• Korean journal of applied entomology
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• v.14 no.3 s.24
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• pp.97-109
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• 1975

In an attempt to develop an effective integrated system of controlling blast disease of rice caused by Pyricularia oryzae Cav., the possibility of minimizing the disease incidence by proper application of fertilizers has been investigated. Thus the effect of silicate, nitrogen, phosphorus and potassium fertilizers on the development of blast disease as well as the correlation between the rice varieties an4 strains of P. oryzae were studied. The experiments were made in 1971 and 1973 by artificial inoculation and under natural development of the blast disease on rice plants. The results obtained are summarized as follows. 1. Application of silicate fertilizer resulted in the increase of silicate as well as total sugar and potassium content but decrease of total nitrogen and phosphorus in tile leaf blades of rice plants. 2. The ratios of total C/total N. $ SiO_2/total$ N, and $K_2O/total$ N in leaf blades of rice plants increased by the application of silicate fertilizers. There was high level of negative correlation between the ratios mentioned above and the incidence of rice blast disease. 3. Application of silicate fertilizer reduced the incidence of rice blast disease. 4. The over dressing of nitrogen fertilizer resulted in the increase of total nitrogen and decrease of silicate and total sugar content in leaf blades, thus disposing the rice plants more susceptible to blast disease. 5. Over dressing of phosphorus fertilizer resulted in the increase of both total nitrogen and Phosphorus, and decrease of silicate content in the leaf blades inducing the rice plants to become more susceptible to blast disease. 6. Increased dressing of potash resulted in the increase of silicate content and $K_2O/total$ N ratio but decrease of total nitrogen content in leaf blades. When potassium content is low in the leaf blades of rice plants, the additional dressing of potash to rice plant contributed to the increase of resistance to blast disease. However, there was no significant correlation between additional potassium application and the resistance to blast disease when the potassium content is already high in the leaf blades. 7. When four rice varieties were artificially inoculated with three strains of P. oryzae, the incidence of blast disease was most severe on Pungok, least severe on Jinheung and moderate on Pungkwang and Paltal varieties. 8. Disease incidence was most severe on the second leaf from top and less sever on top and there leaf regardless of the fertilizer application when 5-6 leaf stage rice seedlings of four rice varieties were artificially inoculated with three strains of P. oryzae. 9. The pathogenicity of three strains of P. oryzae was in the order of $P_1,\;P_2,\;and\;P_3$ in their virulence when inoculated to Jinheung, Paltal, Pungkwang varieties but not with Pungok. The interaction between strains of P. oryzae and rice varieties was significant.

• Tuberculosis and Respiratory Diseases
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• v.42 no.5
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• pp.669-676
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• 1995

