be the critical factor affecting maturity because source rocks (granite, granite gneiss) and tectono-environmental setting (alluvial systems associated with basement-cored block uplifts) were similar and remained relatively unchanged throughout deposition of all three of the units. The roughly 3,200-m-thick Gondwana succession, consisting of five sandstone petrofacies, is characterized by the following sequence of change (oldest to youngest) in compositional maturity expressed in Q/F/R percentages: 54:42:4 88:10:2 62:34:4 82:16:2 99:1:0. This sequence is a function of the changing paleoclimate (glacial arid temperate humid warm semiarid warm semihumid warm humid) associated with the overall global limatic change and the changing latitudinal location of India as it moved from a location close to the South Pole northward during the interval of time represented by Gondwana deposition. Lithologic and fossil evidence indicates that, during deposition of the Fountain Formation, climate gradually changed from relatively wet and warm to at least semiarid and warm. This climatic change is the main factor responsible for the difference in compositional maturity of the older Fountain sandstone (Q:F:R-65:26:9) relative to the younger (Q:F:R-54:36:10). Cutler sandstone was deposited in an arid climate and has maximum compositional immaturity (Q:F:R-49:44:7). A log/log plot of the ratio of total quartz to total feldspar plus rock fragments against the ratio of total polycrystalline quartz to to al feldspar plus rock fragments is a sensitive discriminator of first-cycle sandstones with differing climatic heritage. Bulk chemical composition data support interpretation of climate from framework mineralogy, but by themselves are not sensitive enough to be unequivocal indicators. The same is true for the ZTR index and observations of degree and abundance of solution pits/embayments on detrital quartz. Results of this study support the conclusion of earlier empirical and theoretical analyses which suggest that the optimum conditions for the production and preservation of a distinctive climatic signature on sand composition are met in extensional plate-tectonic settings. Such settings are characterized by coarse-grained crystalline parent rocks, short transport distances in low-order streams, deposition in nonroutine environments, and shallow-burial diagenesis. However, even in such optimum settings, only rarely will climate be a more important determinant of sandstone composition than the tectonic setting itself.

Alluvial sandstone composition and paleoclimate; I, Framework mineralogy

Geochemical signature of provenance in sand-size material in soils and stream sediments near the Tobacco Root batholith, Montana, U.S.A.

Undulosity in quartz from low rank metamorphic rocks, as studied with a universal stage, is sufficiently different from that in pluton-derived quartz to be useful in provenance interpretation. Subdivision of monocrystalline quartz of medium sand-size into two populations, one with 5° undulosity, enables efficient and reliable interpretation. Geometrical and empirical analyses of the relation between true angles of undulosity and corresponding apparent values determined on a conventional flat stage indicate that apparent values approach real values closely enough to obviate use of the universal stage for recognition of the two quartz undulosity populations in routine petrographic analysis. The amount of polycrystalline quartz and the number of crystals per grain of polycrystalline quartz in medium-sized Holocene sand also assist in provenance interpretation. Thirteen percent of the total quartz derived from plutonic rocks is polycrystalline. This compares with 29% in sand from middle and upper-rank metamorphic rocks and 53% in sand from low-rank metamorphic rocks. Greater than 75% of the polycrystalline quartz grains from plutonic and high-rank metamorphic sources contain 2-3 crystal units per grain; less than 75% of the quartz grains from low-rank metamorphic rocks contain 2-3 crystal units. Plotting of four variables, relative percentage of (1) undulose, (2) non-undulose and (3) polycrystalline quartz, and (4) number of crystal units per polycrystalline grain, on a single diamond diagram enables one to discriminate sands of plutonic, low-rank and high-rank metamorphic parentage, both for Recent and ancient sands.

Re-evaluation of the Use of Undulatory Extinction and Polycrystallinity in Detrital Quartz for Provenance Interpretation

Holocene fluvial sands derived from the same type of crystalline parent rocks in humid-temperate and arid/semi-arid climates have distinct compositions. For a particular climate and parent rock, the similarity in composition of the fluvial sands and the sand-size fraction of soils collected from the associated interfluves indicates that climatically controlled weathering of a specific parent rock type is a primary control of sand composition. Published estimates of the magnitude of destruction of lithic fragments and feldspars associated with stream transport and deposition in a beach/coastal dune environment permit the simulation of quantitative approximations of compositional maturation of sand. For transport distances of <75 km the simulated maturation does not significantly modify the distinctive climatic imprints on composition. However, simulated maturation due to deposition in beach/coastal dune environment effectively destroys the climatic imprint. Although marine processes are highly capable of mechanically destroying lithic fragments and feldspar, our study suggests that large-scale production of first-cycle quartz arenites in such an environment is not probable. Only a rare, unique combination of extreme conditions of climate (tropical), relief (low), and sedimentation rate (slow) can give rise to first-cycle quartz arenites. Therefore we conclude that the bulk of ancient quartz arenite is multicycle in origin.

Lee J. Suttner

Papers

Alluvial sandstone composition and paleoclimate; I, Framework mineralogy

Geochemical signature of provenance in sand-size material in soils and stream sediments near the Tobacco Root batholith, Montana, U.S.A.

Re-evaluation of the Use of Undulatory Extinction and Polycrystallinity in Detrital Quartz for Provenance Interpretation

Climate and the origin of quartz arenites

The effect of grain size on detrital modes; a test of the Gazzi-Dickinson point-counting method; discussion and reply