Geology and Ore Deposits of the Clinton Mining District

This report includes the results of geological investigation of the Clinton Mining District and the Hidden Treasure Mine.The Clinton Mining District is an unorganized mining dis­trict situated in the Garnet Range two and one-half miles northeast of the town of Clinton, Montana, which is on the Northern Pacific Railway and the Chicago, Milwaukee, St. Paul, and Pacific Railroad seventeen miles east of the city of Missoula. The district is in the same range of mountains as the Gar­net Mining District and the drainage from the district covered is to the south into the Hell Gate or Clarks Fork of the Colum­bia River. The main stream is known as Trail creek, which runs in a southerly direction from the area studied.

General Geology and Mines of Northwestern Montana

The five counties discussed in this paper compose the northernmost and westernmost counties in Montana. On the eastern boundary are Glacier National Park and the Continental Divide; on the southern boundary are Missoula and Powell counties; Idaho lies on the southwestern and western side; and the Canadian border lies along the northern edge. The region is on the Pacific Ocean side of the Rocky Mountains. Three major rivers, the Clark Fork, the Flathead, and the Kootenai drain this area into the Columbia River.

Satellite-Derived Variability in Chlorophyll, Wind Stress, Sea Surface Height, and Temperature in the Northern California Current System

Satellite-derived data provide the temporal means and seasonal and nonseasonal variability of four physical and biological parameters off Oregon and Washington ( 41 degrees - 48.5 degrees N). Eight years of data ( 1998 - 2005) are available for surface chlorophyll concentrations, sea surface temperature ( SST), and sea surface height, while six years of data ( 2000 - 2005) are available for surface wind stress. Strong cross-shelf and alongshore variability is apparent in the temporal mean and seasonal climatology of all four variables. Two latitudinal regions are identified and separated at 44 degrees - 46 degrees N, where the coastal ocean experiences a change in the direction of the mean alongshore wind stress, is influenced by topographic features, and has differing exposure to the Columbia River Plume. All these factors may play a part in defining the distinct regimes in the northern and southern regions. Nonseasonal signals account for similar to 60 - 75% of the dynamical variables. An empirical orthogonal function analysis shows stronger intra-annual variability for alongshore wind, coastal SST, and surface chlorophyll, with stronger interannual variability for surface height. Interannual variability can be caused by distant forcing from equatorial and basin-scale changes in circulation, or by more localized changes in regional winds, all of which can be found in the time series. Correlations are mostly as expected for upwelling systems on intra-annual timescales. Correlations of the interannual timescales are complicated by residual quasi-annual signals created by changes in the timing and strength of the seasonal cycles. Examination of the interannual time series, however, provides a convincing picture of the covariability of chlorophyll, surface temperature, and surface height, with some evidence of regional wind forcing.

Geochemistry, isotopic ratios and mineral composition of samples from ODP Leg 163 sites

Thirty-five samples from the drill core of the three Leg 163 sites (Sites 988, 989, and 990) off the southeast coast of Greenland were analyzed for 27 major, minor, and trace elements by X-ray fluorescence (XRF) and for 25 trace elements, including 14 rare-earth elements (REEs), by an inductively coupled plasma source mass spectrometer (ICP/MS). Sr- and Nd-isotope data are reported for seven samples and oxygen-isotope data are reported for 19 plagioclase separates. In addition, a reconnaissance survey of the composition of the main mineral phases, plagioclase, pyroxene, and oxides was determined on an electron microprobe to provide the basic information required for petrogenetic modeling. Olivine pseudomorphs are present in many of the samples, but in no case was an olivine grain found that was fresh enough to give a reliable analysis. The chemical and isotopic data recorded here were determined to provide a comparison with the larger data sets acquired by the Edinburgh, Copenhagen, and Leicester laboratories from both Legs 152 and 163 drill cores. This will permit a detailed comparison of the North Atlantic flood basalt province as a whole with the better known Columbia River, Deccan, and Karoo continental flood basalt provinces, for which substantial chemical data sets are already available at Washington State University.

