[Boutique] Geological Internship Report

Part 1: Geological Internship Report

1. Internship overview:

In October 2019, our civil engineering major conducted engineering geology internship. Engineering geology internship is a very important practical part of the whole engineering geology teaching, enabling students to pass the field theory of basic geological phenomena through the study of curriculum theory knowledge. Investigate and practice on the spot, gain perceptual knowledge and consolidate and deepen the curriculum theory, combine theory with practice, and lay a certain foundation for the application of relevant geological data in the design and construction after graduation.

2 Internship purpose

Understand the basic address concepts, understand the basics, and learn the basic skills. Through a brief field address internship, consolidate the content of the "Engineering Geology" that has been studied, and deepen the understanding of the relevant content of the course; in addition, through the internship to cultivate the love of nature, cultivate the sentiment, and improve the interest in the science of address: at the same time fully realize The importance of geological practice to geological science. At the same time, cultivate students' hard work, hard work, discipline, solidarity and other good qualities and enhance the collective concept, master the field operation skills and the ability to write internship reports, sum up the connection between the internship and our major.

3 Internship content:

Changle Crater

The Changle crater, 18 million years ago, is the Cenozoic Tertiary basalt crater. The crater is conical, the stone is reddish-brown, and the momentum is extremely spectacular. Tens of thousands of hexagonal stone columns, from the bottom of the mountain to the top of the mountain, are inserted into the sky.

This crater is a basalt plug filled in a volcanic cylinder. After more than 2 million years of long-term weathering and erosion, it is stripped out of the ground. The columnar joints of the rock bolt develop and radiate, converge upwards and spread downwards, vividly recording the time. The natural landscape of the volcanic eruption shows the magic of nature. According to the research of the Institute of Geology of the Chinese Academy of Sciences, the crater is the volcanic crater of the Tertiary basalt, dating back more than 18 million years. Its discovery has a great reference value for geophysical and seismic science research. One-color red-brown prismatic stone, pointing to the heavens, all of them reveal obvious eruption texture, which indicates that it is caused by volcanic eruptions. Dozens of hills in nearly 100 square kilometers constitute a magnificent ancient volcanic group. .

Shandong Shanwang National Geological Park

Shandong Shanwang National Geological Park is located about 22 kilometers east of Linyi County, Shandong Province, with an area of ​​about 13 square kilometers. The Geopark is located in the Linyi sag in the Luzhong uplift. The park is composed of two sub-small basins, namely the Jiejiahe Basin and the Baojiahe Basin. The periphery is surrounded by basalt hills and the terrain is undulating. Larger. For seasonal rivers. The Geopark features the world-famous Sanwang ancient fossils and volcanic landscapes that reflect its formation.

The park is rich in various geological relics. The first is the 18th century Mesozoic sedimentary rock formation in the Middle Miocene. The sedimentary thickness is about 25 meters. It has a standard layer profile and has become an international Miocene organism. An important basis for building a hierarchy. Because the layer is as thin as paper, it is slightly weathered, that is, the layers are lifted up, just like a book page, which is likened to the "Wan Juan Book" by the ancients. A large number of fossils of paleontology are contained in it. In particular, the location of the layered section of the Shanwang Formation is composed of the early Niushan Formation basalt, the Tertiary Miocene lacustrine sedimentary rocks, the Quaternary loess and the late volcanic rock immersion. Second, various volcanic geological phenomena such as ancient volcanic cones and lava flow characteristics formed by volcanism during the Cenozoic period, such as Huangshan, Lushan, Momashan and Lingshan, are typical ancient craters, so they are also studying the Cenozoic volcanic rocks. The ideal place. In particular, the rubbing Mashan basalt columnar joints, the diameter is nearly 80cm, the scale is grand, and the momentum is spectacular. On the west side of the Lushan Mountain, the volcanic action formed a high platform, which formed a natural landscape after long-term weathering and erosion. People called it "stone building".

The fossils in the Shanwang Formation are formed during the Tertiary Miocene period of 18 million years ago. There are more than 700 species of animal and plant fossils that have been discovered so far, most of which are extinct species. Plant fossils include fungi, diatoms, mosses, ferns, gymnosperms and angiosperms and algae. Animal fossils include insects, fish, amphibians, crawling, birds and mammals. In particular, the discovery of bird fossils such as Shanwang Shandong Bird and Qilutai Mountain Bird has filled the gap in the Miocene period. Shanwang has become one of the rich fossils of bird fossils in China. It is also the world's most famous deer fossils and the best preserved. Fossil origin. The newly discovered rhinoceros fossil with embryos is the only one in the world and caused a sensation in the international academic community. Plant fossils have the most branches and leaves, and flowers, fruits and seeds are also preserved perfectly.

The Shanwang paleontological fossils are mainly preserved in the diatomaceous soil layer of the Miocene Shanwang Formation. The variety and preservation of the species are rare in the world. At present, there are more than a dozen fossils in more than a dozen categories. Animal fossils include insects, fish, spiders, amphibians, crawling, birds, and mammals. Insect fossil veins are clear, preserved intact, and some retain brilliant colors. There are 11 orders, 46 families, 100 genera and 182 species. Shanwang Bird Fossil is the most abundant source of fossils found in China so far. The triangular ancient deer fossils and the oriental ancestral bear fossils are the most intact specimens of the fossils in the Miocene world. Plant fossils include mosses, ferns, gymnosperms, angiosperms, and algae. In addition to 100 species of algae, other plants have 143 species, 98 genera and 46 families. They have an important position in the world in the study of paleoecology, paleoclimate, animal and plant evolution. It has been praised by Chinese and foreign experts as a "comprehensive laboratory" for the study of Miocene.

