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Troutdale Formation

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Journal Article
Journal: GSA Bulletin
Published: 01 April 1984
GSA Bulletin (1984) 95 (4): 463–477.
... to remain in this channel through the Cascade Range. The Troutdale Formation is made up of (1) older alluvial gravels deposited below and above the Pomona intracanyon flow while the ancestral Columbia River occupied the Bridal Veil channel and (2) younger, more varied alluvial deposits characterized...
Journal Article
Published: 01 January 2000
Journal of Sedimentary Research (2000) 70 (1): 117–126.
... basins. The northwest-trending Tualatin Mountains-Portland Hills (TMPH) faulted anticline presently separates fine-grained sediments of the Hillsboro Formation in the Tualatin Basin from coarse-grained sediments of the Troutdale Formation in the Portland Basin. Augite-hornblende-hypersthene relative...
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t tests of AHH log ratios comparing the Hillsboro and <span class="search-highlight">Troutdale</span> <span class="search-highlight">formations</span> ...
Published: 01 January 2000
Table 2 t tests of AHH log ratios comparing the Hillsboro and Troutdale formations and the Willamette Silt. All tested at 0.01 level of significance.
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HBD-1 and MTD-1 stratigraphic sections comparing the lithology and age diff...
Published: 01 January 2000
Figure 4 HBD-1 and MTD-1 stratigraphic sections comparing the lithology and age differences between the Hillsboro and Troutdale formations. Sedimentation began in the late Miocene for both formations. Hillsboro Formation deposition accelerated in the Pleistocene, whereas the Troutdale Formation
Journal Article
Journal: GSA Bulletin
Published: 01 January 1952
GSA Bulletin (1952) 63 (1): 1–24.
... consequence. Northerly trending open folds were produced in the basalt with those near the axis of the Cascade Range showing the greatest effect of the compression. Contemporaneously, anticlinal highs were modified by erosion and the lower part of the Troutdale formation was deposited in downwarps along...
Journal Article
Published: 01 April 2003
Environmental & Engineering Geoscience (2003) 9 (4): 327–338.
... withdrawals. High-yield aquifers of the coarse-grained Troutdale Formation in the Portland basin contrast sharply with those of the Hillsboro Formation and Willamette Silt in that they can be separated into multiple hydrogeologic units, have high hydraulic conductivities, and can be used for municipal...
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Journal Article
Published: 01 August 2000
Environmental & Engineering Geoscience (2000) 6 (3): 279–292.
...John S. Koreny; Terry T. Fisk Abstract The Portland Basin is 900 mi 2 in size and includes portions of Oregon and Washington. A deep aquifer system of the Troutdale Formation is used for municipal ground-water supply in both states over an area of approximately 300 mi 2 . Although lateral...
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Statistical values and t tests for elements analyzed from silt and clay sed...
Published: 01 January 2000
Appendix A Statistical values and t tests for elements analyzed from silt and clay sediments in the Hillsboro Formation (HBD-1) and the Troutdale Formation (MTD-1).
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Location map of boring and stream samples used for heavy-mineral provenance...
Published: 01 January 2000
Figure 6 Location map of boring and stream samples used for heavy-mineral provenance determination of the Hillsboro Formation in the Tualatin Basin and comparison with the Troutdale Formation in the Portland area.
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Figure 2. Schematic stratigraphic and hydrostratigraphic sections of the Ne...
Published: 01 April 2003
Figure 2. Schematic stratigraphic and hydrostratigraphic sections of the Neogene basin-fill sediments in the Willamette Valley. Five hydrostratigraphic units are recognized in the coarse-grained Troutdale Formation of the Portland basin ( Swanson et al., 1993 ). The fine-grained sediments
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A)  Augite-hornblende-hypersthene (AHH) ternary plot of recent stream sedim...
Published: 01 January 2000
(> 10%) reflect erosion of the Willamette Silt. B) AHH ternary plot for Troutdale Formation sands in the Portland and Northern Willamette basins. Hypersthene abundances fluctuate widely within the same boring, suggesting that the depositional sites are influenced by multiple provenances. SRM = Sandy
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Land profile 2 across the hypothesized extension of the Portland Hills faul...
Published: 01 August 2001
distance marks. The strong, nearly horizontal reflector (large dots) may be the erosional unconformity at the base of unconsolidated sediments and top of the Troutdale Formation or it could be the water table (see text for explanation). There may be a weak reflector dipping to the east from the strong
Journal Article
Published: 01 August 2001
Bulletin of the Seismological Society of America (2001) 91 (4): 637–650.
... distance marks. The strong, nearly horizontal reflector (large dots) may be the erosional unconformity at the base of unconsolidated sediments and top of the Troutdale Formation or it could be the water table (see text for explanation). There may be a weak reflector dipping to the east from the strong...
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... of the window. The Stone Mountain fault was not recognized northeast of Troutdale, Virginia. The Shady Valley thrust sheet is continuous with the Blue Ridge thrust sheet. The ∼750 Ma Mount Rogers Formation occurs in three volcanic centers in the Blue Ridge thrust sheet. Basal clastic rocks of the lower Mount...
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Series: GSA Field Guide
Published: 01 January 2009
DOI: 10.1130/2009.fld015(13)
EISBN: 9780813756158
... of the Columbia River Basalt Group. The Columbia River has traversed the basin since its inception and delivered most of the sediment that now fills it. The older part of this fill, predating Boring volcanism, constitutes the late Miocene and Pliocene Sandy River Mudstone and Troutdale Formation ( Trimble, 1963...
Journal Article
Published: 01 August 2004
Bulletin of the Seismological Society of America (2004) 94 (4): 1402–1409.
... and Portland Hills faults east of the Willamette River in downtown Portland. The tunnel penetrates many of the lithologic units of the Portland Hills, including Columbia River basalt, Troutdale Formation, Boring Lava, and younger sedimentary deposits. It also lies below aeromagnetic anomaly AA′ and various...
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Journal Article
Journal: GSA Bulletin
Published: 01 March 2014
GSA Bulletin (2014) 126 (3-4): 271–288.
... loess and the Miocene to Pliocene Troutdale Formation, which mantles the Miocene Sentinel Bluffs unit of the Grande Ronde Basalt. The loess unit consists of quartzo-feldspathic silt, and the Troutdale Formation is a conglomerate (pebble- to cobble-sized clasts) with minor interbeds of sandstone...
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Journal Article
Journal: Geosphere
Published: 21 April 2021
Geosphere (2021) 17 (3): 804–823.
... Troutdale Formation. Clast composition suggests an extrabasinal source in pre-Cenozoic rocks in eastern Washington and Idaho ( Evarts et al., 2009 ). The upper Sandy River Mudstone was also deposited during this time, suggesting the ancestral Columbia River was a meandering system with low-energy...
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Journal Article
Journal: AAPG Bulletin
Published: 01 April 1957
AAPG Bulletin (1957) 41 (4): 643–655.
... of the Pliocene Troutdale formation in the Portland syncline of western Oregon and the absence on an adjacent structural high of a lateritic section of ferruginous bauxite developed on the underlying Miocene Columbia River basalt ( Lowry and Baldwin, 1952 ), one might be very hesitant to point out...
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Journal Article
Published: 09 July 2014
Canadian Journal of Earth Sciences (2014) 51 (8): 809–824.
... proposed based on geomorphic observations that most of the Cascades uplift occurred over during the Pliocene and Pleistocene. The Deschutes, Dalles, and upper Troutdale formations ( Fig. 1 ) consist of coarse clastic sediments that preserve remains of streamside plants that were transported by fast-flowing...
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