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The road landscape computer aided technology in China's engineering survey in the development and application, and in road mapping, building survey has an important role, its development and promotion of China's building construction of far-reaching significance. This paper describes the current road landscape, the practical application of computer aided technology for computer aided technology, the principle of road landscape is analyzed, and puts forward the ground of the stationary road landscape of computer-aided technology in actual production process, the application of technology is analyzed, put forward the road landscape trend of computer aided technology application in the engineering survey, in order to offer reader reference.

Two‐ and three‐dimensional mechanical models simulating the seismic cycle along thrust faults are devoted to the active front of the Northern Apennines buried under the Plio‐Pleistocene sediments of the eastern Po Plain. The models aim at understanding two peculiar characters of the stress field in the region: (1) analyses of borehole breakouts and other well data, integrated with seismological information and field evidence, show along‐depth variations (from extensional to strike slip to compressional for increasing depth) of the stress style along the active Mirandola anticline and (2) seismic and borehole breakout data suggest strong lateral rotations of the stress axes along the frontal and lateral ramp portions of the Mirandola thrust fault. Modeling results allowed us to understand that the mechanical decoupling along faults strongly affects the stress distribution in their vicinity, under the form of strong rotations of the principal stress axes. As a consequence the slip (either fast or slow) along active blind thrust faults could drive to local stress fields very different from that associated with regional tectonics. This could explain, together with other processes (such as differential compaction), the along‐depth variation of the stress field observed in the Mirandola region and the strong lateral rotations of the principal stress axes observed along the lateral ramp of the Mirandola thrust fault. Finally, the seismic activity along one of the thrust fault ramps along the Apennines front should not interfere with the state of stress along adjacent ramps.

In South Australia’s Eyre Peninsula, groundwater provides 85% of the region’s reticulated water supply. Fresh groundwater resides within shallow karstic limestone aquifers recharged by incident rainfall. Water levels are very responsive to short-term climate variability and are at risk of sustained decline due to long-term drying trends and the further rainfall declines indicated by projections of future climate, thereby increasing risk to water security and groundwater-dependent ecosystems. In 2009, a new adaptive resource management approach was enabled through legislative reform that better addresses climate variability, particularly where aquifer robustness is low. This allows the volume of water available for licensed allocations to be varied annually depending on the current condition of the aquifer resources. A three-tiered trigger level policy varies the rate at which water allocations are limited in proportion to monitored changes in groundwater storage. The three trigger thresholds are specified for each discrete groundwater resource, based on levels of risk. We now have more than five years of observations and practice of this approach to learn of its efficacy and consequences for water users, the water resources, and the environment. It has proved to be an effective way to deal with the uncertainties in how and when climate may change and how water management principles can effectively respond. Our case study provides an example of the importance of legislative reform to enable adaptive water resource management to effectively tackle the challenges of water planning in a drying climate.