Shandong Underground Grand Canyon

The high gorge is deep and sorrowful. The waterfall flows into the spring, splashing jade beads. Talented fantasy, gestation in mega-years. Drifting in the dark river, thrilling. Rail slides, aggression. Jiangbei cave, the charm.

Located in the south of Lishui County, 8 km southwest of Longgang Mountain, Shandong Underground Grand Canyon is a unique cave kingdom with a length of 6,100 meters. It is the first longest cave in Jiangbei and one of the most famous caves in China. The cave extends along the direction of 290-320 degrees and is formed by a huge karst fissure running northwest/southeast, which is formed from about 65 million years to 230 million years ago.

Features:

The majestic and magnificent, the canyon is nearly 100 meters deep, the two walls are cut, the width is more than 100 meters, and the narrow place can only accommodate the concrete and the underground and the Three Gorges. There are more than 100 landscapes in the cave, such as the river, Jiuquan, Jiugong, Twelve Waterfalls and Twelve Gorges, which constitute a magnificent picture of the magnificent caves in the cave. It is amazing. The underground underground river is long and tortuous, with abundant water and long flowing seasons. The underground river waterfall is very spectacular, and it is rare in the caves in northern China.

The 1000-meter drifting project developed by the use of the dark river water potential was certified as the “longest cave drifting in China” project by the Shanghai World Records. The design of the drifting channel fully reflects the deep and unpredictable inside the cave, the ups and downs, the wave surge, and the stagnation. The original wilderness of the underground river rafting, the thrilling and exciting interpretation.

4 Internship summary:

In just one day, the field internship is coming to an end, but we have learned a lot from it and can understand the knowledge we have learned flexibly during the internship. Increase our new understanding of the course of engineering geology. Various geographical features were actually observed. This internship has deepened our understanding of geology, and has deepened the understanding of the significance of learning geology, consolidating the learning outcomes, and realizing the path of “learning to use”. Knowledge has sublimated from perceptual recognition to rational understanding. From abstraction to concreteness, I have learned a lot of things that are not in the book and understand the importance of engineering geology to actual engineering construction. I am deeply grateful to the teachers for their serious guidance. In the internship, I learned a certain method and details for observing the geological features. For example, an out-of-town internship should have a certain understanding of the object of the investigation, reasonably arrange the inspection route and the contents of the investigation, pay attention to the research methods, and the details of some investigations, fully recognize the necessity and hardship of the geological and geomorphological investigation, and stimulate our own exploration of geography. And interest in typical geological features around the country. At the same time, understand the importance of working with group members. These will play a positive role in our future study and even work.

Part 2: Geological Internship Report

First, the purpose of the internship:

This internship is a field understanding of geology courses. Its purpose is to provide a comprehensive and general understanding of the main content and characteristics of geological research through short-term field practice, to consolidate and master the basics of geology. The content and method have the ability to analyze and solve the address problem under the simple conditions appearing in the actual project, and lay a solid foundation for future work practice. The main purpose is three:

Understand various geological phenomena and understand the basic stratigraphic sequence of the North China platform.

Understand the various geological effects of internal and external forces.

Initially master the general field geological skills, observe, record and describe the use of the compass instrument from the field.

In addition, through the internship, the students fully realized the importance of geological practice to the geological discipline and its important role in the national economic construction, thus gradually establishing the ideological style of hard work and the scientific and realistic spirit of courage to explore.

Second, internship time: May 16, 2019 to May 20, 2019

Third, internship location: Shimenzhai Geological Practice Base in Qinhuangdao

Fourth, the composition of personnel:

V. Internship route: Liangjiashan - Chaoshuiyu - Goat Village - Shimenzhai - Shangzhuang - Dashihe - Xiaoyan Shuiya Village - Wuzhuang - Huachang

Sixth, internship introduction:

1. Location and traffic of the internship area

This time, our internship area is located in the beautiful coastal city of Qinhuangdao City and Funing County and Qinglong County, which is the only non-freezing port in the north of China. It is from Qinhuangdao, Beidaihe Seashore in the south, Huayuan, Yiyuankou in the north, Shanhaiguan in the east, Zhang Cliff. Zi, west to Wajiashan and other places, the total area is about 120Km2. The Shimenzhai Northern Geological Practice Base of Qinhuangdao City is located at 28KM in the north of Qinhuangdao City. The natural geography of the area is located in the eastern section of the Yanshan Mountains, bordering on the North China Plain and the Bohai Bay in the south. The administrative division is under the jurisdiction of Shimenzhai Township, Funing County, Qinhuangdao City, Hebei Province.

The traffic in the internship area is very convenient. The Beijing-Shenzhen Railway runs through the southern part of the internship area, and there is a local railway Qin-Qing line, which can lead to the mountainous area. The highway is centered on Qinhuangdao City and is well-connected. Passengers can pass through Qinglong, Chengde, Pingquan, Qixian, Qian'an, Funing, Xinglong, Changli and Lulong in the province, and can reach Liaoning Yuzhong and Jianchang outside the province. Zuo left, Lingyuan Chaoyang and Tianjin. There is currently no passenger transport on the sea, but the new oil port and coal port cargo can be transported from Qinhuangdao Port to all parts of the coastal area of ​​China and the rest of the world.

