Preliminary geologic map of the area of the Carlin and Blue Star gold deposits, Eureka County, Nevada

10.3133/mf552 ◽  
1974 ◽  
Keyword(s):  
2005 ◽  
Vol 24 (2) ◽  
pp. 175-196 ◽  
Author(s):  
K. Aalto

Discovery of significant gold deposits in the Black Hills, Dakota Territory, in the early 1870s led to a Congressional mandate that organized geological exploration of the Hills be undertaken. Ferdinand V. Hayden (1829-1887), who had previously visited the region, principally to collect fossils, was thwarted in his efforts to oversee such exploration by the combined efforts of John Strong Newberry (1822-1892) and John Wesley Powell (1834-1902), who instead promoted Walter P. Jenney (1850-1904?) and Henry Newton (1845-1877), both colleagues of Newberry at the Columbia College School of Mines. In a four-month field season the Jenney/Newton Survey (1875) carefully examined some 6,000 square miles of the Black Hills. Newton then oversaw production of an extensive report on the geology, mineral resources and other aspects of natural history. The report included a detailed geologic map, numerous stratigraphic columns, interpretive figures illustrating the geomorphic evolution of the Hills, thin section petrography of samples collected and a general discussion of the geologic history. Of note are Newton's interpretations of laccolith formation and drainage evolution. Despite Congressional approval funding production, the publication of the report was delayed until 1880, after Newton's untimely death in 1877 during a second visit to the Hills. It appeared under the auspices of John Wesley Powell's Geographical and Geological Survey of the Rocky Mountains Region. G. K. Gilbert (1843-1918) unofficially edited the final version of the report, using Newton's notes, drafts and figures. However, Newton should justly receive credit for its excellence.


PROMINE ◽  
2018 ◽  
Vol 6 (1) ◽  
pp. 1-11
Author(s):  
Retno Anjarwati ◽  
Arifudin Idrus ◽  
Lucas Donny Setijadji

The regional tectonic conditions of the KSK Contract of Work are located in the mid-Tertiary magmatic arc (Carlile and Mitchell, 1994) which host a number of epithermal gold deposits (eg, Kelian, Indon, Muro) and significant prospects such as Muyup, Masupa Ria, Gunung Mas and Mirah. Copper-gold mineralization in the KSK Contract of Work is associated with a number of intrusions that have occupied the shallow-scale crust at the Mesozoic metamorphic intercellular junction to the south and continuously into the Lower Tertiary sediment toward the water. This intrusion is interpreted to be part of the Oligocene arc of Central Kalimantan (in Carlile and Mitchell 1994) Volcanic rocks and associated volcanoes are older than intrusions, possibly aged Cretaceous and exposed together with all three contacts (Carlile and Mitchell, 1994) some researchers contribute details about the geological and mineralogical background, and some papers for that are published for the Beruang Kanan region and beyond but no one can confirm the genesis type of the Beruang Kanan region The mineralization of the Beruang Kanan area is generally composed by high yields of epithermal sulphide mineralization. with Cu-Au mineralization This high epithermal sulphide deposition coats the upper part of the Cu-Au porphyry precipitate associated with mineralization processes that are generally controlled by the structure


2020 ◽  
Vol 17 (1) ◽  
pp. 1-14
Author(s):  
Astra Belinda

The study of motivation has been going around in the educational field for years long, but the issue is there are not many studies that specify in reading motivation, specifically for EFL and/or ESL students. Looking upon this concern, this narrative inquiry study tried to recognize the reasons behind the reading motivation amongst the students, particularly from Blue Star Senior High School, through the Self-determination Theory (SDT) principle from Deci & Ryan (1991) and some other possible social aspects, such as family and peers. It was later found out that in general, Blue Star Senior High School’s students are more likely to be extrinsically motivated when they read and the biggest encouragement to their extrinsic motivation is their social circle. While for our main participants, their past experiences were the ones that played important roles in constructing their motivation, either intrinsically or extrinsically.


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