한국 서해 경기만 조간대 퇴적층의 퇴적물 특성과 층서

조주환,김영성,임동일 조선대학교 사범대학 부설 교과교육연구소 2001 敎科敎育硏究 Vol.4 No.1

경기만 반월 조간대 퇴적분지의 퇴적 층서를 밝히기 위해 2지점에서 평균 20m에 달하는 심부시추를 실시하였다. 시추된 퇴적물은 퇴적환경과 경계면의 특성에 의해 크게 2개의 퇴적단위 UnitⅠ과 UnitⅡ로 구분된다. UnitⅠ은 5-10m의 두꺼운 니질 퇴적물로 구성되며, 현세 해침기간동안 점이적인 해수면 상승과 힘께 형성된 현세 니질 조간대 퇴적층으로 해석된다. 기반암을 부정합적으로 피복하고 있는 퇴적단위 UnitⅡ는 두께가 최대 10m에 달하며, 조립의 자갈과 모래로 구성된다. 조립의 사질 퇴적물은 동해의 사구에 비하여 원마도가 낮고, 서해의 대륙붕 퇴적물보다는 높은 원마도를 나타낸다. 이러한 결과들은 UnitⅡ 퇴적물이 다소 강한 유수 작용에 의한 하천 퇴적물임을 제시한다. 결론적으로 생물 파편의 부재, 역사질의 조립한 퇴적물 조직, 쇄설성 입자의 형태 특성 그리고 층서 위치 등을 고려할 때 퇴적단위 UnitⅡ는 현세 해침이전 최대빙하기(LGM)동안 퇴적된 육성의 하천 퇴적물로 해석된다. To elucidate the stratigraphy of Banweol tital-flat deposits, Kyunggi Bay, western coast of Korea, two boreholes, up to 20 m in thickness, were taken using a well-unilized deep-drilling equipment. On the basis of depositional enviornment and erosional boundary, these deepdrilled borehole sediments can be divided into two sedimentary units(UnitⅠ and UnitⅡ). UnitⅠ reaches up to 10 m in thickness and consists mainly of mud and silt sediments with mean grain size of 7-9 phi. This unit is interpreted as a typical intertidal-flat deposition accumulated during mid-to-late Holocence sea-level rise. Beneath the Holocence tidal-flat mud(UnitⅠ) are very coarse-grained sandy sediments (UnitⅡ) woth approximately 10 m thick. Roundness in UnitⅡ sediments is lower than those of relict shelf sediments. Considering the texture, grain shape, stratigraphic position, and absence of biogenic materials, UnitⅡ might be accumulated under the active hydrodynamic condition of the fluvial enviornment during sea-level lowstand, possibly last glacial maximum(LGM).

The Occurrence of Glauconite Grains on the Continental Shelves off the Korean Peninsula: Distribution, Morphology and Origin

Lim, Dhong-Il,Park, Yong-Ahn,Cho, Ju-Whan,Choi, Jin-Yong The Korean Society of Oceanography 1999 Journal of the Korean Society of Oceanography Vol.34 No.2

Glauconite grains are widely distributed in the outer shelf surficial sandy sediments of the Korean continental shelves. Morphologically, these grains are characterized by ovoidal-shaped pellets with bulbous exterior, greenish color and moderately well polished surface. In thin sections, the glauconite grains are massive and contain numerous impurities composed mainly of quartz, feldspar and mica. The morphologies and microscopic examinations indicate mainly fecal pellet as a parent matierials for glauconite. SEM examination shows that glauconitic smectite crystals grow in pores and along fractures of the host grains, commonly as a boxwork arrangement or rosette clusters of blades. Bulbous external shape, high potassium content and rosette-shaped smectite structure, reflect the evolved stage (more than 10$^4$ years in age) of glauconite authigenesis. Moreover, the association of the glauconite grains with the relict sandy sediments on the outer shelf, impliesthat the glauconite grains are geologically old, or at least have formed under the environmental conditions different from the present shelf. The widespread occurrence of the glauconite grains, therefore, might be primarily related with redeposition of sediments transported from the outer shelf during Holocene transgression.