2. Terrain terrain

The internship area is adjacent to Bohai Sea in the south, Yanshan in the north, Yuzhong in the east and Changli in the east. It is located in the eastern section of the Yanshan Mountains, surrounded by mountains in the north, east and west. The mountains are close to the north-south trend and the terrain is gradually decreasing from north to south. It belongs to the mid-bottom mountainous area and low mountainous area in northeastern Yunnan. The highest point is Shihu Mountain, with an elevation of 926 meters and the lowest point in the southern coastal area, with an elevation of only 0.8-5 meters.

3. Climate of the internship area

The internship area is a temperate continental monsoon climate with an annual average temperature of 10.1 °C, the average temperature in January is -5 °C, the average temperature in July is 24. 5 °C, the annual average precipitation is 769 mm, mostly concentrated in July-August. , the annual precipitation is about 70%. The frost-free period is 179 days throughout the year. The internship area is affected by the ocean, the climate is relatively humid and mild, and the beachside area is cool and pleasant in summer, and it is a summer resort.

4. Hydrological situation in the internship area:

The main rivers in the internship area include Dashihe, Tanghe and Beidaihe. Except for the Dashi River originating from Niuxin Mountain in Qinglong County, the rest are from the northern mountainous area of ​​Funing County. Each river is a unique watershed with short rivers and rapid flow. The change is large, the average water depth is about 0.5 meters, and the water depth can reach 2-3 meters during flood season.

Yanshan Saihu is located at the 6KM mountain pass in the northwest of Shanhaiguan City. At the foot of Yanshan Mountain, it is an artificial lake. It was built in 1994 and has a water storage capacity of 70 million cubic meters.

5. The economic situation of the internship area.

The industrial area of ​​the internship area is very developed. It is centered on Qinhuangdao, with shipbuilding, machinery, building materials, coal, textiles, food processing, etc. The Shanhaiguan Bridge Factory and Qinhuangdao Yaohua Glass Field enjoy a good reputation throughout the country. The agriculture in the internship area is mainly the arid crops in the north, mainly rice, corn, wheat, sorghum, millet and sweet potato. The mountains are rich in fruits and herbs. The fishery, shrimps and crabs in the internship area are one of the main aquatic bases in northern China.

6. Internship to terrain introduction

The exposed area of ​​this internship area belongs to the North China platform type. In addition to the general loss of the Upper Ordovician to Lower Carboniferous, Lower Middle Triassic, Cretaceous, and Tertiary, as far as the North China strata are concerned, the strata are more exposed and rich in fossils, and each unit stratum The division marks are clear and the stratigraphic features are representative. All the exposed strata in the whole area include the Qingbaikou group of the Proterozoic, the Cambrian of the Lower Paleozoic, the Lower Ordovician, the Middle Carboniferous to the Permian of the Upper Paleozoic, and the Upper Triassic of the Mesozoic The Quaternary system of the Jurassic and the New World.

Seven, internship content:

1. Strata:

The exposed area of ​​this internship area belongs to the North China platform type. In addition to the general loss of the Upper Ordovician to Lower Carboniferous, Lower Middle Triassic, Cretaceous, and Tertiary, as far as the North China strata are concerned, the strata are more exposed and rich in fossils, and each unit stratum The division marks are clear and the stratigraphic features are representative. All the exposed strata in the whole area include the Qingbaikou group of the Proterozoic, the Cambrian of the Lower Paleozoic, the Lower Ordovician, the Middle Carboniferous to the Permian of the Upper Paleozoic, and the Upper Triassic of the Mesozoic The Quaternary system of the Jurassic and the New World.

Yuanbaijie Qingbaikou Group

Longshan Formation

It is distributed in Zhangyazi to the east, and in the south of Jiguanshan. It consists of two sedimentary rhythms. It is not integrated on the Huanggangyan in the middle of the Yellow Emperor. It is mainly variegated shale such as fuchsia, yellow-green, gray-black and egg white, and the bottom is sandstone. It is a typical coastal phase deposit, which is in sedimentary relationship with the underlying granite. 91 meters thick.

Jingeryi Group

It is mainly distributed in the eastern part of the region. The best profile is exposed in the Lizhuang North Ditch, and it is also exposed in the east of Huangtuying Village. The lithology is from coarse to fine, and the clastic rock-clay rock-carbonate rock constitutes a complete rhythm and has the characteristics of transgressive sedimentation. It has an integrated contact relationship with the Longshan Formation. The demarcation mark is a medium-fine-grained iron quartz sandstone with a yellow-brown or rust-colored bottom, which contains a large amount of glauconite, and the middle-fine-grained feldspar quartz net sandstone at the bottom has a large sea-forming storm wave mark. The formation of this group belongs to the coastal phase to shallow marine facies deposition. 38m thick.

Cambrian

Fujunshan Formation

Shantou group

Due to the intrusion and structural damage of the rock mass, the group is exposed to sporadic, and the northern and western parts of the eastern part are exposed, which can be used as a standard section. The upper and lower limits of this group are obvious, and the boundary with the Maozhuang group is marked by the bright red mudstone at the top. The lithology is characterized by bright red mudstone and shale, and the shale contains rock salt pseudocrystals with dolomitic limestone. No reliable fossil basis was found. Parallel unconformity contact with the underlying Fujunshan group; integrated contact with the Shangfu Maozhuang group. 71m thick.