Isotopic and chemical compositions of DSDP site 18-174 sediments

The Astoria submarine fan, located off the coast of Washington and Oregon, has grown throughout the Pleistocene from continental input delivered by the Columbia River drainage system. Enormous floods from the sudden release of glacial lake water occurred periodically during the Pleistocene, carrying vast amounts of sediment to the Pacific Ocean. DSDP site 174, located on the southern distal edge of the Astoria Fan, is composed of 879 m of terrigenous sediments. The section is divided into two major units separated by a distinct seismic discontinuity: an upper, turbidite fan unit (Unit I), and an underlying finer-grained unit (Unit II). Both units have overlapping ranges of Nd and Hf isotope compositions, with the majority of samples having e-Nd values of -7.1 to -15.2 and eHf values -6.2 to -20.0; the most notable exception is the uppermost sample in the section, which is identical to modern Columbia River sediment. Nd depleted mantle model ages for the site range from 2.0 to 1.2 Ga and are consistent with derivation from cratonic Proterozoic source regions, rather than Cenozoic and Mesozoic terranes proximal to the Washington-Oregon coast. The Astoria Fan sediments have significantly less radiogenic Nd (and Hf) isotopic compositions than present day Columbia River sediment (e-Nd=-3 to -4; [Goldstein, S.J., Jacobsen, S.B., 1987. Nd and Sr isotopic systematics of river water suspended material: implications for crustal evolution. Earth. Planet. Sci. Lett. 87, 249-265; doi:10.1016/0012-821X(88)90013-1]), and suggest that outburst flooding, tapping Proterozoic source regions, was the dominant sediment transport mechanism in the genesis and construction of the Astoria Fan. Pb isotopes form a highly linear 207Pb/204Pb - 206Pb/204Pb array, and indicate the sediments are a binary mixture of two disparate sources with isotopic compositions similar to Proterozoic Belt Supergroup metasediments and Columbia River Basalts. The combined major, trace and isotopic data argue that outburst flooding was responsible for depositing the majority (top 630 m) of the sediment in the Astoria Fan.

Biogenic sedimentation of DSDP Site 85-574

The equatorial Pacific is an important part of the global carbon cycle and has been affected by climate change through the Cenozoic (65 Ma to present). We present a Miocene (12-24 Ma) biogenic sediment record from Deep Sea Drilling Project (DSDP) Site 574 and show that a CaCO3 minimum at 17 Ma was caused by elevated CaCO3 dissolution. When Pacific Plate motion carried Site 574 under the equator at about 16.2 Ma, there is a minor increase in biogenic deposition associated with passing under the equatorial upwelling zone. The burial rates of the primary productivity proxies biogenic silica (bio-SiO2) and biogenic barium (bio-Ba) increase, but biogenic CaCO3 decreases. The carbonate minimum is at ~17 Ma coincident with the beginning of the Miocene climate optimum; the transient lasts from 18 to 15 Ma. Bio-SiO2 and bio-Ba are positively correlated and increase as the equator was approached. Corg is poorly preserved, and is strongly affected by changing carbonate burial. Terrestrial 232Th deposition, a proxy for aeolian dust, increases only after the Site 574 equator crossing. Since surface production of bio-SiO2, bio-Ba, and CaCO3 correlate in the modern equatorial Pacific, the decreased CaCO3 burial rate during the Site 574 equator crossing is driven by elevated CaCO3 dissolution, representing elevated ocean carbon storage and elevated atmospheric CO2. The length of the 17 Ma CaCO3 dissolution transient requires interaction with a 'slow' part of the carbon cycle, perhaps elevated mantle degassing associated with the early stages of Columbia River Basalt emplacement.