Background: The cell-mediated immunity is needed for eradicating the tubercle bacilli. Prostaglandin(PG), especially PG $E_2$, is involved in cellular immunosuppression. It is known that the PG $E_2$ is suppressed by indomethacin. For using indomethacin as a immunomodulator of intractable pulmonary tuberculosis(Tbc) patients, we measured the tuberculin skin test(TST) and the plasma PG $E_2$ levels. Method: The forty-eight inpatients with sputum positive acid-fast stain bacilli were classified into 6 groups according to antiTbc chemotherapy history(new and intractable cases), plain chest roetgenogram(minimal and far advanced cases), and TST reaction(nagative and positive cases). Except for one group(n=2; new, minimal, and negative cases of TST reaction) of the 6 groups, all subjects(n=46) were measured for the plasma PG $E_2$, levels with radioimmunoassay. Results: 1) There was no significant difference in the plasma PG $E_2$ levels among A group(far advanced and positive TST reaction cases, n=10, $11.22{\pm}2.86\;pg/ml$), B group(minimal and negative TST reaction cases, n=9, $11.35{\pm}2.20$) and C group(far advanced and positive TST reaction cases, n=7, $11.11{\pm}2.30$) in the new cases(p>0.05). 2) There was no significant difference in the plasma PG $E_2$ levels between positive(n=10, $9.25{\pm}2.21$) and negative(n=10, $8.25{\pm}1.13$) groups by TST in the intractable cases(p>0.05). 3) Comparing the plasma PG $E_2$ levels between new(n=26, $11.35{\pm}2.41$) and intractable(n=20, $8.75{\pm}1.78$) groups, the intractable group had significi- andy lower plasma PG $E_2$ levels(p<0.05). 4) There was no significant difference in the plasma PG $E_2$ levels between negative(n=19, $9.88{\pm}2.43$) and positive(n=27, $10.46{\pm}2.56$) groups by TST(p>0.05). 5) There was no significant difference in the plasma PG $E_2$ levels between male(n=32, $10.07{\pm}2.44$) and female(n=14, $10.56{\pm}2.70$)(p>0.05). 6) There was no significant difference in the plasma PG $E_2$ levels among 2nd(n=5, $10.21{\pm}2.86$), 3rd(n=9, $9.97{\pm}2.47$), 4th(n=13, $11.35{\pm}2.33$) and 5th(n=19, $9.57{\pm}2.48$) decades(p>0.05). 7) There was no significant correlation between the induration sizes of the TST and the plasma PG $E_2$ levels(r=0.054, p>0.05). Conclusion: From the above results, the plasma PG $E_2$ levels of intractable group are not higher as the authors had expected. There was no significant difference in the plasma PG $E_2$ levels by the lesion sizes of plain chest roentgenogram and the induration sizes of TST, so more study will be needed to use the indomethacin as a immunomodulator for intractable pulmonary tuberculosis patients.

• Journal of Intelligence and Information Systems
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• v.20 no.3
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• pp.109-131
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• 2014

As the demand of nuclear power plant equipment is continuously growing worldwide, the importance of handling nuclear strategic materials is also increasing. While the number of cases submitted for the exports of nuclear-power commodity and technology is dramatically increasing, preadjudication (or prescreening to be simple) of strategic materials has been done so far by experts of a long-time experience and extensive field knowledge. However, there is severe shortage of experts in this domain, not to mention that it takes a long time to develop an expert. Because human experts must manually evaluate all the documents submitted for export permission, the current practice of nuclear material export is neither time-efficient nor cost-effective. Toward alleviating the problem of relying on costly human experts only, our research proposes a new system designed to help field experts make their decisions more effectively and efficiently. The proposed system is built upon case-based reasoning, which in essence extracts key features from the existing cases, compares the features with the features of a new case, and derives a solution for the new case by referencing similar cases and their solutions. Our research proposes a framework of case-based reasoning system, designs a case-based reasoning system for the control of nuclear material exports, and evaluates the performance of alternative keyword extraction methods (full automatic, full manual, and semi-automatic). A keyword extraction method is an essential component of the case-based reasoning system as it is used to extract key features of the cases. The full automatic method was conducted using TF-IDF, which is a widely used de facto standard method for representative keyword extraction in text mining. TF (Term Frequency) is based on the frequency count of the term within a document, showing how important the term is within a document while IDF (Inverted Document Frequency) is based on the infrequency of the term within a document set, showing how uniquely the term represents the document. The results show that the semi-automatic approach, which is based on the collaboration of machine and human, is the most effective solution regardless of whether the human is a field expert or a student who majors in nuclear engineering. Moreover, we propose a new approach of computing nuclear document similarity along with a new framework of document analysis. The proposed algorithm of nuclear document similarity considers both document-to-document similarity (${\alpha}$) and document-to-nuclear system similarity (${\beta}$), in order to derive the final score (${\gamma}$) for the decision of whether the presented case is of strategic material or not. The final score (${\gamma}$) represents a document similarity between the past cases and the new case. The score is induced by not only exploiting conventional TF-IDF, but utilizing a nuclear system similarity score, which takes the context of nuclear system domain into account. Finally, the system retrieves top-3 documents stored in the case base that are considered as the most similar cases with regard to the new case, and provides them with the degree of credibility. With this final score and the credibility score, it becomes easier for a user to see which documents in the case base are more worthy of looking up so that the user can make a proper decision with relatively lower cost. The evaluation of the system has been conducted by developing a prototype and testing with field data. The system workflows and outcomes have been verified by the field experts. This research is expected to contribute the growth of knowledge service industry by proposing a new system that can effectively reduce the burden of relying on costly human experts for the export control of nuclear materials and that can be considered as a meaningful example of knowledge service application.