Maozhuang Group

Xuzhuang Group

The distribution is relatively wide, the eastern part of the west is well exposed, and the fossils are very rich. The upper and lower boundaries of the formation are clear and can be used as standard sections. The yellow-green mica-bearing siltstone with lithology is shallow sea, with dark purple siltstone, fine sandstone and a small amount of smectite limestone lens or lentils. Contains trilobite fossils. The boundary between the underlying Maozhuang Formation is marked by the interbedded layer of yellow-green siltstone and dark purple siltstone. 101m thick.

Zhang Xia Group

It is covered and destroyed less. It is one of the most widely distributed strata in the Cambrian strata. It is distributed around almost the basin. It is best exposed on the ridge east of the 288 highland of Xinzhuang North. Good standard profile. The lower part is a braided limestone with yellow-green shale; the upper part is dominated by braided limestone, with algae limestone and muddy limestone. Trilobite fossils are the most abundant. This group is in integrated contact with the underlying strata. Thickness 130m.

Lushan Group

This group is similar to the distribution of the Zhangxia group in the area. It is better to have a section on the 288 high ground, which can be a standard section. The lower part and the upper part are mainly purple boulder limestone and purple siltstone; in the middle part, the gray limestone and Zhangxia group have obvious boundaries, and the lithology of the contact part is very different. Fossils are very rich and can be harvested on almost every floor. The main trilobite fossils are: bat worm unspecified species, P. variabilis. 102m thick.

Changshan Formation

The well-exposed profile is in the 288 highland of Xinzhuang North, which is a standard section. The lithology is purple diabase, siltstone and shale interbed, with algae and bio-ash. Trilobite fossils mainly include: undetermined species of Artemisia sinensis, undetermined species of Changshan worm, and unspecified species of worms. The boundary between the two and the underlying strata is clear. This group has a small thickness in the area, only about 18m.

Fengshan Formation

The distribution of this group is the same as that of the Lushan Formation and the Changshan Formation, and the high-rise Xinzhuang North 288 highland can be used as a standard section. The main lithology is yellow-gray marl brittle-gravel marl. Yellow-green calcareous shale and thin layered argillaceous banded limestone. The shale composition is increased and it is easy to be weathered, and weathering often forms a yellow soil. Fossil-rich trilobite fossils have obvious vertical zoning. The gravel forms a small mass, and the group is in contact with the underlying Changshan Formation. The boundary is marked by the blue-grey gravel marl at the bottom. 92m thick.

Ordovician

Yeli Group

It is distributed in the east and west of the region, mainly in the eastern region. It is better to show off in Chaoshui to Xinzhuang. The lower part is gray microcrystalline pure limestone with a small amount of boulder limestone and wormhole limestone; the upper part is gray gravel limestone with yellow-green shale. The fossils produced include trilobites, pen stones, and brachiopods. In contact with the underlying Fengshan Formation, the stratified mark is based on gray boulder limestone, which is very thin, less than 0.5m thick, and is pure limestone. Thickness is 125m.

Liangjiashan Formation

Located in Shijiazhai Liangjia Mountain. It is a shallow sea sediment. The main lithology is medium-thick layered leopard limestone with a small amount of boulder limestone and calcareous shale. Contains fossils such as cephalopods, gastropods, and unidentified species of the snail. In contact with the underlying smelting group, the boundary is marked by the medium-thick layered leopard skin limestone at the bottom of Liangjia Mountain. After weathering, it is muddy strip-like and contains shale tuberculosis. The layer thickness is 118m.

Majiagou Formation

This component is consistent with the Liangjiashan Formation, and is well developed in Liangjia Mountain and Beishan Mountain in the north. It is a shallow marine sediment, which is deeper in water environment. The lithology of this group is dominated by dolomite and dolomitic limestone, and the bottom has micro-layered, breccia-containing, yellow-white dolomitic limestone containing meteorite nodules. Fossils are: cephalopods and gastropods. The integration with the underlying Liangjiashan group is very obvious. Dolomite has a "knife mark". The layer thickness is 101m.

Carboniferous

Benxi Group

The Benxi Group of the Carboniferous is widely distributed in the east and west of the district. The best development and excavation is the development of the 191 highland and Xiaowangzhuang area of ​​Banbidian. The Xiaowangzhuang section can be used as the standard section of this area. There are 2-3 complete sedimentary rhythms from land to sea. The lithology characteristics of this group are consistent with those in North China, and it is a set of interactions between sea and land. The terrestrial siltstone contains plant fossils: scale wood, Koda, and reed. The lower part is iron sandstone, limonite and clay rock, parallel unconformity and above the Majiagou Formation; the upper part is fine sandstone, siltstone and shale, with 3-5 layers of marl lens. The stratum thickness of the Ximen-Wajiashan section of Shimenzhai is 70.7m.

Taiyuan Group

It is well developed in the area of ​​Banbi and Xiaowangshan. The lithology of this group is relatively stable. The main feature of iron-black sandstone containing iron-bearing nodules is that a small number of coal lines and limestone lens bodies are composed of two rhythms, which are interactive sediments of sea and land. Containing plant fossils: veins, scales, animal fossils: long-lined shells, ancient Nile. It has integrated contact with Benxi Formation and has obvious boundary. The bottom of this group is blue-gray iron medium-fine feldspar lithic sandstone with small spherical weathering. The Wajiashan section is 48m thick.