Spherules and basement analyses from DSDP Hole 5-32

Lower Miocene basaltic glass spherules from DSDP Site 32 pelagic sediments in the eastern Pacific are compositionally diverse, and new analyses and interpretations have been added to those of earlier workers. The spherules are of titanian ferrobasalt which is compositionally similar to highly evolved abyssal basalts and to some oceanic island eruptives, and they were most likely shaped during intense lava fountaining during a number of separate eruptions. These eruptions tapped distinct but related magma batches in terms, for example, of distinctively high TiO2 and FeO* contents. Their age overlaps that of some of the eruptions of the Columbia River Plateau Basalts, but they are compositionally distinct from most of the latter basalts. Although about 15 m.y. old, they show little alteration. The low chlorine and sulfur contents compared to those of abyssal ferrobasalts are consistent with degassing prior to quenching during subaerial eruptions, and rule out production of the spherules by submarine fountaining. Lava fountaining alone is insufficient to account for the distance of about 100 km from even the closest possible seamount source. Instead, large phreatomagmatic eruption columns reaching at least 15 km and including lava fountaining immediately after the initial explosion are required. Alternatively, and deemed less likely, is their deposition by turbidites derived from Pioneer Seamount.

Miocene strontium isotope record of DSDP Hole 30-289

A composite strontium isotopic seawater curve was constructed for the Miocene between 24 and 6 Ma by combining 87Sr/86Sr measurements of planktonic foraminifera from Deep Sea Drilling Project sites 289 and 588. Site 289, with its virtually continuous sedimentary record and high sedimentation rates (26 m/m.y.), was used for constructing the Oligocene to mid-Miocene part of the record, which included the calibration of 63 biostratigraphic datums to the Sr seawater curve using the timescale of Cande and Kent (1992 doi:10.1029/92JB01202). Across the Oligocene/Miocene boundary, a brief plateau occurred in the Sr seawater curve (87Sr/86Sr values averaged 0.70824) which is coincident with a carbon isotopic maximum (CM-O/M) from 24.3 to 22.6 Ma. During the early Miocene, the strontium isotopic curve was marked by a steep rise in 87Sr/86Sr that included a break in slope near 19 Ma. The rate of growth was about 60 ppm/m.y. between 22.5 and 19.0 Ma and increased to over 80 ppm/m.y. between 19.0 and 16 Ma. Beginning at ~16 Ma (between carbon isotopic maxima CM3 and CM4 of Woodruff and Savin (1991 doi:10.1029/91PA02561)), the rate of 87Sr/86Sr growth slowed and 87Sr/86Sr values were near constant from 15 to 13 Ma. After 13 Ma, growth in 87Sr/86Sr resumed and continued until ~9 Ma, when the rate of 87Sr/86Sr growth decreased to zero once again. The entire Miocene seawater curve can be described by a high-order function, and the first derivative (d87Sr/86Sr/dt) of this function reveals two periods of increased slope. The greatest rate of 87Sr/86Sr change occurred during the early Miocene between ~20 and 16 Ma, and a smaller, but distinct, period of increased slope also occurred during the late Miocene between ~12 and 9 Ma. These periods of steepened slope coincide with major phases of uplift and denudation of the Himalayan-Tibetan Plateau region, supporting previous interpretations that the primary control on seawater 87Sr/86Sr during the Miocene was related to the collision of India and Asia. The rapid increase in 87Sr/86Sr values during the early Miocene from 20 to 16 Ma imply high rates of chemical weathering and dissolved riverine fluxes to the oceans. In the absence of another source of CO2, these high rates of chemical weathering should have quickly resulted in a drawdown of atmospheric CO2 and climatic cooling through a reversed greenhouse effect. The paleoclimatic record, however, indicates a warming trend during the early Miocene, culminating in a climatic optimum between 17 and 14.5 Ma. We suggest that the high rates of chemical erosion and warm temperatures during the climatic optimum were caused by an increase in the contribution of volcanic CO2 from the eruption of the Columbia River Flood Basalts (CRFB) between 17 and 15 Ma. The decrease in the rate of CRFB eruptions at 15 Ma and the removal of atmospheric carbon dioxide by increased organic carbon burial in Monterey deposits eventually led to cooling and increased glaciation between ~14.5 and 13 Ma. The CRFB hypothesis helps to explain the significant time lag between the onset of increased rates of organic carbon burial in the Monterey at 17.5 Ma (as marked by increased delta13C values) and the climatic cooling and glaciation during the middle Miocene (as marked by the increase in delta18O values), which did not begin until ~14.5 Ma.