• Economic and Environmental Geology
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• v.25 no.4
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• pp.417-433
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• 1992

Lead-zinc-copper deposits of the Jeonheung and the Oksan mines around Euiseong area occur as hydrothermal quartz and calcite veins that crosscut Cretaceous sedimentary rocks of the Gyeongsang Basin. The mineralization occurred in three distinct stages (I, II, and III): (I) quartz-sulfides-sulfosalts-hematite mineralization stage; (II) barren quartz-fluorite stage; and (III) barren calcite stage. Stage I ore minerals comprise pyrite, chalcopyrite, sphalerite, galena and Pb-Ag-Bi-Sb sulfosalts. Mineralogies of the two mines are different, and arsenopyrite, pyrrhotite, tetrahedrite and iron-rich (up to 21 mole % FeS) sphalerite are restricted to the Oksan mine. A K-Ar radiometric dating for sericite indicates that the Pb-Zn-Cu deposits of the Euiseong area were formed during late Cretaceous age ($62.3{\pm}2.8Ma$), likely associated with a subvolcanic activity related to the volcanic complex in the nearby Geumseongsan Caldera and the ubiquitous felsite dykes. Stage I mineralization occurred at temperatures between > $380^{\circ}C$ and $240^{\circ}C$ from fluids with salinities between 6.3 and 0.7 equiv. wt. % NaCl. The chalcopyrite deposition occurred mostly at higher temperatures of > $300^{\circ}C$. Fluid inclusion data indicate that the Pb-Zn-Cu ore mineralization resulted from a complex history of boiling, cooling and dilution of ore fluids. The mineralization at Jeonheung resulted mainly from cooling and dilution by an influx of cooler meteoric waters, whereas the mineralization at Oksan was largely due to fluid boiling. Evidence of fluid boiling suggests that pressures decreased from about 210 bars to 80 bars. This corresponds to a depth of about 900 m in a hydrothermal system that changed from lithostatic (closed) toward hydrostatic (open) conditions. Sulfur isotope compositions of sulfide minerals (${\delta}^{34}S=2.9{\sim}9.6$ per mil) indicate that the ${\delta}^{34}S_{{\Sigma}S}$ value of ore fluids was ${\approx}8.6$ per mil. This ${\delta}^{34}S_{{\Sigma}S}$ value is likely consistent with an igneous sulfur mixed with sulfates (?) in surrounding sedimentary rocks. Measured and calculated hydrogen and oxygen isotope values of ore-forming fluids suggest meteoric water dominance, approaching unexchanged meteoric water values. Equilibrium thermodynamic interpretation indicates that the temperature versus $fs_2$ variation of stage I ore fluids differed between the two mines as follows: the $fs_2$ of ore fluids at Jeonheung changed with decreasing temperature constantly near the pyrite-hematite-magnetite sulfidation curve, whereas those at Oksan changed from the pyrite-pyrrhotite sulfidation state towards the pyrite-hematite-magnetite state. The shift in minerals precipitated during stage I also reflects a concomitant $fo_2$ increase, probably due to mixing of ore fluids with cooler, more oxidizing meteoric waters. Thermodynamic consideration of copper solubility suggests that the ore-forming fluids cooled through boiling at Oksan and mixing with less-evolved meteoric waters at Jeonheung, and that this cooling was the main cause of copper deposition through destabilization of copper chloride complexes.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.3
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• pp.205-211
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• 2000