Permian

Shanxi Group

It is mainly distributed in the eastern Heishan kiln to Caoshan area, and it is also exposed in the west. There are two rhythms, the first rhythm contains coal seams, and the top of the second rhythm contains bauxite. This group is an important coal-bearing stratum in the area and belongs to the offshore marsh sediment. The main lithology is gray, gray-black medium-fine feldspar lithic sandstone, siltstone carbonaceous shale and clay rock. Containing plant fossils: unrecognised aloe, with Koda, slender leaves. It has an integrated contact with the underlying Taiyuan group. The thickness varies greatly, from about 35m to 60m.

Lower stone box group

It is distributed in the area from Heishan Kiln to Shiling, with scattered distribution in the west. It consists of three rhythms. It belongs to lake sediments. The main lithology is gray medium-grained feldspar lithic sandstone. Containing plant fossils: multi-pulse with ferns, Shanxi with ferns, with Kodak. The layer thickness is 115m.

Upper stone box group

It is mainly exposed in the Heishan Kiln and Huanxiling to the west side of the Dashi River. The well-developed profile is Huanxi Ridge, which can be used as a standard profile. The lithology features the gray-white medium-thick layered pebbly coarse-grained feldspar sandstone of the facies, with a small amount of purple fine-grained sandstone and siltstone. This group did not obtain fossil data. It has an integrated contact relationship with the underlying stone box group. The layer thickness is 72m.

Shi Qianfeng Group

The original named place was Shiqianfeng, 25km west of Taiyuan City, Shanxi Province. This group is the top group of the Permian. The better exposed profile is from Huanxiling to Wakashan, which can be used as a standard profile. The main lithology is a set of purple facies in the facies, including siltstone, mudstone, a small amount of conglomerate, coarse to medium-fine net sandstone and mixed sandstone. Containing plant fossils: Taiyuan with ferns, pointed leaves, and Korean feathers. The integrated contact relationship with the underlying stone box group can be distinguished from the color. Thicker than 150m.

2. Rock:

Magma rock

1 granite

It is exposed in the vicinity of Zhangzhangzi Village in the east, or under the Jiguan Mountain in the southwest, and the sediment is not integrated under the quartz sandstone of Maling Formation. The rock is fleshy or grayish white, but the distribution of the rock mass is very uneven and the structural structure changes greatly. The granites from the west flower plant to the hot springs are belonging to the late Mesozoic intrusive granites according to the contact relationship and isotopic age. The rock mass is very large and is fleshy red. It consists of feldspar, plagioclase, quartz and a small amount of biotite. It has a medium-fine grain phenotypic structure, so it is called medium-grain porphyritic granite.

2 granite porphyry

Exposed to the southeast of Shiling, it is a patchy structure of fine-grained matrix, which is produced by rock wall and invades in the Late Cambrian to Middle Ordovician strata. Potassium feldspar and quartz phenocryst are often etched by the matrix. In the west of Chaoshui Village, there is a granite porphyry wall with a width of more than 5m.

3 gray green rock

The Liangjia Mountain quarry is relatively concentrated. The rock is dark green, fine-grained, with a typical girdle structure, and some pyroxene has been chlorite and citrate.

4 diorite

It is distributed in the northwest of Chaoshuiyu Village, in the east of Casserole, and other places. It is rock-walled and has a cryptic plaque structure. The phenocryst is mainly plagioclase, sometimes contains amphibole, and some matrix contains a small amount of quartz. Visible spherical structure and streamline structure.

5 Andesan

It is distributed in the Middle Jurassic strata of the Liujiang syncline nucleus. It is quite rich in types, including Xuanwu Andesite, Huishi Andesite, Angling Anshan Rock, Xiehui Andesite, Diagonal Changanshan Rock, Ruan'anshan Rock and Ying'an Mountain Rock. Most of them have a hidden plaque structure. The color is mainly gray-green, a few are dark purple-red, generally in a block-like structure, and a few have a stomatal structure and an almond structure.

Sedimentary rock

1 Quartz sandstone containing glauconite

The Longshan Formation of Qingbaikou Group in Zhang Cliff has a medium-grained quartz sandstone with a surface that is weathered into a yellow-brown interior, which is grayish white, with shallow marine deposits, including glauconite and a small amount of mica.

2 pure limestone

Rock with calcite as the main component. Gray-black, brittle, hard, and the knife can be swiped. The pure limestone of the Liangjiashan Formation observed in Shimenzhai contains gravel, which is the cryptocrystalline limestone or microcrystalline mudstone debris generated in the basin.

3 leopard skin limestone

It is mainly distributed in the Liangjiashan Formation. The piebald is composed of dolomite and is light yellow or brownish yellow, which is distinct from the surrounding gray or dark gray gray matter components, especially those with mottling wormholes. On the weathered surface of the rock, wormholes and plaques are often symbiotic, which is the symbol of leopard skin limestone.

4 micro-layered dolomitic limestone

It is distributed in the strata of the Junshan Formation of the Lower Cambrian, and the Zhangyazi area is well developed. The mottling is limited to a certain layer of strata, and there is no cutting relationship with the stratum level, indicating that the metasomatism is completed in the diagenetic stage. The structure inside the layer is uniform and formed in a shallow sea deep water environment.

Metamorphic rock

Fault breccia is also known as crushed breccia and tectonic breccia. It is a breccia-like rock formed by the fracture of rock due to tectonic action. The breccia is of different sizes and angular. The lithology is the same as the rock on both sides of the fault, and is cemented by the fine debris of the same composition and the substance in the aqueous solution of the epigenetic effect. .

