• Economic and Environmental Geology
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• v.40 no.2 s.183
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• pp.191-207
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• 2007

A paleomagnetic investigation for the Cretaceous rocks in the Buyeo and Hampyeong Basins, located out of the Gyeongsang Basin, was carried out in order to elucidate the paleomagnetic directions in conjunction with the formation of the basins. Typical stepwise thermal demagnetization and measurement methods were used to determine the directions of characteristic remanent magnetizations (ChRMs). The mean direction of the sedimentary rocks from the Buyeo Basin after bedding correction $(D/I=356.5^{\circ}/61.5^{\circ},\;k=39.3\;\alpha_{95}=7.4^{\circ})$, is more dispersed than that before bedding correction $(D/I=356.5^{\circ}/61.5^{\circ},\;k=39.3\;\alpha_{95}=7.4^{\circ})$, which suggests that the rocks in the Buyeo Basin were remagnetized. However, the statistics and dispersion of the ChRM directions after bedding correction are still acceptable and the paleomagnetic pole position after tilt correction $(Lat./Long.=69.3^{\circ}N/186.7^{\circ}E,\;K=11.6\;A_{95}=14.0^{\circ})$ is closer to that of the Late Cretaceous pole of the Korean Peninsula. More detailed study is needed to confirm the nature of the remagnetization in the Buyeo Basin. On the other hand, the paleomagnetic pole before bedding correction $(Lat./Long.=81.6^{\circ}N/106.9^{\circ}E,\;K=25.1\;A_{95}=9.3^{\circ})$ is positioned near the paleogene pole of the Eurasian APWP. The mean ChRM direction of the sedimentary rocks from the Hampyeong Basin after bedding correction is $D/I=32.5^{\circ}/55.4^{\circ},\;(k=35.6,\;\alpha_{95}=8.7^{\circ})$. It is more clustered than that before bedding correction $D/I=18.3^{\circ}/62.5^{\circ},\;k=14.1,\;\alpha_{95}=14.2^{\circ})$, indicating that the ChRM was acquired before tilting of the strata. The paleomagnetic pole position of the Cretaceous sedimentary rocks in the Hampyeong Basin, averaged out of site pole positions calculated from the tilt-corrected ChRMs, is $Lat./Long.=63.9^{\circ}N/202.7^{\circ}E,\;(K=21.3,\;A_{95}=7.6^{\circ})$, similar to the Late Cretaceous paleomagnetic pole of the Korean Peninsula $(Lat./Long.=70.9^{\circ}N/215.4^{\circ}E,\;A_{95}=5.3^{\circ})$, suggesting that the Hampyeong Basin has been stable since the Late Cretaceous period. One normal and two reversed ChRM directions are revealed through the measurements of the volcanic rocks from the Hampyeong Basin. Although these normal and reversed directions are not exactly antipodal, it is interpreted that the normal direction is the representative primary direction of the volcanic rocks of the Hampyeong Basin and the mixed polarity is the records of geomagnetic field at the time of the formation of the volcanic rocks. Paleomagnetic poles are at $Lat./Long.=70.2^{\circ}N/199.5^{\circ}E,\;(K=18.1,\;A_{95}=9.6^{\circ})$ for the normal direction, and $Lat./Long.=65.5^{\circ}S/251.3^{\circ}E,\;(K=7.1,\;A_{95}=20.7^{\circ})$ for the reversed direction. Compared with the representative pole positions of the Cretaceous period of the Korean Peninsula, it is concluded that the age of the volcanic rocks in the Hampyeong Basin is of the Late Cretaceous.

• Journal of the Korean earth science society
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• v.21 no.6
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• pp.683-694
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• 2000

Abstrace: The palaeodepositional environment and age of the Cretaceous Hampyeong Basin (southwestern Korea) are reassessed based on new geochemical, lithological, sedimentological, and palaeobotanical data. Results indicate that the Hampyeong Basin was a tectonically active basin comprising predominantly fluvial and lacustrine sediments. Four distinctive facies types have been identified (acidic tuff, black shales/sandstones, red beds, intermediate tuff with tuffaceous conglomerate) and these reflect periods of significant environmental change within the basin and its neighbouring terrains. Volcanism driven by tectonic events provides a source for much of the sediment. The sedimentary sequences compare well with those in the neighbouring Haenam Basin. Sediments of volcanic origin are similar to those of the Neungju Formation of the Yuchon Group. The widespread occurrence of black shales is indicative of extended periods of deposition under anoxic conditions. Measurements of total organic carbon show that the values for the black shales (0.81% to 1.75%) are the average for petroleum source shales. Fossil plants occurred in the black shales and sandstones. The occurrence of platanoid leaves places these sediments in Oishi's angiosperm series, which is consistent with an Aptian/Albian or younger age.

• Economic and Environmental Geology
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• v.46 no.6
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• pp.545-559
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• 2013

Until now, research achievements of groundwater such as groundwater to depth distribution, usage, the available amount of development, water quality have been written in the watershed units($25{\sim}250km^2$). However, complex topography and geology, and the rivers of our country does not fit. And a clear management standards have not been able to present measures in groundwater quantity, water quality management such as rainfall, groundwater, utilization, water quality, pollution, etc. Therefore, in this study, the classification criterion of subwatershed unit($2.5{\sim}25km^2$), which is suitable for topography and geology of Korea, for rainfall-rating, groundwater level-rating, groundwater pollution-rating, groundwater quality-rating presented and proved its efficiency by applying in Hampyeong-Gun area.

