U–Pb zircon geochronology is hampered by problems acquiring meaningful geologic ages on zoned grains that retain isotope signatures from multiple growth or thermal events. We present a new method using laser ablation-multicollector-inductively coupled plasma-mass spectrometry to overcome complications asso­ ciated with intricately zoned zircon crystals through in situ sampling of zircon volumes...

A geologic map is a fundamental scientific tool that shows the distribution of geologic material. This study used data gathered at Seven Mile Creek Park to make a geologic map. This data examines the relationships between ravine cutting, terrace development, and base level in a tributary to the Minnesota River, known as Seven Mile Creek. Within the Park there is an extensive network of ravines ...

A geologic map is a fundamental scientific tool that shows the distribution of geologic material. This study used data gathered at Seven Mile Creek Park to make a geologic map. This data examines the relationships between ravine cutting, terrace development, and base level in a tributary to the Minnesota River, known as Seven Mile Creek. Within the Park there is an extensive network of ravines ...

During numerical simulation of geotechnical engineering, due to the complex engineering geological condition, the simplified geologic model is usually adopted. However, the accuracy and reliability of calculating result are directly influenced by characteristic of model. The 3D geologic model can better reflect the actual geological condition. The paper presents a new and practical modeling met...

First posted August 2, 2021 For additional information, contact: Director, Geosciences and Environmental Change Science CenterU.S. Geological SurveyBox 25046, MS-980Denver, CO 80225-0046 This report presents digital geologic, gravity, aeromagnetic maps for the onshore parts of Santa Maria Point Conception 30'x60' quadrangles at a compilation scale 1:100,000. The map depicts distribution bedrock...

This report describes the results of a comprehensive surficial geologic mapping effort undertaken to support the development of a series of relative flood hazard maps of the Ivanpah Valley area, Clark County, Nevada. The study area spans approximately 1030 km2 (398 mi2) and is defined by all of three and part of one internally drained basins between Las Vegas and Primm, Nevada. The proximity of...

Ground motions recorded within sedimentary basins are variable over short distances. One important cause of the variability is that local soil properties are variable at all scales. Regional hazard maps developed for predicting site effects are generally derived from maps of surficial geology; however, recent studies have shown that mapped geologic units do not correlate well with the average s...

Acoustic seabed classification technologies measure acoustic diversity in the seafloor and surficial substrate. This diversity is generally well correlated with both geology and those benthic species which are keyed to geologic and biotic components of the seafloor. Remote acoustic seabed classification has reached a level of maturity and acceptance in the ocean community such that it should be...

Introduction: The Galilean satellites represent a series of bodies that all formed from the same proto-Jovian nebula but are distinctly different in their physical properties, surface geology, and thermal evolution [1-4]. The explanation for many of these disparate characteristics is likely related to the radially varying conditions of the nebula during the earliest period of their formation [5...