Transgressive Geochemical Records in the East China Sea: A Perspective with Holocene Paleoceanography

Sangmin Hyun,Dhong-il Lim,Hai-Soo Yoo 대한자원환경지질학회 2006 자원환경지질 Vol.39 No.1

Geochemical and sedimentological analyses of sediment piston core were used to trace paleoceanographic environmental changes in the East China Sea. The analytical results revealed three lithostratigraphic units (I, II, and III) corresponding to a highstand stage, a transgressive stage, and a lowstand stage, respectively. Accelerator mass spectrometry(AMS) 14C dated the boundaries between the units as 7 ka and 11 ka. That is, Unit I extended from the present to 7 ka, Unit II occupied a transitional episode from 7 to 11 ka, and Unit III was older than 11 ka. The transitional episode was characterized by sudden fluctuations in various geochemical proxies. Most strikingly, there was a gradual upward increase in both carbonate and total organic carbon (TOC) contents post-7 ka, during which time the δ13C values of organic material increased to a constant value. The gradual upward increase in the TOC and CaCO3 contents in Unit I were accompanied by slight variations in grain size that probably reflect a stable modern oceanographic environment. Within Unit II (7 to 11 ka), the geochemical signals were characterized by abrupt and steep fluctuations, typical of a transgressive stage. Vertical mixing may have provoked an increase in productivity during this interval, with large amounts of terrigenous organic matter and/or freshwater being supplied by neighboring rivers. The geochemical signals remained stable throughout Unit III but exhibited different patterns than signals in Unit I. The high terrigenous organic matter content of Unit III suggests correspondence to a lowstand stage.

Transgressive Geochemical Records in the East China Sea: A Perspective with Holocene Paleoceanography

Hyun Sangmin,Lim Dhong-il,Yoo Hai-Soo The Korean Society of Economic and Environmental G 2006 자원환경지질 Vol.39 No.1

Geochemical and sedimentological analyses of sediment piston core were used to trace paleoceanographic environmental changes in the East China Sea. The analytical results revealed three lithostratigraphic units (I, II, and III) corresponding to a highstand stage, a transgressive stage, and a lowstand stage, respectively. Accelerator mass spectrometry (AMS) $^{14}C$ dated the boundaries between the units as 7 ka and II ka. That is, Unit I extended from the present to 7 ka, Unit II occupied a transitional episode from 7 to 11 ka, and Unit III was older than 11 ka. The transitional episode was characterized by sudden fluctuations in various geochemical proxies. Most strikingly, there was a gradual upward increase in both carbonate and total organic carbon (TOe) contents post-7 ka, during which time the ${\delta}^{l3}C$ values of organic material increased to a constant value. The gradual upward increase in the TOC and $CaCO_3$ contents in Unit I were accompanied by slight variations in grain size that probably reflect a stable modern oceanographic environment. Within Unit II (7 to 11 ka), the geochemical signals were characterized by abrupt and steep fluctuations, typical of a transgressive stage. Vertical mixing may have provoked an increase in productivity during this interval, with large amounts of terrigenous organic matter and/or freshwater being supplied by neighboring rivers. The geochemical signals remained stable throughout Unit III but exhibited different patterns than signals in Unit I. The high terrigenous organic matter content of Unit III suggests correspondence to a lowstand stage.

Widespread Anthropogenic Nitrogen in Northwestern Pacific Ocean Sediment

Kim, Haryun,Lee, Kitack,Lim, Dhong-Il,Nam, Seung-Il,Kim, Tae-Wook,Yang, Jin-Yu T.,Ko, Young Ho,Shin, Kyung-Hoon,Lee, Eunil American Chemical Society 2017 Environmental science & technology Vol.51 No.11