3. Geological structure:

Construction location of the work area

The area is located in the eastern section of the Yanshan subsidence belt, the southeastern margin of the Shanhaiguan uplift, and the transition zone between the modern Yanshan uplift and the Bohai depression and the elbow-shaped part of the Yanshan Mountains turning from east to west. The stress is concentrated, so new and old The structures are relatively developed. According to the Tianjin Institute of Geology and Mineral Resources of the Ministry of Geology and Mineral Resources, the fault structure is developed in this area, with NNE-trending faults being the most developed, followed by NW-trending faults, NE--NEE-trending faults and EW-trending faults. In addition, it is still developing in the north of Shanhaiguan. There is a ring fracture.

Structural overview

The exposed strata in this area belong to the North China platform type, while the Jurassic system belongs to the Pacific volcanic activity belt. In addition to the general loss of the Middle Ordovician to Lower Carboniferous, Triassic, Cretaceous and Tertiary, other stratigraphic development It is good, and the exposure is more comprehensive. The divisions of the local units are marked with obvious signs. The fossils are rich and representative. The strata exposed in the whole area include the Qingyuankou of the Upper Proterozoic, the Lower Cambrian, and the Lower Ordovician. In the Upper Paleozoic, the Carboniferous, the Permian, the Mesozoic Jurassic and the Cenozoic Quaternary.

The Longshan Formation of the Qingbaikou Formation in the Upper Paleozoic was deposited on the Suizhong granite by angle unconformity, indicating that the North China Platform experienced a severe Luliang movement, ending the early Proterozoic geosyncline development stage and entering a relatively stable geological development stage.

During the Cenozoic period, there was a clear ascending movement. The whole area was denuded. At the end of the third period, due to the hot climate, red soil formed and then continued to rise. However, the southern coastal area sank and suffered transgression. Therefore, there are terraces in the mountain valleys, which are generally southward, that is, inclined toward the ocean. By the end of the Quaternary, the sea had a certain retreat, so there were gravel embankments on the coast of Shanhaiguan to Qinhuangdao, and there was a sea erosion platform.

Main fault structure description

Tidal water fault

In the tidal zone, the fault strikes N20°E and tends to the southeast. The upper plate is the argillaceous banded limestone of the Fengshan Formation; the lower plate is the thick layer of limestone of the Yeli Formation. The fault plane appears as a soothing wave in both the oblique direction and the strike direction. The mirror surface, vertical scratches, step and the extrusion lens in the fracture zone are obvious. The cliff is a plate of translational fault, and the other disk is basically invisible due to weathering and erosion. The fault is the limestone of the Yeli Formation, and there are obvious horizontal and vertical scratches and mirrors. The fault first translates to produce a normal fault. Its occurrence is basically consistent with the appearance of Liangjia Mountain. In the east of Chaoshui Village, the east of the cliff is part of another section of the fault. It contains obvious fault breccia and siltstone and there are obvious horizontal and vertical scratches, but the occurrence and the occurrence of Liangjia Mountain are inconsistent, so it may be Another set. There is also a small fault in the Majiagou Formation in Liangjia Mountain with obvious scratches.

Jiguanshan

1 See the flesh-red sorghum granite along the way. See a large exposed rock section as a typical sedimentary interlaced bedding. It belongs to the top of the Sinian original paleo-border. The main component is quartz sandstone, with horizontal bedding on the upper and lower sides, and staggered bedding in the middle. There is a black textured magnetite.

See the muddy interlayer, reflecting the changes in the sedimentary environment in the coastal area, affecting the biological growth environment, not reflecting climate change, geological conditions, and can not be used as the basis for the era division.

2Typical bottom conglomerate: the lower part is the bottom conglomerate, which has strong anti-weathering ability and is continental sedimentary, with gravel-quartz sandstone in the middle, quartz coarse sandstone in the upper part, quartz fine sandstone in the upper part, and marine sediment in the upper part. Form a complete mud rhythm.

Cause: Due to weathering and river handling, the final sedimentation. From bottom to top, the rock is coarse to fine, and the bottom conglomerate is originally cemented together. The cement is cerium oxide and a small amount of iron. Later, the entire porphyrite has a normal fault. , resulting in a height difference from the upper bottom conglomerate.

3 normal fault: When a fault occurs, the relatively rising lower plate undergoes weathering and erosion, so that the rock on the exposed surface is weathered and rounded, resulting in a small height difference between the two faults, and the fault layering is good. Due to the short formation time, the layering If the formation time is long, it is an unconformity surface. Tendency: 243 degree inclination: 48 degrees.

4 Wave marks: iron quartz sandstone with glauconite, good symmetry, wide wave marks and equal wavelengths, reflecting the coastal sedimentary environment. It is inferred that the sea bottom fluctuates greatly, the water depth is shallow, and the wave marks extend direction and The coastline is parallel.

In the valleys where Jiguanshan and the large platform are asked, due to the influence of several normal faults, the quartz sandstones of the Xiamaling Formation on both sides of the Qingbaikou Formation are relatively rising, and the middle quartz sandstones are descending. The fault plane is close to the north-south direction, and the dip angle is large. The fault plane on the east side of the valley is tilted westward, and the fault on the west side of the valley faces eastward, forming a mantle structure, and the valley itself is located at the center of the mantle structure.

