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Atacama Desert Landscape Evolution in Response to Short-Duration Triggering Events: Insights Across Scales of Time and Space- [electronic resource]
Atacama Desert Landscape Evolution in Response to Short-Duration Triggering Events: Insights Across Scales of Time and Space- [electronic resource]
상세정보
- 자료유형
- 학위논문파일 국외
- 최종처리일시
- 20240214101522
- ISBN
- 9798380318471
- DDC
- 551
- 서명/저자
- Atacama Desert Landscape Evolution in Response to Short-Duration Triggering Events: Insights Across Scales of Time and Space - [electronic resource]
- 발행사항
- [S.l.]: : Cornell University., 2023
- 발행사항
- Ann Arbor : : ProQuest Dissertations & Theses,, 2023
- 형태사항
- 1 online resource(302 p.)
- 주기사항
- Source: Dissertations Abstracts International, Volume: 85-03, Section: B.
- 주기사항
- Advisor: Jordan, Teresa.
- 학위논문주기
- Thesis (Ph.D.)--Cornell University, 2023.
- 사용제한주기
- This item must not be sold to any third party vendors.
- 초록/해제
- 요약The landscape evolution at varying temporal and spatial scales in the Atacama remains an important issue that has not been fully addressed holistically. Previous studies have tended to focus on the effects of short-lived phenomena or the climatic and tectonic evolution of the area. This dissertation presents a multi-scale approach to investigating landscape change in the Atacama, with a focus on extreme rainfall events and their impact on different geological units, as well as the study of weathering controls in small scale objects. These objectives were achieved by integrating remote sensing and field observations which allowed us to enhance our understanding of the entire landscape.The first part of this study presents a simple method to identify areas of extreme surface change using Change Vector Analysis (CVA) and Principal Component Analysis (PCA) applied to Landsat 8 OLI imagery from two rain events in 2015 and 2019. The results were corroborated by comparing with previous studies and field observations, demonstrating that CVA and PCA can be used to identify various types of change, including salt development, soil moisture, and mass transfer, even up to 60 kilometers away from the loci of the rain.In the second part of this study, Synthetic Aperture Radar (SAR) images were used to study the effects of the 2019 rain event. Time series of InSAR coherence expressed as similarity matrices and time series of Sentinel 1-A backscattering were employed to reveal different types and rates of change in a wide range of geological materials. These included salt flats located in the hyperarid core of the Atacama that displayed transient and delayed change, and salt flats located in the high Andes that showed immediate and progressive change. Results also included gypsic soils displaying transient temporal change and mudflow deposition. All results were placed in the context of long-term changes that have been identified or estimated previously to provide a link between short-term and long-term evolutionary paths. In general, the study area needs more frequent rain events or infrequent but more intense rainfalls to generate the landscape to its current display.Finally, the study of a field of weathering boulders that decay to debris cones with small scale stratigraphic records in the hyperarid core of the Atacama Desert could lead to a rich Holocene and Pleistocene climatic or earthquake history for the area. These boulders result from rockfall from the Chuculay fault scarp in the Coastal Cordillera and weather in a semi-closed system where most of the material detached from the boulders is now in their surrounding detritus cones. The relative weathering stages within a collection of boulders are not necessarily a valid metric for their relative ages, meaning that boulders that have lost 50% (stage 3 out of 5) of their original volume can be older than boulders that are now a pile of sediments (stage 5 out of 5). The factors that control the weathering rates are still undetermined for the Atacama. Using a wide range of tools, including Structure from Motion (SfM), Raman spectroscopy, and field observations, this part of the study reveals that there are many complexities that need to be solved in order to extract environmental information from the boulder/detritus cone systems. These include weathering rates that are highly controlled by the fracture frequency, content of ferromagnesian minerals, and boulder size, in addition to the development of sulfate levels in the detritus cones that are the result of environmental phenomena that are present only under specific conditions related to water influx and the location of the boulders.
- 일반주제명
- Geology.
- 일반주제명
- Remote sensing.
- 일반주제명
- Geomorphology.
- 키워드
- Atacama Desert
- 키워드
- Boulders
- 키워드
- Surface change
- 키워드
- Weathering
- 기타저자
- Cornell University Geological Sciences
- 기본자료저록
- Dissertations Abstracts International. 85-03B.
- 기본자료저록
- Dissertation Abstract International
- 전자적 위치 및 접속
- 로그인 후 원문을 볼 수 있습니다.
