중생대 백악기 함평분지의 고퇴적환경과 지질연대를 지화학, 암상 분포, 퇴적암석학 그리고 고식물학 측면에서 재고찰을 시도하였다. 연구 결과는 함평분지가 하성과 호성층으로 구성된 구조적으로 활동적인 분지였음을 시사한다. 이 분지에서는 주변 지형과 관련되어 분명한 환경 변화를 시사하는 산성응회암류, 흑색 셰일/사암상, 적색층, 응회암질 역암을 포함하는 중성응회암류 등 4가지 암상이 인지되었다. 구조적 운동에 수반하여 일어난 화산활동이 이들 퇴적층을 형성시킨 퇴적물을 주로 제공하였을 것이다. 이들 퇴적층들은 인접한 해남분지와 잘 대비된다. 그리고 화산성 기원의 퇴적물들은 유천층군에 해당하는 능주층의 경우와 유사하다. 분지 내에서 흑색 셰일의 광역적인 분포는 혐기성 환경 하에서 퇴적이 이루어졌음을 지시한다. 이들 암층에 있어서의 유기탄소의 함량(0.81%에서 1.75%)은 석유근원 셰일의 평균치 정도로 나타났다. 식물화석은 흑색셰일과 사암에서 산출된다. Platanoid류 잎 화석의 산출은 이들 퇴적층이 Oishi의 피자식물 계열 지층에 해당하며 시대상 Aptian/Albian 또는 보다 신기 지층임을 시사한다.
중생대 백악기 함평분지의 고퇴적환경과 지질연대를 지화학, 암상 분포, 퇴적암석학 그리고 고식물학 측면에서 재고찰을 시도하였다. 연구 결과는 함평분지가 하성과 호성층으로 구성된 구조적으로 활동적인 분지였음을 시사한다. 이 분지에서는 주변 지형과 관련되어 분명한 환경 변화를 시사하는 산성응회암류, 흑색 셰일/사암상, 적색층, 응회암질 역암을 포함하는 중성응회암류 등 4가지 암상이 인지되었다. 구조적 운동에 수반하여 일어난 화산활동이 이들 퇴적층을 형성시킨 퇴적물을 주로 제공하였을 것이다. 이들 퇴적층들은 인접한 해남분지와 잘 대비된다. 그리고 화산성 기원의 퇴적물들은 유천층군에 해당하는 능주층의 경우와 유사하다. 분지 내에서 흑색 셰일의 광역적인 분포는 혐기성 환경 하에서 퇴적이 이루어졌음을 지시한다. 이들 암층에 있어서의 유기탄소의 함량(0.81%에서 1.75%)은 석유근원 셰일의 평균치 정도로 나타났다. 식물화석은 흑색셰일과 사암에서 산출된다. Platanoid류 잎 화석의 산출은 이들 퇴적층이 Oishi의 피자식물 계열 지층에 해당하며 시대상 Aptian/Albian 또는 보다 신기 지층임을 시사한다.
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 predomin...
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.
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.
* AI 자동 식별 결과로 적합하지 않은 문장이 있을 수 있으니, 이용에 유의하시기 바랍니다.
문제 정의
This paper focuses on the Hampyeong Basin (Haenam-Mokpo region; Figure 1), which comprises a sequence of non-marine sediments and volcanics bounded by the north-east to south-west trending Kwangju Fault System. The aim is to document the main facies types in greater detail and to interpret the ancient depositional environment. Stratigraphy and correlation are attempted on the basis of lithology, palaeontology, and geochemistry.
가설 설정
Description: Pinnate leaf fragment (6.3cm long) is incomplete at distal and proximal ends. Rachis is 4mm width at base.
대상 데이터
Compression fossils in the black shale were photographed using cross polar illumination (Rowe, 1999). All specimens are stored in the Department of Oceanography, Chonnam National University, Korea.
The geology, sedimentology, and palaeontology of these smaller basins and their relationships to the Gyeongsang Supergroup are still comparatively poorly understood. This paper focuses on the Hampyeong Basin (Haenam-Mokpo region; Figure 1), which comprises a sequence of non-marine sediments and volcanics bounded by the north-east to south-west trending Kwangju Fault System. The aim is to document the main facies types in greater detail and to interpret the ancient depositional environment.
이론/모형
Chemical analysis of the black shales was undertaken at inter-University Center Natural Science Facilities in the Geology Department of Seoul National University. Fossil plants were described by P, Kenrick (Palaeontology, NHM) using standard palaeobotanical methods. Compression fossils in the black shale were photographed using cross polar illumination (Rowe, 1999).
An attempt to quantify mineral composition of the black shale was undertaken using X ray diffraction analysis (composite of 10 cm thick sample). X-ray diffraction measurements were made by G. Cressy (Mineralogy, NHM) using the rapid phase quantification method (XRD) with a position sensitive detector (PSD) based on the analytical procedure described by Batchelder and Cressey (1998). Chemical analysis of the black shales was undertaken at inter-University Center Natural Science Facilities in the Geology Department of Seoul National University.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.