4. Geological effects:

Weathering: refers to the mechanical disintegration and chemical change process of rock on the surface or near the surface due to temperature changes, the action of water and aqueous solution, the atmosphere and biology. Weathering generally falls into three categories: physical weathering, chemical weathering, and biological weathering.

Physical weathering: Under the change of temperature, the surface layer and the interior are unevenly heated, resulting in expansion and contraction. The long-term effect causes the rock to collapse and break.

Chemical weathering: The mineral components in rocks often undergo chemical decomposition under the action of oxygen, carbon dioxide and water to produce new substances. Some of these substances are dissolved by water, with the loss of water, and some insoluble substances remain in place.

Biological weathering: the growth of plant roots, the activity of cave animals, and the decomposition of humic acid formed by the decomposition of plant bodies can change the state and composition of rocks.

The role of rivers: the geological processes of rivers are divided into erosion, transport and sedimentation. River sedimentation mainly occurs when rivers enter the sea, enter the lake and branch into the main stream, or in the middle and lower reaches of the river, and the convex bank of the meander. But most of it is deposited in the oceans and lakes. River sediments account for only a small portion of the transported material, and are mostly temporary deposits that are easily eroded and transported again.

Erosion: The erosion of rivers includes both mechanical and chemical erosion. On the one hand, river erosion washes down the riverbed, which is called undercutting. On the other hand, the river's destruction of the valley slopes on both sides of the river bed by its own power and the sand and gravel of the river is called lateral erosion, while the chemical erosion of the river is only obvious in the soluble rock area, and it is not as common as mechanical erosion.

Carrying effect: During the flow of river water, the river transports the substances that are eroded by the river itself and collapsed and washed down on the valley slope. Most of them are mechanical debris, and a small part are various compounds dissolved in water. The former is called mechanical handling, and the latter is called chemical handling. The amount of river mechanical transport is related to the flow and flow rate of the river, and is also related to the natural geologic conditions in the basin.

Sedimentation: When the slope of the river bed is reduced, or the moving material is increased, and the flow velocity is slowed down, the river's handling capacity is reduced, and the debris in the river water is gradually deposited to form a layered alluvial deposit. For sedimentation.

Magma effect: Magmatic rock is a rock formed by the coagulation of magma, accounting for about 65 of the total volume of the earth's crust. Magma is a high-temperature viscous strontium melt fluid that is naturally formed in the deep crust or in the upper mantle and is rich in volatile components. It is the precursor of various magmatic and magmatic deposits. The whole process of magma occurrence, migration, accumulation, change and condensed diagenesis is called magmatism. There are two main ways of magma:

Magmatic intrusion activities → intrusive rocks. Magmatic rocks mainly have two kinds of output conditions: intrusion and ejector. A rock that invades a certain depth of the earth's crust and slowly cools it, called an intrusive rock.

Volcanic activity or squirting activity → spurting rock in the process of magma rising from the upper mantle or deep crust along a certain channel to the crust to form intrusive rock or ejected to the surface to form eruptive rock, due to changes in physical and chemical conditions such as temperature and pressure, The properties, chemical composition and mineral composition of magma are constantly changing. Therefore, the magmatic rocks formed in nature are diverse and ever-changing, such as basic rocks, neutral rocks, acidic rocks, and alkaline rocks. Rocks such as carbonates also fully explain the complexity of magma composition

Eight, internship summary:

The five-day field internship soon ended, and we learned a lot from it. Increase our understanding of the course of engineering geology and understand the importance of engineering geology to actual engineering construction. This internship saw a lot of geological structures and rocks described in the textbooks, learned how to use the compass, practiced using the topographic map to determine the position using the resection method, and practiced the geological map to judge the age of the local rock formation. , the birthplace, etc., profoundly feel that only the knowledge on the textbook is not enough, but also through practice can really turn the knowledge into its own use. This internship really gained a lot, thank the two teachers for their hard work.

Part 3: Geological Internship Report

The structural position of Lianhua Mountain is located in the deep fault zone since the Caledonian movement. It was formed during the orogenic period of the Yanshan Movement in the Mesozoic, and is a typical fold mountain system. The Lianhuashan Mountain Range enters the Hua'an area of ​​Fujian Province in Fengshun, Meixian and Dapu in the northeast; to the southwest: to the Haifeng and Huidong Baoan counties in Daya Bay, Shenzhen Bay, such as the South China Sea, and again from the Wanshan Islands and Gaolan archipelago. Guangdong has a length of about 500km, a width of 20 to 40km, and a partial area of ​​60km. The deep fault is a strong crushing zone with more than 120 faults. It is divided into east and west faults. There are 13 trunk faults in the southeast and 14 trunk faults in the west. This kind of dynamic thermal metamorphism is strong, and it can find minerals such as lead, zinc, copper, tungsten and tin. It is an important guiding rock structure. There are many fracture-type intermittent eruptions in the medium-acid magma. Within the deep fault, there are more than 100 rock masses. It is a metallogenic belt of endogenous metal deposits.

Stratigraphy: The Jurassic system is collectively referred to as the Gaojiping Group. This group is a complex set of continental volcanic rock series composed of neutral, medium-acidic, acidic volcanic lava and corresponding volcanic clastic rocks and sedimentary rock interlayers.

