Wellbore properties measurement and determination

1. A system for measuring one or more physical properties of a wellbore, the system comprising:

a tool comprising:

a main body configured to be disposed within a tubular string within a wellbore at least partially filled by a wellbore fluid, wherein tool is configured such that a location of the tool within the tubular string is changeable between a surface location and a downhole location;

one or more sensors disposed on or in the main body and configured to measure one or more downhole parameters from which, at least in part, the one or more physical properties of the wellbore can be determined;

a memory module disposed within the main body and configured to receive and store downhole parameter measurements from the one or more sensors; and

a flapper disposed on the main body and configured (a) to, in response to the position of the tool changing from the surface location to the downhole location, pivot radially with respect to a longitudinal axis of the main body from a closed position in which the flapper is aligned with the main body to an open position in which the flapper is away from the main body, and (b) to, in response to the position of the tool changing from the downhole location to the surface location, pivot radially with respect to the longitudinal axis of the main body from the open position to the closed position; and

a control module disposed at or proximate the surface location and configured to receive data from the memory module after the tool has traveled from the downhole location to the surface location.

2. The system of claim 1 , wherein the control module is configured to be wirelessly connected to the memory module.

3. The system of claim 1 , wherein the tool is configured such that the position of the tool can be changed from the surface location to the downhole location by propulsion of the tool by a flow of wellbore fluid pumped into the tubular string.

4. The system of claim 1 , wherein the tool is configured such that the position of the tool can be changed from the downhole location to the surface location by propulsion of the tool by a buoyant force exerted by the wellbore fluid.

5. The system of claim 1 , wherein the tool is less dense than the wellbore fluid.

6. The system of claim 1 , wherein the tool further comprises a piston disposed within the main body and mechanically coupled to the flapper, and wherein the tool is configured such that the flapper pivots in response to a translation of the piston due to a change in hydrostatic pressure of the wellbore fluid acting on the tool.

7. The system of claim 1 , wherein the wellbore fluid comprises a drilling fluid and the tubular string comprises a drill string.

8. The system of claim 1 , wherein the one or more physical properties comprises an azimuth of the wellbore and wherein the one or more downhole parameters comprises an azimuthal orientation of the main body.

9. The system of claim 1 , wherein the one or more physical properties comprises an inclination of the wellbore and wherein the one or more downhole parameters comprises an inclination of the main body.

10. The system of claim 1 , wherein the one or more physical properties comprises a depth of the wellbore at the location of the tool and wherein the one or more downhole parameters comprises a hydrostatic pressure of the wellbore fluid acting on the tool.

11. The system of claim 1 , wherein the tool further comprises a battery disposed within the main body and configured to provide electrical power to the memory module.

12. The system of claim 1 , wherein the tool is spherocylindrical in shape and is configured such that the major axis of the tool is parallel to an axis of the tubular string in which the tool is disposed.

13. A tool for determining one or more physical properties of a wellbore, comprising:

a main body configured to be disposed within a tubular string within the wellbore, wherein the wellbore is at least partially filled by a wellbore fluid and the tool is configured such that a location of the tool within the tubular string is changeable between a surface location and a downhole location;

one or more sensors disposed on or in the main body and configured to measure one or more downhole parameters from which, at least in part, the one or more physical properties of the wellbore can be determined; and

a flapper disposed on the main body and configured (a) to, in response to the position of the tool changing from the surface location to the downhole location, pivot radially with respect to a longitudinal axis of the main body from a closed position in which the flapper is aligned with the main body to an open position in which the flapper is away from the main body, and (b) to, in response to the position of the tool changing from the downhole location to the surface location, pivot radially with respect to the longitudinal axis of the main body from the open position to the closed position.

14. The tool of claim 13 , wherein the tool is configured such that the position of the tool can be changed from the surface location to the downhole location by propulsion of the tool by a flow of wellbore fluid pumped into the tubular string.

15. The tool of claim 13 , wherein the tool is configured such that the position of the tool can be changed from the downhole location to the surface location by propulsion of the tool by a buoyant force exerted by the wellbore fluid.

16. The tool of claim 13 , wherein the tool further comprises a piston disposed within the main body and mechanically coupled to the flapper, and wherein the tool is configured such that the flapper pivots in response to a translation of the piston due to a change in hydrostatic pressure of the wellbore fluid acting on the tool.

17. The tool of claim 13 , wherein the wellbore fluid comprises a drilling fluid and the tubular string comprises a drill string.

18. The tool of claim 13 , wherein the one or more physical properties comprises an azimuth of the wellbore and wherein the one or more downhole parameters comprises an azimuthal orientation of the main body.

19. The tool of claim 13 , wherein the one or more physical properties comprises an inclination of the wellbore and wherein the one or more downhole parameters comprises an inclination of the main body.

20. A method for determining a physical property of a wellbore at least partially filled with a wellbore fluid, the method comprising:

disposing a tool within a tubular string within the wellbore at a surface location, the tool comprising:

a main body;

one or more sensors disposed on or in the main body and configured to measure one or more downhole parameters from which, at least in part, the one or more physical properties of the wellbore can be determined;

a memory module disposed within the main body and configured to receive and store downhole parameter measurements from the one or more sensors; and

a flapper disposed on the main body;

flowing the wellbore fluid through the tubular string in a downhole direction, thereby propelling the tool from the surface location to the downhole location, such that the flapper, in response to an increase in hydrostatic pressure of the wellbore fluid acting on the tool as the tool travels from the surface location to the downhole location, pivots radially with respect to a longitudinal axis of the main body from a closed position in which the flapper is aligned with the main body to an open position in which the flapper is away from the main body;

reducing a flow rate of the wellbore fluid, such that a buoyant force exerted by the wellbore fluid propels the tool from the downhole location to the surface location and such that the flapper, in response to a decrease in hydrostatic pressure of the wellbore fluid as the tool travels from the downhole location to the surface location, pivots from the open position to the closed position; and

receiving, from the memory module after the tool has traveled from the downhole location to the surface location, downhole parameter measurements from the one or more sensors.