概括
研究人员在南美洲深边缘发现了最古老的沉积物. 这种浅水砂岩可以追溯到罗纪晚期,为早期大西洋裂和海底形成提供了洞察力.
科学领域:
- 地质地质地质地质地质地
- 古生物学的古生物学
- 海洋学 海洋学 海洋学
背景情况:
- 南美洲的深边缘代表了理解早期大西洋演变的前沿.
- 来自该地区的沉积物记录对于重建古地理和构造历史至关重要.
研究的目的:
- 确定和描述在南美洲深边缘发现的最古老的沉积沉积物.
- 为了确定新发现的深海沉积物的沉积环境和年龄.
主要方法:
- 沉积物核心从4400米深的德梅拉拉高原恢复.
- 对沉积物组成的分析 (石灰质砂岩,颗粒大小).
- 使用palynomorphs和软体动物镜进行生物层状图分析.
主要成果:
- 从南美洲深边缘采集到目前为止最古老的沉积物样本的回收.
- 浅水,粗粒度,石灰质砂岩的识别.
- 沉积物可以追溯到罗纪晚期 (或可能是白纪早期) 时期.
结论:
- 回收的砂岩表明,在罗纪晚期,浅水沉积在一个大陆海域.
- 这一发现为大西洋裂变的初始阶段和随后新形成的海洋盆地的沉没提供了证据.
更多相关视频
10:39Multimodal Optical Microscopy Methods Reveal Polyp Tissue Morphology and Structure in Caribbean Reef Building Corals
Published on: September 5, 2014
07:30Using Archival Japanese Paper and Thermoplastic Resins to Prepare Fossils for Storage, Display, Transport, and Radiography
Published on: November 14, 2025
相关概念视频
Quarrying of Stone
Quarrying is the process of extracting stone from a quarry, where specialized techniques are employed to remove large blocks of stone safely and efficiently. This process can involve controlled explosions or more precision-oriented methods such as cutting and drilling.
One common method involves using a diamond belt saw to cut large blocks from the quarry face. These blocks can be about 50 feet long and 12 feet high. After the initial vertical cut, drilling is performed at the base of the block.
One common method involves using a diamond belt saw to cut large blocks from the quarry face. These blocks can be about 50 feet long and 12 feet high. After the initial vertical cut, drilling is performed at the base of the block.
The Fossil Record
The fossil record documents only a small fraction of all organisms that have ever inhabited Earth. Fossilization is a rare process, and most organisms never become fossils. Moreover, the fossil record only exhibits fossils that have been discovered. Nevertheless, sedimentary rock fossils of long-lived, abundant, hard-bodied organisms dominate the fossil record. These fossils offer valuable information, such as an organism's physical form, behavior, and age. Studying the fossil record helps...
Types of Building Stone
Building stones, essential materials for construction, are extracted from natural rock deposits and processed into specific forms and dimensions suitable for various building applications. These stones are broadly classified into three types based on their geological formation: igneous, sedimentary, and metamorphic.
Igneous rocks are formed from the solidification of magma or lava. An example is granite, known for its durability and resistance to weathering, making it ideal for parts of...
Igneous rocks are formed from the solidification of magma or lava. An example is granite, known for its durability and resistance to weathering, making it ideal for parts of...
Brick Masonry
Brick masonry uses bricks as the building blocks and involves building walls from individual bricks laid in mortar. The basic building block of brick masonry is the wythe, a vertical layer of bricks with a thickness of one brick. Within a wythe, bricks can be laid in various courses or patterns, with the most common being the stretcher course, where bricks are laid with their long edge horizontal and face parallel to the wall.
For thicker walls, multiple wythes are bonded together using...
For thicker walls, multiple wythes are bonded together using...
Effect of Sea Water on Concrete
Concrete exposed to seawater can undergo degradation like the dissolution of ettringite and gypsum, increasing the material's porosity and decreasing its strength. In contrast, the crystallization of salts within the concrete's pores can cause expansion, particularly above the waterline where evaporation occurs. Nonetheless, this expansion only happens when seawater, enabled by the concrete's permeability, manages to infiltrate the structure.
Concrete in areas between tide marks, which undergo...
Concrete in areas between tide marks, which undergo...
Portland Cement
Portland cement is the essential binding ingredient in concrete, made from finely ground materials including lime, iron, silica, and alumina. Lime is derived primarily from limestone, marble, marl, seashells, and clays, which also supply iron and alumina, while silica is sourced from sand, chalk, and bauxite. Contemporary manufacturing of Portland cement is a significant source of carbon dioxide emissions, prompting research into reducing its content in concrete through alternative...