Strontium-90 and tritium concentrations in surface waters of the North Pacific

Results of determinations of 90Sr and tritium polluting surface water in different parts of the North Pacific are presented. The T/90Sr ratio lies within 90-600 over the referred water area and attains 2000 near the Columbia River mouth. Tritium concentration in sea water has been noted to be affected by river runoff and terrigenous sediments.

Grain counts and XRD mineralogy of turbidite sand and hemipelagic mud from ODP Leg 168 sites

Sequences of late Pliocene to Holocene sediment lap onto juvenile igneous crust within 20 km of the Juan de Fuca Ridge in northwestern Cascadia Basin, Pacific Ocean. The detrital modes of turbidite sands do not vary significantly within or among sites drilled during Leg 168 of the Ocean Drilling Program. Average values of total quartz, total feldspar, and unstable lithic fragments are Q = 35, F = 35, and L = 30. Average values of monocrystalline quartz, plagioclase, and K-feldspar are Qm = 46, P = 49, and K = 5, and the average detrital modes of polycrystalline quartz, volcanic-rock fragments, and sedimentary-rock plus metamorphic-rock fragments are Qp = 16, Lv = 43, and Lsm = 41. Likely source areas include the Olympic Peninsula and Vancouver Island; sediment transport was focused primarily through the Strait of Juan de Fuca, Juan de Fuca Channel, Vancouver Valley, and Nitinat Valley. Relative abundance of clay minerals (<2-µm-size fraction) fluctuate erratically with depth, stratigraphic age, and sediment type (mud vs. turbidite matrix). Mineral abundance in mud samples are 0%-35% smectite (mean = 8%), 18%-59% illite (mean = 40%), and 29%-78% chlorite + kaolinite (mean = 52%). We attribute the relatively low content of smectite to rapid mechanical weathering of polymictic source terrains, with little or no input of volcanic detritus from the Columbia River. The scatter in clay mineralogy probably was caused by converging of surface currents, turbidity currents, and near-bottom nepheloid clouds from several directions, as well as subtle changes in glacial vs. interglacial weathering products.

Radiocarbon data, oxygen isotopic composition in foraminifera, freshwater diatoms data, and salinity estimations from ODP Holes 167-1019C and 167-1019D

Massive discharges of freshwater from the glacial lake Missoula to the northeast Pacific Ocean are thought to have sculpted the Channeled Scablands of eastern Washington and debouched via the Columbia River near 46°N. The dynamics and timing of these events and their impact on northeast Pacific circulation remain uncertain. Here we date marine records of anomalous freshwater inputs to the ocean based on freshwater diatoms, oxygen isotopes in foraminifera, and radiocarbon data. Low-salinity plumes from the Columbia River reduced sea-surface salinities by as much as 6 psu (practical salinity units) more than 400 km away between 16 and 31 cal (calendar) ka B.P. Anomalously high abundances of freshwater diatoms in marine sediments from the region precede generally accepted dates for the existence of glacial Lake Missoula, implying that large flooding or freshwater routing events were common during the advance of the Cordilleran Ice Sheet and that such events require multiple sources.

Review of power planning in the Pacific Northwest.

Vols. for 1961- cover calendar year.

The Timberman.

"An international lumber journal."

Report of the Board of commissioners of canals and locks of the state of Oregon to the Twenty-third Legislative assembly [regular session] 1905 ...

Report concerning canal between the Dalles and Celilo, for improvement of channel of the Columbia river.