The Charity Shoal structure is a circular, ∼1.2‐km‐diameter, bedrock‐rimmed shoal in eastern Lake Ontario with a ∼20‐m‐deep central basin. The structure has been proposed as a possible Middle Ordovician impact crater or volcanic intrusion. We conducted marine seismic and magnetic surveys (9‐km2) and 3‐D geophysical modeling to better resolve the Charity Shoal subsurface geology and possible origins. Three models were evaluated: (a) a buried (>450 m) impact structure in Mesoproterozoic basement, (b) a maar‐diatreme, (c) a cylindrical, zoned volcanic plug. Seismic profiles and multi‐beam bathymetry revealed >30 m of Quaternary sediments overlying Middle Ordovician (Trenton Group) carbonate bedrock and complex, 3‐dimensional folding and faulting of the structure rim. Magnetic surveys recorded an annular magnetic high (>600 nT) over the structure rim and a central magnetic low (∼500–600 nT) coincident with a ∼−1.7 mGal Bouguer gravity anomaly. The continuity of Trenton Group strata in seismic profiles rules out a previously proposed Mesozoic maar‐diatreme intruded into Paleozoic strata. The zoned volcanic plug model reproduced the annular magnetic anomaly but was incompatible with Bouguer gravity profiles. The magnetic anomaly was best reproduced by a simple impact structure seated in Mesoproterozoic basement at 450–500 m depth with a rim‐to‐rim diameter of ∼1.2 km and rim height of ∼10–20 m. A 100‐m wide and 50‐m‐deep channel in the Mesoproterozoic basement may record fluvial dissection of the southwestern rim. A buried (>450 m), simple impact crater is most compatible with all available geophysical data at Charity Shoal. Plain Language Summary The Charity Shoal structure is 1.2‐km‐diameter, circular bedrock‐rimmed shoal on the lakebed of eastern Lake Ontario. The crater‐like structure has been investigated in three previous studies (Holcombe et al., 2001, https://doi.org/10.1016/s0380‐1330(01)70664‐8; Holcombe et al., 2013, https://doi.org/10.1007/s00367‐013‐0322‐6; Suttak, 2013, http://hdl.handle.net/11375/13532) and proposed as a possible karst sinkhole, glacial erosional feature, volcanic intrusion or meteorite impact crater. We conducted geophysical surveys and 3‐D modeling at Charity Shoal to evaluate several possible geological origins. An impact crater model was most compatible with the available geophysical data, which indicate a deeply buried “crater‐form” structure in the Precambrian basement at a depth of >450 m. Our geophysical results rule out a proposed impact crater within the Middle Ordovician sedimentary rocks, as that model cannot reproduce the large gravity and magnetic anomalies recorded at Charity Shoal. Key Points Charity Shoal is a 1.2 km diameter, crater‐like bedrock shoal in northeastern Lake Ontario previously proposed as a Middle Ordovician impact structure or maar‐diatreme 3‐D subsurface modeling of magnetic, seismic, and gravity data indicates a deep‐seated (>450 m) crater‐form structure in Mesoproterozoic basement Geophysical modeling supports a probable origin as a Mesoproterozoic‐early Paleozoic simple impact structure

This chapter looks at organizations or research groups who are in the process of setting up a 3‐D modeling project or are reviewing the effectiveness of an existing 3‐D modeling program. A generic geologic modeling workflow clarifies the major computational steps that occur and major iterations that can take place within a single modeling project. Six operational considerations can be used to help ensure success of geologic modeling projects. They include: identifying and prioritizing user requirements; defining mapping objectives; and evaluating the likely geologic complexity within the model domain. They also include: determining availability of, and management options for, existing data; estimating how much new data will be collected; and evaluating availability and expertise of personnel. Most modeling software has evolved to accommodate multiple modeling methods and a wide range of geologic scenarios. The chapter summarizes the experiences of four organizations–one university and three geological survey organizations–that provide examples of workflow solutions to issues.

The use of 3‐D models to support historical preservation and archeological investigations is a relatively recent development, one that has increasing relevance in 3‐D modeling of urban areas where anthropogenic processes have significantly modified the urban subsurface. This chapter contains three case studies, the first two of which discuss recent examples of the application of 3‐D models to historical preservation and to the assessment of the vulnerability and characteristics of anthropogenic deposits in urban areas. The second case study describes the development of a 3‐D digital geological model which combines information from borehole logs with archeological evidence for the central area of the city of Newcastle upon Tyne. The third case study provides a more detailed discussion of the challenges associated with 3‐D mapping and modeling of Artificially Modified Ground.

This chapter highlights the concepts, methods, and tools that used to create 3‐D stacked‐surface geological framework models and demonstrates effective modeling strategies and applications using stacked surfaces. The stacked‐surface approach has been widely used to conceptualize geology. The stacked‐surface approach to 3‐D modeling utilizes regular 2‐D grids to represent individual surfaces. Many geographic information systems software products support a broad range of interpolation algorithms with variable parameter‐control options and allow the user to specify combinations of these basic interpolation methods. Three‐dimensional visualization is very useful for ensuring model consistency and accuracy. Geophysical surveys, synthetic boreholes, and supplemental elevation data are principal sources of synthetic data used in stacked‐surface modeling. The chapter describes selected examples where stacked‐surface modeling was effective at building geologic frameworks directly associated with aquifer delineation. Stacked‐surface modeling will continue to be applied as an independent modeling strategy, and as a component of more complex and varied 3‐D modeling software applications and workflows.

This chapter contains sections titled: Operative Lines and Modelling Software Philosophies of Design after Delanda Attribute Data and the Virtual Line States of Line Conclusion: Confronting Abstraction

This chapter contains sections titled: Introduction Steelwork detailing Constructing a 3‐D model of a steel structure Object orientation CNC/rapid prototyping Future developments