<P>Sediment samples from the East China and Yellow seas collected adjacent to continental China were found to have lower delta N-15 values (expressed as delta N-15 = [N-15:N-14(sample)/N-15:N-14(air) - 1] x 1000; the sediment N-15:N-14 ratio relative to the air nitrogen 15N:14N ratio). In contrast, the Arctic sediments from the Chukchi Sea, the sampling region furthest from China, showed higher delta N-15 values (2-3 higher than those representing the East China and the Yellow sea sediments). Across the sites sampled, the levels of sediment delta N-15 increased with increasing distance from China, which is broadly consistent with the decreasing influence of anthropogenic nitrogen (N-ANTH) resulting from fossil fuel combustion and fertilizer use. We concluded that, of several processes, the input of N-ANTH appears to be emerging as a new driver of change in the sediment delta N-15 value in marginal seas adjacent to China. The present results indicate that the effect of N-ANTH has extended beyond the ocean water column into the deep sedimentary environment, presumably via biological assimilation of N-ANTH followed by deposition. Further, the findings indicate that N-ANTH is taking over from the conventional paradigm of nitrate flux from nitrate-rich deep water as the primary driver of biological export production in this region of the Pacific Ocean.</P>

Increase in anthropogenic mercury in marginal sea sediments of the Northwest Pacific Ocean

Kim, Haryun,Lee, Kitack,Lim, Dhong-Il,Nam, Seung-Il,Han, Seung hee,Kim, Jihun,Lee, Eunil,Han, In-Seong,Jin, Young Keun,Zhang, Yanxu Elsevier 2019 Science of the Total Environment Vol.654 No.-

<P><B>Abstract</B></P> <P>Over the past century, the addition of anthropogenic mercury (Hg<SUP>ANTH</SUP>) to vast areas of North Pacific marginal seas adjacent to the northeast Asian continent has tripled. Analysis of sediment cores showed that the rate of Hg<SUP>ANTH</SUP> addition (Hg<SUP>ANTH</SUP> flux) was greatest in the East China and Yellow Seas (9.1 μg m<SUP>−2</SUP> yr<SUP>−1</SUP>) in the vicinity of China (the source continent), but was small in the Bering and western Arctic Ocean (Chukchi Sea) (0.9 μg m<SUP>−2</SUP> yr<SUP>−1</SUP>; the regions furthest from China). Our results show that Hg<SUP>ANTH</SUP> has reached open ocean sedimentary environments over extended areas of the northwestern Pacific Ocean, via the formation of organic-mercury complexes and deposition. The implication of these findings is that the addition of Hg<SUP>ANTH</SUP> (via atmospheric deposition and riverine input) to the ocean environment is responsible for elevated Hg flux into sedimentary environments in the northwest Pacific Ocean.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The flux of Hg<SUP>ANTH</SUP> into sediments increased from the western Arctic Ocean to the East China Sea. </LI> <LI> The highest rate of Hg<SUP>ANTH</SUP> flux into sediments was found in the East China Sea. </LI> <LI> Hg<SUP>ANTH</SUP> has reached open ocean sediments over extended areas of the northwestern Pacific Ocean. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

한국 서남해 함평만 조간대 퇴적층의 제4기 후기 층서 연구

박용안,임동일,최진용,이영길,Park, Yong-Ahn,Lim, Dhong-Il,Choi, Jin-Yong,Lee, Young-Gil 한국해양학회 1997 바다 Vol.2 No.2