MARC
008240612s2023 us |||||||||||||||c||eng d■001000016934045
■00520240214101522
■006m o d
■007cr#unu||||||||
■020 ▼a9798380318471
■035 ▼a(MiAaPQ)AAI30570187
■040 ▼aMiAaPQ▼cMiAaPQ
■0820 ▼a551
■1001 ▼aOlivares Manque, Lester Andres.▼0(orcid)0000-0001-6525-2258
■24510▼aAtacama Desert Landscape Evolution in Response to Short-Duration Triggering Events: Insights Across Scales of Time and Space▼h[electronic resource]
■260 ▼a[S.l.]:▼bCornell University. ▼c2023
■260 1▼aAnn Arbor :▼bProQuest Dissertations & Theses, ▼c2023
■300 ▼a1 online resource(302 p.)
■500 ▼aSource: Dissertations Abstracts International, Volume: 85-03, Section: B.
■500 ▼aAdvisor: Jordan, Teresa.
■5021 ▼aThesis (Ph.D.)--Cornell University, 2023.
■506 ▼aThis item must not be sold to any third party vendors.
■520 ▼aThe landscape evolution at varying temporal and spatial scales in the Atacama remains an important issue that has not been fully addressed holistically. Previous studies have tended to focus on the effects of short-lived phenomena or the climatic and tectonic evolution of the area. This dissertation presents a multi-scale approach to investigating landscape change in the Atacama, with a focus on extreme rainfall events and their impact on different geological units, as well as the study of weathering controls in small scale objects. These objectives were achieved by integrating remote sensing and field observations which allowed us to enhance our understanding of the entire landscape.The first part of this study presents a simple method to identify areas of extreme surface change using Change Vector Analysis (CVA) and Principal Component Analysis (PCA) applied to Landsat 8 OLI imagery from two rain events in 2015 and 2019. The results were corroborated by comparing with previous studies and field observations, demonstrating that CVA and PCA can be used to identify various types of change, including salt development, soil moisture, and mass transfer, even up to 60 kilometers away from the loci of the rain.In the second part of this study, Synthetic Aperture Radar (SAR) images were used to study the effects of the 2019 rain event. Time series of InSAR coherence expressed as similarity matrices and time series of Sentinel 1-A backscattering were employed to reveal different types and rates of change in a wide range of geological materials. These included salt flats located in the hyperarid core of the Atacama that displayed transient and delayed change, and salt flats located in the high Andes that showed immediate and progressive change. Results also included gypsic soils displaying transient temporal change and mudflow deposition. All results were placed in the context of long-term changes that have been identified or estimated previously to provide a link between short-term and long-term evolutionary paths. In general, the study area needs more frequent rain events or infrequent but more intense rainfalls to generate the landscape to its current display.Finally, the study of a field of weathering boulders that decay to debris cones with small scale stratigraphic records in the hyperarid core of the Atacama Desert could lead to a rich Holocene and Pleistocene climatic or earthquake history for the area. These boulders result from rockfall from the Chuculay fault scarp in the Coastal Cordillera and weather in a semi-closed system where most of the material detached from the boulders is now in their surrounding detritus cones. The relative weathering stages within a collection of boulders are not necessarily a valid metric for their relative ages, meaning that boulders that have lost 50% (stage 3 out of 5) of their original volume can be older than boulders that are now a pile of sediments (stage 5 out of 5). The factors that control the weathering rates are still undetermined for the Atacama. Using a wide range of tools, including Structure from Motion (SfM), Raman spectroscopy, and field observations, this part of the study reveals that there are many complexities that need to be solved in order to extract environmental information from the boulder/detritus cone systems. These include weathering rates that are highly controlled by the fracture frequency, content of ferromagnesian minerals, and boulder size, in addition to the development of sulfate levels in the detritus cones that are the result of environmental phenomena that are present only under specific conditions related to water influx and the location of the boulders.
■590 ▼aSchool code: 0058.
■650 4▼aGeology.
■650 4▼aRemote sensing.
■650 4▼aGeomorphology.
■653 ▼aAtacama Desert
■653 ▼aBoulders
■653 ▼aLandscape evolution
■653 ▼aSurface change
■653 ▼aWeathering
■690 ▼a0372
■690 ▼a0799
■690 ▼a0484
■71020▼aCornell University▼bGeological Sciences.
■7730 ▼tDissertations Abstracts International▼g85-03B.
■773 ▼tDissertation Abstract International
■790 ▼a0058
■791 ▼aPh.D.
■792 ▼a2023
■793 ▼aEnglish
■85640▼uhttp://www.riss.kr/pdu/ddodLink.do?id=T16934045▼nKERIS▼z이 자료의 원문은 한국교육학술정보원에서 제공합니다.
■980 ▼a202402▼f2024