This study was conducted to evaluate the residual effects of basic oxygen furnace (BOF) slag applied in rice paddy fields as soil conditioner one year before. The experimental fields of Lim et al. (2000) located in Youjung and Nampyung were used for this purpose. Both variety (Oryza sativa L. cv. Dongjinbyeo) and cultural practices were the same as those in Lim et al. (2000). Soil chemical properties, plant height, number of tillers per plant, yield and yield components were observed. The temporal variation of treatment mean value in soil chemical properties appeared to be similar trends in both Youjung and Nampyung experimental fields. Soil pH and Ca content were still significantly higher than those in control treatment up to July of the second season, but decreased progressively as time passed. However, the effects lasted longer as slag rate became higher. BOF slag seems to have residual effects as a soil conditioner or Ca fertilizer in soil for two years. BOF slag rate of $4Mg\;ha^{-1}$ raised soil pH almost the same as lime rate of $2Mg\;ha^{-1}$. Content of $SiO_2$ in soil applied slag appeared to be higher compared with control. Fe and Mg content in soil with slag treatment was significantly higher than that of control in 1997, but it was almost the same level as that of control in 1998. In YouJung experimental field, rough rice yield of slag teatment became higher as slage rate incresed. Slag rate of $12Mg\;ha^{-1}$ showed the highest rough rice yield of $5,400kg\;ha^{-1}$ among treatment, which was 14% higher than that of control with $4,720kg\;ha^{-1}$. Slag rate of $12Mg\;ha^{-1}$ showed relatively higher plant height and higher number of tillers at the early growth stage compared with other treatments. In NamPyung experimental field, rough rice yield was the highest at the plot of lime rate $2Mg\;ha^{-1}$ and became higher as slag rate increased. There were no significant differences in rough rice yield between lime treatment and slag treatments. Slag rate of $12Mg\;ha^{-1}$ showed the highest rough rice yield of $7,170kg\;ha^{-1}$ among slag treatment, which was 8% significantly higher than that of control with $6,670kg\;ha^{-1}$. Slag rate of $12Mg\;ha^{-1}$ showed relatively slower growth in plant height at the early growth stage, but superior growth at the later growth stage, and significantly higher number of spiklets per panicle and 1000-grain weight than that of control.

• Korean Journal of Heritage: History & Science
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• v.46 no.1
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• pp.160-175
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• 2013

