Maryland strike and dip data
7,038 structural measurements in Maryland, digitized from 14 published geologic maps across 4 sources. Every row carries its azimuth, inclination, measurement type, location confidence and the citation of the map it came from.
- 7,038Measurements
- 14Published maps
- 2,992Other
- 4Sources
What kinds of measurement
The Atlas separates planar structures, recorded as a strike and dip, from linear ones, recorded as a trend and plunge. This is what Maryland holds:
| Measurement type | Geometry | Measurements | Share |
|---|---|---|---|
| Other | Planar — strike and dip | 2,992 | 43% |
| Bedding | Planar — strike and dip | 2,344 | 33% |
| Cleavage | Planar — strike and dip | 1,367 | 19% |
| Foliation | Planar — strike and dip | 182 | 3% |
| Lineation (mineral, stretching) | Linear — trend and plunge | 56 | <1% |
| Fold hinge / axis | Linear — trend and plunge | 54 | <1% |
| Joint | Planar — strike and dip | 37 | <1% |
| Vein / dike | Planar — strike and dip | 6 | <1% |
Where the data comes from
Each source is a survey, agency or program whose published mapping was harvested and reconciled into one schema. Rows are published only where the source's terms permit redistribution.
| Source | Measurements | Share |
|---|---|---|
| NGMDB legacy quads | 3,182 | 45% |
| USGS NGMDB GeMS | 2,400 | 34% |
| Maryland Geol. Survey | 1,450 | 21% |
| USGS data releases · MRDS | 6 | <1% |
Most-measured published maps
The individual quadrangles and data releases contributing the most measurements in Maryland. The full
citation for every map behind a selection ships in the sources.csv of any export.
Most-measured map units
Where a source recorded the geologic unit a measurement was taken on, the Atlas keeps it. These are the units carrying the most measurements in Maryland.
| Map unit | Age | Lithology | Measurements |
|---|---|---|---|
| Catoctin Formation - massive metabasalt Zcm | Late Proterozoic | Meta-mafic rock | 246 |
| Catoctin Formation - massive metabasalt Zcm | Late Proterozoic | Metaigneous rock | 239 |
| Weverton Formation - Buzzard Knob Member Cwb | Cambrian | Quartzite | 214 |
| Zcm | — | — | 206 |
| Basement Gneiss Complex - leucocratic gneiss Ygl | Middle Proterozoic | Medium and high-grade regional metamorphic rock, of unspecified origin | 196 |
| Conococheague Formation - Elbrook Formation Ce | Cambrian | Limestone | 172 |
| Chilhowee Group - Harpers Formation Ch | Cambrian | Slate and phyllite, of sedimentary-rock origin | 144 |
| Tomstown Formation - Dargan Member Ctd | Cambrian | Dolomite | 115 |
| Dh | — | — | 114 |
| Tomstown Formation - Bolivar Heights Member Ctbh | Cambrian | Dolomite | 111 |
| Df | — | — | 110 |
| Pc | — | — | 97 |
Other states
- California98,381
- Washington77,518
- Colorado52,726
- Montana49,196
- Alaska48,959
- Idaho45,068
- Virginia43,190
- Oregon40,787
- South Dakota37,339
- Vermont36,132
- Pennsylvania30,313
- Arizona30,240
- Maine26,897
- New Hampshire26,863
- North Carolina18,766
- Wyoming18,214
- Nevada15,033
- Connecticut11,575
- Utah9,668
- Wisconsin8,802
- Massachusetts8,162
- New Jersey7,797
- New York7,202
- Oklahoma6,682
- All states →