• Journal of the Korean Geophysical Society
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• v.2 no.3
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• pp.169-178
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• 1999

Low-field anisotropy of magnetic susceptibility (AMS) was measured with 247 samples from 17 sites of Pre-Cambrian anorthositic rocks in the Hadong-Sanchong area, southwestern part of the Ryongnam Block. Tectonic stress-direction is defined by the minimum susceptibility (k3) direction, and flow-direction by the maximum susceptibility (k1) direction. Five sites rendered self-consistent NW-SE site-mean tectonic stress-direction. Even though a general fold test for every site was not possible due to the homoclinal nature of the bedding attitudes, a site with various bedding attitudes shows far better clustering of the k3-direction before the bedding-tilt correction. The in-situ NW-SE tectonic stress-direction is consistent over the study area and compatible with petrographic foliation observed in metamorphic rocks in and arround the study area, suggesting a regional compressive force acted after the emplacement of the anorthositic rocks. On the other hand, flow-directions obtained from six sites varies from site to site. Strong-field IRM experiments show predominance of titanomagnetites over a small amount of hematite in some samples.

• Journal of the Mineralogical Society of Korea
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• v.5 no.1
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• pp.14-21
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• 1992

Allanite crystals rich in rare-earth elements(REE) occur in soil developed on top of anorthositic rocks in the Jungsu-ri area of Okjong-myun, Hadong-run, where large Ti orebodies are embedded in the bed rock. In this study allanite is investigated mainly by transmitted light microscopy, electron microprobe analysis, atomic absoption spectrophotometry, X-ray diffraction, infrared spectrocopy. In addition, its specific gravity and micro=indentation hardness value are measured. Allanite occurs with max. dimension of $3cm{\times}6cm$ and coexists with quartz, epidote, zircon, biotite and muscovite. It shows nearly nonmetamict crystallinity, although ${\alpha}$-particles bombardment from the disintegration of the radioactive element Th is detected by an autoradiography. The allanite is particularly enriched in REE(19.88-23.99 wt.%), but is deficient in CaO(8.35-10.29wt.%). Genesis of the allanite in this area is not understood yet. It is, however, assumed to have been formed from magmatic fluid rich in REE and Ti, based on the facts that it ocexists with zircon and that it has high $TiO_2$(0.89-1.13 wt.%) whose concentration is significant in the country rocks.

• Journal of the Korean Geographical Society
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• v.34 no.1
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• pp.47-61
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• 1999

The purpose of this study is to grasp position of Sachon airport-local airport-especially the characteristics of it's air passengers, the distribution of passengers hinterland on their purposes of the travel and on the day of the week, and the spatial structure of hinterland The results is as follows The distribution of the hinterland on the purposes of a passenger's travel shows the hunterland of friend and acquauntance visit is wider than that of business, And the middle level of its size is sightseeing The hinterland of commuting includes only Chinju, so the range of passengers' social activities is wider than that of passenger' economic activities In the distribution of the hunterland on the day of the week, the distnbution of the weekday is wider than that of the holidays, but the passenger travel to Chinju is concentrated on the holidays. As rnentioned adove, the hinterland centenng around Sachon airport is Chinju sity field. Tongyoung. Sachon and Koje city field, Kwangyang city and Namhae, Sanchong, Kosung, Hadong, Uiryoung county field. It is a little different result from the area of reverse commuting of the elementray, middle and high school Leachers living in Chinju That's because air passenger travel mainly occurs in industrial and sighrseeing cities