한반도 서남 해역에 위치한 함평만(전라남도 함평군) 조간대 퇴적층의 제 4기 후기 층서와 퇴적학적 연구를 위하여 총 37 지점에서 평균 3 m 깊이(최대 5.2 m)의 시추가 실시되었다. 채취된 퇴적물 시료의 입자 조직(grain texture), 퇴적 구조(sedimentary structure), 색(color) 및 광물 조성(mineral composition) 등을 토대로 10개의 퇴적상(sedimentary facies)이 분류되었다. 분석 결과에 의하면, 함평만 조간대 퇴적분지의 층서는 상위로부터 순차적으로 층서단위 Unit I, Unit II 및 Unit III로 구성된다. 최상위의 층서단위 Unit I은 조립질 퇴적상인 비조직 사질역 퇴적상(Facies SGd)과 괴상 역질 이토 퇴적상(Facies GMm) 또는 세립질 퇴적상인 엽층리 실트 퇴적상(Facies Zp), 괴상 이토 퇴적상(Facies Mm) 및 평행 엽층리 이토 퇴적상(Facies Mp)으로 구성되며, 상향 조립화의 특정을 나타낸다. 이 퇴적층은 해수면이 거의 현재의 위치에 도달된 지난 약 4.000년 동안 형성된 후기 현세(late Holocene) 해침 퇴적층으로 해석된다. Unit I에 의하여 부정합적으로 피복되는 층서단위 Unit II는 준 고화된 황색 이토 퇴적상 (Facies Mym)과 회색의 미고결된 니질 퇴적상(Facies Mgm)으로 구성되며, 수평적 연속성이 양호하고, 함평만 전체에 광역적으로 분포한다. Unit II는 서해의 여러 조간대에서 보고된 간월도층과 대비되는 것으로 여겨지며, 후기 플라이스토세(late Pleistocene)의 조간대 퇴적환경에서 집적된 퇴적층으로 해석된다. 이러한 Unit II에는 지난 최대 빙하기 동안 대기중에 노출된 다양한 증거(황갈색, 고화상태, 동토구조, 점토광물의 함량 변화등) 들을 함유한다. Unit II에 의하여 부정합적으로 피복되는 Unit III는 역질의 층리를 갖는 조립의 퇴적물(Facies SGb와 Facies Sx)로 구성되며 내만역의 한정된 지역(후동과 시목동 해역)에 분포한다. 퇴적학적 특성과 지역적인 분포 양상을 고려할 때, Unit III는 육성 환경(nonmarine deposits)의 하천 퇴적물(fluvial sediment)로 해석된다. 결과적으로 함평만 조간대 퇴적분지의 층서(최고기로부터 최신기)는 기반암 지층(중생대 화강암)${\rightarrow}$육성 퇴적층(Unit III)${\rightarrow}$후기 플라이스토세의 니질 조간대 퇴적층(Unit II)${\rightarrow}$후기 현세의 조간대 퇴적층(Unit I)의 층서이며, 각각의 층서단위의 경계는 부정합적이다. The late Quaternary stratigraphy of the tidal deposits in the Hampyung Bay, southwestern coast of Korea comprises 1) Unit III (nonmarine fluvial coarse-grained sediments), 2) Unit II (late Pleistocene tidal deposits), and 3) Unit I (late Holocene fine-grained tidal deposits) in ascending order. The basements of the Hampyung Bay is composed of granitic rocks and basic dyke rocks. These three units are of unconformally bounded sedimentary sequences. The sequence boundary between Unit I and Unit II, in particular, seems to be significant suggesting erosional surface and exposed to the air under the cold climate during the LGM. The uppermost stratigraphic sequence (Unit I) is a common tidal deposit formed under the transgression to highstand sea-level during the middle to late Holocene.

북동중국해 코아 퇴적물의 희토류원소 분포양상과 기원

정회수,임동일,유해수,Jung Hoi-Soo,Lim Dhong-il,Yang Shou Ye,Yoo Hai-Soo 대한자원환경지질학회 2006 자원환경지질 Vol.39 No.1