In the morning of 10 or so, several classes of our civil engineering majors took the school bus to the Lianhua Mountain. The road to the mountain was steep, but the scenery along the way was good. The birds and flowers all the way, could not help but want to get off quickly and enjoy it. Finally arrived at the top of the mountain, after getting off the bus, we followed the teacher, listening to the teacher's explanation, while enjoying the beautiful scenery. The first thing that caught your eye was the Wanghai Guanyin, which was grand and magnificent. The Wanghai Guanyin gold statue is more than 40 meters high. This Guanyin is like the Xia lion sea and the lustrous Nantian. It is said to be the world's best foil gold and bronze statue. At this time, the sunset is just west, and the Guanyin is like a Buddha. On the right side of Wanghai Guanyin is the Guanyin Pavilion. It is an antique single building. It has three floors and is wide open, with a veranda. It is built according to the big wooden style of the Qing Dynasty. It is majestic and solemn, magnificent and antique. On the third floor, there is the plaque of "Lotus Temple". In front of the main hall, there is a large-scale incense case. The fragrant customers are sincerely burning incense and praying for blessing.

Going down the stone steps, you will arrive at the Lion Rock. It is a stone standing proudly, like a male lion. It is estimated to be named here. It is said to be one of the symbols of Lianhua Mountain. This stone was eroded by ancient sea tides. It seems that the water level is still high here thousands of years ago. The lithology of the stone is the brown-red sandstone of sedimentary rocks. The layered structure is obvious and it is very easy to be weathered.

Next is the Eagle Eagle Trail and Feiying Cliff. The Eagle Eagle Trail is an artificially excavated tunnel. The tunnel cave is relatively large and penetrates the entire rock formation. The rock lithology is the brown-red sandstone of sedimentary rocks, and the bedding structure is obvious.

We followed the teacher all the way. Opposite the Lion Rock is the Guanyin Rock. It is a rock that protrudes outward from the upper part and is recessed inward in the lower part. It has the words “Guanyin Rock” on it, and the lithology is also the brown red in the sedimentary rock. Sandstone, which is dedicated to a statue of Guanyin, many devout men and women worship in the top, as well as marriage, although I do not believe this, but in the face of the compassionate Guanyin Bodhisattva, I even want to ask for a sign, but Finally did not go, but followed the teacher. Next is the Eight Immortals Rock. The Eight Immortals Rock is actually a group of rocks. The plates are different in shape, but they are patchwork. The lithology is brown-red sandstone. The rock bedding structure is obvious. There are plant cover on the upper part. Horizontal joints, vertical joints, and inclined joints appear on the rocks. Wave joints, some joints run through the entire rock group. It is obvious that the rock is subjected to relatively large tensile stress and biological weathering.

In the process of watching, because there were too many people, we walked away, did not keep up with our team, but with the teacher of another class, we came to the bath Xianchi, listening to the teacher, this is a Precipitation and surface water are small pools formed in the lower reaches of the rock formation. The pool is artificially treated in an elliptical shape. On the side of the pool, it is a statue carved with white stones. It is a bit like the fairy goddess in Tianlong Ba Bu. The statue, the fairy sister's hairpin on the head, is preparing to bathe, and the bath fairy pond is named after it. Under the guidance of the teacher, we found that the sandy rocks around the pool have been blown by the winds of the sun and rain forests for a long time. The wild matter grows, and the weathering degree is strong. Some rock surfaces have been broken and cut, and the rock fragments in the lower part of the rock are weathered into powder and piled up. It is earthy and its engineering geological properties are extremely poor. This weathered rock should not be used as the foundation bearing layer of construction engineering.

We followed the teacher and went to the Bilian pool. Unfortunately, there is no lotus in the pool. Only the fish are swimming around. It is free and comfortable. It is also very happy. The Bilian pool pavilion and the corridors, the small bridge and the mountains and rocks On the high rock wall, there is a poem "How many floors are the first, the lotus swallows are smashed. In front of the lions, the waves are not in the water." On the rock behind the lotus pond, a statue of Guanyin carved in white jade is erected.

Going forward, you will go to Yanziyan. The Yanziyan is composed of two high-rise rocks. The two rocks are integrated into one. After the ancient quarry, the lower part is cut open, and two rocks rise above the surface. There is also a sightseeing pavilion on the top of Yanziyan. It looks very dangerous. There is a sloping joint on the rock, but these two fast rocks have not gone down for thousands of years, which is really amazing. Connected to the Yanziyan is the ancient quarry. This quarry has a history of more than 2,000 years. The cliffs and cliffs of the ancient quarry are strangely carved. It seems to be excavated by the gods. Known for its unique scenery and scientific value, the Shijing wonders are the miracle of the “Artificial Danxia”. The horizontal quarry structure of the quarry in the ancient quarry is obvious, and the inclined joints are particularly prominent. The width of the quarry is long and the length is long. The bottom of the quarry forms a depression due to the low terrain, and the surface water is accumulated for many years to form a water lake.

The above is my graduation internship report. The one-day internship ended like this. I originally planned to use the internship as a watersport, but I found that there is a harvest. This is a process of combining theory with practice. In this process, we must understand and apply the knowledge we have learned flexibly. In order to strengthen our understanding of this course, and in the process of internship, I learned a lot of things that could not be learned in books. The ancients said that reading thousands of books is not as good as traveling thousands of miles. It seems that this is the truth. Also thank the teacher for his careful guidance. Through this field internship, I also understand the truth: to have a certain understanding of the objects to be inspected, and to prepare in advance, you will not be overwhelmed when you arrive.