There is the need to make a sharp distinction as regards JANGSEUNGs (Korean traditional totem poles) that are different in origin, history and function. This study is to identify the functions of the figures, as well as to trace stone JANGSEUNGs to their origins. In this regard, researched were conducted into the origins of JANGSEUNGs and their changes in history. There was a tradition in the GORYEO Dynasty (an ancient dynasty in the Korean Peninsula) that it erected JANGSAENGs (the archaic name of JANGSEUNGs) or allied stone figures within temples; especially, 'TONGDOSA GUKJANGSAENG SEOKPYO (a stone JANGSAENG that was erected by the royal command and is at the entrance of TONGDO Temple located in YANGSAN, South GYEONGSANG Province, South Korea)' functions as a stone monument rather than as a stone sign. In the engraved inscription, it is written that it should be erected in the form of PANA as before. 'PANA' refers to 'ZHONGKUI', a god in Chinese Taoism believed to exorcise devils that spread diseases. The inscription is to define the territory of TONGDO Temple. The article on HAN JUN GYEOM in a book 'WORAKGI (a travelogue on WORAK Mountain in North CHUNGCHEONG Province, South Korea)' written by HEO MOK makes it possible to guess the scale of GUKJANGSAENGs erected in DOGAP Temple. The stones, on which 'GUKJANGSAENG' or 'HWANGJANGSAENG' were engraved, are not JANGSAENGs but are demarcation posts. In the JOSEON Dynasty (the last dynasty in the Korean Peninsula) JANGSAENGs functioned as signposts. Unlike JANGSAENGs in temples, they were made of wood. At first, the word 'JANGSAENG' was written '長生' in Chinese characters, but in the JOSEON Dynasty another character '木 (wood)' was added to them, and thus the orthography was likely to change into 'JANGSEUNG.' In the JOSEON Dynasty, in addition, optative or geomantic figures were not called 'JANGSEUNG.' Historically, for instance, there has been no case where 'DOL HARBANGs (stone figures found only in JEJU ISLAND, South Korea)' are called 'JANGSEUNG.' In a book 'TAMRA GINYEON (a historical record on JEJU Island, South Korea)' it is written that KIM MONG GYU, JEJU governor, erected ONGJUNG Stones outside the fortress gate. ONGJUNG Stones usually refer to stone statues erected in front of ancient kings or dignitaries' mausoleums. Moreover, they were geomantic figures erected to suppress miasma. A magazine 'GWANGJUEUPJI (a journal on old GWANGJU, South Korea, 1899)' shows that two two ONGJUNG Stones were so erected that they might look at each other to suppress miasma from a pathway through which lucks lose. On the two stone figures located in BUAN-EUP, North JEOLLA Province, South Korea, inscriptions 'SANGWON JUJANGGUN' and 'HAWON DANGJANGGUN' were engraved. The words are to identify the figures' sexes. They are a kind of optative geomantic figures, and therefore there is no reason to call them 'JANGSAENG' or 'JANGSEUNG' or 'DANGSAN.' The words 'SANGWON' and 'HAWON' are closely associated with Taoism. Since then, the words have been widely used as inscriptions on stone figures in temples, and subsequently are used for JANGSEUNGs. A hatted ONGJUNG Stone, found in BUKANSAN Fortress, disappeared and other ones may be being buried somewhere. Meanwhile, ONGJUNG Stones in JEJU Island and stone figures in BUAN-EUP have hardly been displaced and thus have properly functioned. Stone figures, made in those days, seem to be most similar in function to JANGSAENGs made during the GORYEO Dynasty. Specifically, like earlier JANGSAENGs, stone figures made during the early to mid-18th century were likely to function not only as optative figures but as boundary stones. Most of stone figures in temples were made whenever the land use survey was conducted throughout the nation, but given that at the same period of time, the commonalty filed many lawsuits against grave sites, temples might erect many stone figures to mark their territories. Currently, wooden or stone figures are commonly called 'JANGSEUNG', but they were erected in different epochs and for different reasons. Their origins are to be sought in stone figures that functioned not only as optative figures in temples but as boundary stones during the GORYEO Dynasty.

• Journal of the Mineralogical Society of Korea
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• v.32 no.2
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• pp.127-143
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• 2019

The geology of the Chulmasan area consists of Precambrain Sogeunri formation, granitic gneiss, foliated biotite granite, foliated mica granite, basic dyke and acidic dyke. REE mineralization in the area occurs at granitic gneiss and foliated mica granite. Minerals with minor amounts of REE and Th from granitic gneiss and foliated mica granite are zircon ($Y_2O_3$ 0.00~1.18 wt.%, $Gd_2O_3$ 0.00~0.59 wt.%, $Er_2O_3$ 0.00~0.22 wt.%, $Yb_2O_3$ 0.00~0.34 wt.%, $Lu_2O_3$ 0.00~0.48 wt.%, $ThO_2$ 0.00~0.33 wt.%), thorianite ($Nd_2O_3$ 0.00~0.24 wt.%, $Lu_2O_3$ 0.00~0.26 wt.%), berthierine ($La_2O_3$ 0.04~0.26 wt.%, $Nd_2O_3$ 0.00~0.20 wt.%, $Tb_2O_3$ 0.04~0.12 wt.%, $Dy_2O_3$ 0.17~0.26 wt.%, $Er_2O_3$ 0.33~0.44 wt.%, $Lu_2O_3$ 0.00~0.19 wt.%, $ThO_2$ 0.61~0.93 wt.%), chlorite ($La_2O_3$ 0.44~0.68 wt.%, $Ce_2O_3$ 0.12~0.13 wt.%, $Nd_2O_3$ 0.31~0.44 wt.%, $Eu_2O_3$ 0.03~0.08 wt.%, $Dy_2O_3$ 0.09~0.21 wt.%, $Ho_2O_3$ 0.04~0.14 wt.%, $Er_2O_3$ 0.18~0.32 wt.%, $Lu_2O_3$ 0.07~0.21 wt.%, $ThO_2$ 0.00~0.97 wt.%), biotite ($Nd_2O_3$ 0.02~0.08 wt.%, $Gd_2O_3$ 0.07~0.08 wt.%, $Tb_2O_3$ 0.02~0.07 wt.%, $Dy_2O_3$ 0.35~0.43 wt.%, $Ho_2O_3$ 0.15~0.26 wt.%, $Er_2O_3$ 0.24~0.28 wt.%, $Yb_2O_3$ 0.06~0.18 wt.%, $ThO_2$ 0.00~0.12 wt.%), orthoclase ($Dy_2O_3$ 0.05~0.12 wt.%, $Ho_2O_3$ 0.05~0.06 wt.%, $Er_2O_3$ 0.28 wt.%, $Yb_2O_3$ 0.06~0.12 wt.%) and plagioclase ($Ho_2O_3$ 0.01~0.03 wt.%, $Er_2O_3$ 0.10~0.27 wt.%, $ThO_2$ 0.11~0.13 wt.%). REE minerals (bastnaesite and fergusonite) were sealed fractures in mainly fledspar, mica, zircon, apatite and ilmenite. Therefore, bastnaesite and fergusonite from the Chulmasan area were formed from redissolution/reconcentration of REE-and Th-bearing minerals from granitic gneiss and foliated mica granite at late stage by several igneous activies and metamorphism.