Rare earth elements(REEs) in transgressive shelf core sediments were analysed to identify constraints of REE distribution patterns and sediment provenances in the northern East China Sea(ECS). Sediments of Chinese and Korean rivers, such as Huanghe and Yangtz rivers, Keum and Yeongsan rivers that supply sediments to the northern ECS, were also analysed to figure out their typical REE distribution patterns. The distribution patterns of Chinese and Korean river sediments, which are normalized with upper continental crust (UCC) REE values, appear to be enriched in middle rare earth elements (MREEs) in Chinese river sediments, whereas in light rare earth elements (LREEs) in Korean river sediments. We assign the MREE-enriched convex-type distribution pattern in Chinese river sediments as 'C-type', and the LREE-enriched linearly decreasing pattern in Korean river sediments as 'D-type'. A major constraint of the REE concentration in northern ECS core sediments is interpreted to be LREE-enriched monazite $((Ce,\;La)PO_4)$ that is ubiquitous in and around the study area. Meanwhile, the distribution pattern of northern ECS sediments appears to be between the C-type and the D-type. We suggest that the nothern ECS sediments are the mixture of China and Korea riverine sediments that have been accumulated in paleo-river mouth, paleo-coast, and present-day shelf environment as well. 북동중국해 코아 퇴적물중 희토류 원소(REE) 함량을 분석하여 REE함량의 분포양상을 파악하고 퇴적물 기원지를 추적하였다. 북동중국해로 퇴적물을 공급하는 한국 강(금강, 영산강 등사 중국 강(황하, 양자강 등)에서 유출된 퇴적물 중 REE함량도 분석되어 한국/중국 강에서 유출되는 퇴적물 중 REE함량의 전형적인 분포양상이 구해졌다. 상부지각 중 REE 함량으로 정규화 된 중국 강과 한국 강 퇴적물 중 REE 함량의 분포양상은 각각 중간 희토류 원소(MREE)와 가벼운 희토류원소(LREE)가 부화된 형태로 나타났다. 중국 강 퇴적물에서 나타나는 REE 함량의 분포양상은 "C-type" 즉 MREE가 부화되어 가운데가 불룩한 형태이고, 한국 강 퇴적물에서 나타나는 REE 함량의 분포양상은 "D-type" 즉 LREE가 부화되어 원자번호가 증가함에 따라 직선적으로 감소하는 형태를 보인다. 북동중국해 코아 퇴적물중 REE 함량의 주요 제한인자는 LREE가 부화되어 있고 연구해역 인근 어디에나 분포하는 모나자이트$((Ce,\;La)PO_4)$로 해석된다. 한편, 북동중국해 퇴적물 중 REE함량의 분포양상은 C-type과 D-type의 중간 형태를 보인다. 이러한 중간 형태에 근거할 때, 현재는 대륙붕 환경이지만 과거에는 강 하구였던 북동중국해의 퇴적물은 한국 강과 중국 강에서 유출된 퇴적물의 혼합체로 판단된다.

마산만 표층수에서 물리-화학적 수질요인과 엽록소-a 농도 사이의 관계: 격일 관측 자료

정승원 ( Seung Won Jung ),임동일 ( Dhong Il Lim ),신현호 ( Hyeon Ho Shin ),정도현 ( Do Hyun Jeong ),노연호 ( Youn Ho Roh ) 한국환경생물학회 2011 환경생물 : 환경생물학회지 Vol.29 No.2

In order to investigate water quality factors controlling chlorophyll-a concentrations, the by-daily monitoring was conducted from February to November 2010 in 4 stations of Masan Bay. Seasonal variability in physico-chemical factors was mainly controlled by freshwater loading as a result of precipitation: chemical oxygen demand, suspended solids and nutrient concentrations rapidly increase during the heavy rainy season, whereas they decrease in the dry season. From late winter to mid spring, phosphorus and silica sources relative to Redfield ratio were probably functioned as limiting factor for phytoplankton flourishing in surface waters, but nitrogen concentration during mid-spring to autumn might be responsible for the increase of phytoplankton biomass. The multiple regression analysis revealed that variations in chlorophyll-a concentration may be strongly correlated with changes of water temperature, chemical oxygen demand, dissolved inorganic phosphorus in spring, and salinity, chemical oxygen demand and precipitation in summer. Consequently, in the Masan Bay, a heavy rainfall event is an important factor to determine changes of biotic and abiotic factors, and in addition the dynamics of chlorophyll- a concentration are strongly affected by changes of hydrological factors, especially water temperature, precipitation and nutrients.

서해 함평만에서 조위변화에 따른 영양염 변동

강미란(Mi-Ran Kang),임동일(Dhong-Il Lim),장풍국(Pung-Guk Jang),김기범(Gi-Beum Kim),강영실(Young-Shil Kang) 한국해양환경·에너지학회 2009 한국해양환경·에너지학회지 Vol.12 No.3