• Journal of Conservation Science
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• v.18 s.18
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• pp.33-50
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• 2006

Around Yeongsan river basin, there are Yeongkwang Gundong, Muan Inpyeong Tombs, Muu Gusan-ri Tombs and Hampyeong Guksan remain from which a lot of iron artifacts were excavated. Among them, 6 iron artifacts were chosen, and their microstructures were analyzed. As a result, Iron artifacts were produced sponge iron by the low temperature reduction process and a part of microstructure have the possibility that steel made by decarburizing. And also, by tempering the parts which need high strength, the iron artifacts had high strength and by distributing the weakness of the tempered structure to the nearby untempered parts, their breaking was prevented and they had the durability. These skills were used then. Especially these skills were found to be used in the 2nd century by high skilled people because an iron axe excavated at Yeongkwang Gundong of 2nd century by the historical record showed that the skill was used. Also microstructures were found to show the possibility that the iron technology was inherited to the late 5th century. When producing iron artifacts made of sponge iron containing small amount of carbon, that was made by the production process repeating molding, carburizing, heat treatment and hammering.

• The Journal of the Petrological Society of Korea
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• v.26 no.3
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• pp.201-219
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• 2017

The Jinan Basin which includes Maisan locates in the central part of the northern boundary of the Yeongnam Massif. The basement rocks of the Jinan Basin and surrounding area are Precambrian gneiss and Mesozoic granite which were exposed on the surface before Cretaceous. The Jinan Basin, one of the Cretaceous pull-apart basins in South Korea, formed along the Yongdong-Gwangju fault system. Maisan is composed of conglomerate deposited in the eastern slope of the Jinan Basin showing the shape of horse ears and the unusual topography where many tafonies were developed. The strike slip fault that caused the Jinan Basin was connected to the deep depth so that the magma formed at 200 km depth could have extruded on the surface causing active volcanic activity in and around the Jinan basin. As a result, Cheonbansan composed of pyroclastic rocks, Gubongsan consisting of volcanic neck and WoonilamBanilam formed by the lava flow, appear around Maisan forming a specific terrain. After the formation of the Jinan Basin and surrounding volcanic rocks, they uplifted to form mountains including Masian; the uplifting time may be ca. 69-38 Ma. At this time, the Noryeong mountain range may be formed in the regions which extended from Chugaryeong through Muju and Jinan to Hampyeong dividing the Geumgang and Seomjingang water systems. Due to the ecological barrier, the Noryeong mountain range, Coreoleuciscus splendidus living in the Geumgang water systems was differentiated from that in the Soemjingang water system. In addition, the Geumgang and Mangyeong-Dongjingang water systems were separated by the Unjangsan, which developed in the NNW direction. As a result, diverse ecosystem have been established in and around Maisan and at the same time, diverse cultural and historical resources related to Maisan's unique petrological features, were also established. Therefore, Maisan and surrounding area can be regarded as a place where a geotourism can be successfully established by combining the ecological, cultural and historical resources with a geological heritage. Therefore Maisan and surrounding areas have a high possibility to be a National Geopark and UNESCO Global Geopark.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.6
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• pp.763-774
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• 2023

The water availability in a river is related to the return flow of residential water. However it is still difficult to determine the exact return flow. In this study, the residential water-cycle system is defined as a process consisting of water inflow, water transfer and water outflow. The study area is Hampyeong-gun, Jeollanam-do, and is set as a single inflow to a single outflow through the water-cycle system after classification of complete and incomplete measurement points. The time-series prediction models(ARIMA model and TFM) are established with daily inflow and outflow data for 6 years. Inflow and outflow are predicted by dividing into training and test periods. As a result, both models show the feasibility of short-term prediction by deriving stable residuals and securing statistical significance, implementing the preliminary form of the water-cycle system. As a further study, it is suggested to predict the actual return flow of the target basin and efficient water operation by adding input factors and selecting the optimal model.

• Economic and Environmental Geology
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• v.41 no.3
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• pp.275-286
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• 2008

The Sambo gold deposit located nearby the Cretaceous Hampyeong basin is composed of gold quartz fine vein(the Jija vein) within Cretaceous rhyolite showing $N10{\sim}20W$ trends as well as $N5{\sim}10E$ trending quartz veins(the Pungja, Gwangsan and Pungjaji veins) in Precambrian gneiss. The gold vein typically displays the intermittent and irregular fine veins within rhyolite. Electrum is disseminated in wallrock along the fine cracks as well as coexists with hematite replacing pyrite. Ore-forming fluids from the mineralized vein($H_2O/-NaCl$ system, Th; $340{\sim}200^{\circ}C$, Salinity <2.7 eq. wt.% NaCl) and NE-trending veins($H_2O-NaCl/-CO_2$ system, Th; $400{\sim}190^{\circ}C$, salinity <7.9 eq. wt.% NaCl) are featured by dissimilar physicochemical conditions but their fluid evolution trends(boiling and mixing) are similar with each other. Gold veins of the Sambo deposit filled along NNW-trending tension crack are related to pull-apart basin evolution. Selective gold mineralization of the deposit reflect to dissimilarity between two ore-forming fluid sources. Consequently, gold veining of the Sambo deposit formed at shallow-crustal level and could be categorized into epithermal-type gold deposit related to tensional fractures filling triggered by Cretaceous geodynamics.