• Korean Journal of Heritage: History & Science
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• v.56 no.4
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• pp.230-246
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• 2023

The wooden fence(木柵), which began to appear in the Bronze Age and is presumed to be the oldest defense facility in human history, was used as a fortress for the purpose of further strengthening military defense functions until after the Japanese Invasion of Korea in 1592 in the Joseon Dynasty(壬辰倭亂). As it was established as the concept of a fortress or a fence installed outside a fence castle(城柵) or barracks fence(營柵), its importance as an essential facility for defense was further highlighted. This study is the result of exploring wooden fence that were used as official facilities during the Joseon Dynasty, focusing on literature surveys such as 『Annals of the Joseon Dynasty』 and 『New Jeungdonggukyeojiseungram』 In this study, in particular, the conclusion of this study is as follows, focusing on the use and function of Nokgakseong(鹿角城), underwater wooden fence, installation methods, and materials of wooden fences, is as follows. The conclusions of this study, which focused on the materials of the wooden fence, are as follows. First, as invasions by foreign enemies became more frequent in the late Goryeo and early Joseon Dynasty, wooden fences played a major role as a major out-of-castle defense facility((防禦施設). In addition, wooden fences were modified and installed into various types such as wooden fences(木柵城), Nokgakseong, a fence made up of large branches in the shape of a deer antler, and underwater wooden fences(水中木柵) according to the circumstances of the times, government policy, and location environment. Second, wooden fences were installed in strategic locations in defense facilities for military purposes, such as mountain fortress(山城), fortresses(營), camps(鎭), forts(堡), and castles(邑城) in strategic locations, and were used for defense in case of emergency. According to the urgency of farming, it was installed in accordance with the non-farming season, when it is easy to mobilize manpower to avoid the busy farming season. The size of the wooden fence of the Joseon Dynasty, which are confirmed through literature records, was converted into Pobaekchuk(布帛尺), and the circumference was very diverse from 4,428chuk(2,066m) to 55chuk(25m). Third, Nokgakseong is an efficient combat support facility that is more aggressive than a general wooden fence, and the records of Nokgakseong in the Annals of the Joseon Dynasty appeared during the King Sejong period the record was 20 times, the most. By region, it was found that it was mainly installed in coastal rugged areas such as Pyeongan and Hamgildo(12), which are the 6-jin areas of the 4th Army. Fourth, in the early 15th century, as the royal court established a maritime defense strategy for the coastal area of the southern coast, after the Sampo Invasion(三浦倭亂), riots by Japanese settlers in Sampo in 1510, major military posts including eupseong(邑城), camps, and forts were established. The installation of underwater barriers around various government facilities rapidly increased as a defense facility to block the warships of Japanese pirates around various government facilities. Fifth, between the 15th and 17th centuries before and after the Japanese Invasion of Korea in Sampo, underwater fences were installed in the Southern coast and Ganghwa Island. In particular, in the 15th century, underwater fences were intensively installed in coastal areas of Gyeongsangnam-do, such as Jepo. Pine trees and Oaks are the main materials used for underwater fences, but other materials such as Oldham's meliosma, Loose-flower hornbeam and The vines of arrowroots were also used as materials for wooden fences.

• Korean Journal of Agricultural Science
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• v.30 no.1
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• pp.31-40
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• 2003

A research has been done for growing characteristics of Korean ginseng in Geumsan of Chungnam Province. It had been made to determine the transitional element concentrations of the rocks, divided by biotitic granite(GR) and phyllite(PH). The physical and chemical properties of their weathering soils and ginseng nursery soils were analyzed. The texture in the GR weathering and ginseng nursery soils were sandy clay, and the texture of the PH weathering and ginseng nursery soils were heavy or silty clay. The bulk densities of the GR and PH weathering soils were $1.21{\sim}1.32g/cm^3$ and $1.26{\sim}1.38g/cm^3$, respectively. Also, the bulk densities of the GR and PH ginseng nursery soils were $1.02{\sim}1.10g/cm^3$, respectively. The pH (4.80) of the GR weathering soil were lower than the pH of the PH(5.34) weathering soil. The pH in the 2 year and 4 year-ginseng nursery soil of the GR were 4.39 and 4.40. In addition, those of the PH were 5.24 and 5.34, respectively. The difference in pH of the two nursery soils could be from the pH difference between the two parent materials. The organic matter contents of the GR weathering soils(0.24%) were higher than those of the PH(1.02%) weathering soils. The organic matter of the 2 and 4 year-ginseng GR nursery soils were 0.87% and 1.52%, and of the PH nursery soils were 2.06% and 2.96%, respectively. The total nitrogen contents of the GR weathering soils were 259.43ppm and of the PH weathering soils were 657.22ppm. Those of 2 and 4 year-ginseng GR nursery soils were 588.04ppm and 657.22ppm and those of the PH nursery soils were 1037.72ppm and 1227.96ppm, respectively. The nitrate and ammonium contents of the GR weathering soils were the extremely small, and those of the PH weathering soils were 6.7ppm and 9.94ppm. Those of 2 year-ginseng GR nursery soils(223.09ppm and 26.96ppm) were higher than those of PH(19.46ppm and 8.23ppm) nursery soils. And those of 2 year-ginseng PH nursery soils(14.22ppm and 16.84ppm) were lower than those of PH(306.93ppm, 34.21ppm) nursery soils. The difference was due to fertilizer types and more deposits of nitrate after oxidation of ammonium. The phosphate contents of the GR and PH weathering soils were 14.41ppm and 38.60ppm. Those of GR 2 and 4 year-ginseng nursery soils were 46.89ppm and 102.44ppm and those of the PH nursery soils were 147.04ppm and 38.60ppm. The cation exchange capacities of the GR weathering soils were 12.34me/100g and those of the PH weathering soils were 15.40me/100g. Those of 2 and 4 year-ginseng GR nursery soils were 15.80me/100g and 7.70me/100g and those of PH nursery soils were 12.14me/100g and 12.83me/100g. All of exchangeable cation($K^+$, $Ca^{2+}$, $Mg^{2+}$, $Na^+$) contents in the nursery soils were higher than those in the weathering soils. The $SO_4{^2-}$ contents of the weathering soils in both of the GR(5.98ppm) and PH(9.94ppm) were higher than those of the GR and PH ginseng nursery soils. The $Cl^-$) contents of the GR and PH weathering soils were a very small and those of the nursery soils(2-yr GR: 39.06ppm, 4-yr GR: 273.43ppm, 2-yr PH: 66.41ppm, 4-yr PH: 406.24ppm) were high because of fertilizer inputs.

• The Korean Journal of Petroleum Geology
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• v.8 no.1_2 s.9
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• pp.1-43
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• 2000

A comparison study for understanding a stratigraphic response to tectonic evolution of sedimentary basins in the Yellow Sea and adjacent areas was carried out by using an integrated stratigraphic technology. As an interim result, we propose a stratigraphic framework that allows temporal and spatial correlation of the sedimentary successions in the basins. This stratigraphic framework will use as a new stratigraphic paradigm for hydrocarbon exploration in the Yellow Sea and adjacent areas. Integrated stratigraphic analysis in conjunction with sequence-keyed biostratigraphy allows us to define nine stratigraphic units in the basins: Cambro-Ordovician, Carboniferous-Triassic, early to middle Jurassic, late Jurassic-early Cretaceous, late Cretaceous, Paleocene-Eocene, Oligocene, early Miocene, and middle Miocene-Pliocene. They are tectono-stratigraphic units that provide time-sliced information on basin-forming tectonics, sedimentation, and basin-modifying tectonics of sedimentary basins in the Yellow Sea and adjacent area. In the Paleozoic, the South Yellow Sea basin was initiated as a marginal sag basin in the northern margin of the South China Block. Siliciclastic and carbonate sediments were deposited in the basin, showing cyclic fashions due to relative sea-level fluctuations. During the Devonian, however, the basin was once uplifted and deformed due to the Caledonian Orogeny, which resulted in an unconformity between the Cambro-Ordovician and the Carboniferous-Triassic units. The second orogenic event, Indosinian Orogeny, occurred in the late Permian-late Triassic, when the North China block began to collide with the South China block. Collision of the North and South China blocks produced the Qinling-Dabie-Sulu-Imjin foldbelts and led to the uplift and deformation of the Paleozoic strata. Subsequent rapid subsidence of the foreland parallel to the foldbelts formed the Bohai and the West Korean Bay basins where infilled with the early to middle Jurassic molasse sediments. Also Piggyback basins locally developed along the thrust. The later intensive Yanshanian (first) Orogeny modified these foreland and Piggyback basins in the late Jurassic. The South Yellow Sea basin, however, was likely to be a continental interior sag basin during the early to middle Jurassic. The early to middle Jurassic unit in the South Yellow Sea basin is characterized by fluvial to lacustrine sandstone and shale with a thick basal quartz conglomerate that contains well-sorted and well-rounded gravels. Meanwhile, the Tan-Lu fault system underwent a sinistrai strike-slip wrench movement in the late Triassic and continued into the Jurassic and Cretaceous until the early Tertiary. In the late Jurassic, development of second- or third-order wrench faults along the Tan-Lu fault system probably initiated a series of small-scale strike-slip extensional basins. Continued sinistral movement of the Tan-Lu fault until the late Eocene caused a megashear in the South Yellow Sea basin, forming a large-scale pull-apart basin. However, the Bohai basin was uplifted and severely modified during this period. h pronounced Yanshanian Orogeny (second and third) was marked by the unconformity between the early Cretaceous and late Eocene in the Bohai basin. In the late Eocene, the Indian Plate began to collide with the Eurasian Plate, forming a megasuture zone. This orogenic event, namely the Himalayan Orogeny, was probably responsible for the change of motion of the Tan-Lu fault system from left-lateral to right-lateral. The right-lateral strike-slip movement of the Tan-Lu fault caused the tectonic inversion of the South Yellow Sea basin and the pull-apart opening of the Bohai basin. Thus, the Oligocene was the main period of sedimentation in the Bohai basin as well as severe tectonic modification of the South Yellow Sea basin. After the Oligocene, the Yellow Sea and Bohai basins have maintained thermal subsidence up to the present with short periods of marine transgressions extending into the land part of the present basins.